SECTION I - CLASS DEFINITION
(A) This is the generic class for amplifiers as limited by the
definition of amplifiers as it appears in the Glossary below.
(B) Included are amplifiers having all types of active elements
(or amplifying devices, the term used in this class) as for example
vacuum tubes, gas tubes, semiconductors, magnetic type saturable
reactors, masers, etc.., as set forth in the specific subclasses
in the schedule for the class. Specific types of vacuum tube amplifier devices
included are, traveling wave type tubes, secondary emission type
tubes, electron beam tubes, magnetrons, etc.
(C) Included are amplifier systems having plural amplifier
channels, cascade amplifiers, push-pull amplifiers and other amplifiers
having plural amplifier devices. Also included are amplifiers with
plural signal sources or plural loads, as for example sum or difference
amplifiers which have plural sources.
(D) Amplifiers including the means coupling the signal source
to the amplifier or coupling the amplifier to the load or between
cascaded stages are also included herein. Such coupling means include
those of the distributed parameter type, resonant tuned circuits,
filters, coupling designed to pass a broad band, D.C. coupled circuits,
potentiometer means for volume control, equalizers, circuits for
volume control, etc.
(E) Amplifiers combined with tone control means are also included
herein as indicated in D above for the type included in the amplifier
coupling means, also included herein are those tone control amplifiers
relying on signal feedback means to effect the tone control.
(F) Amplifiers combined with amplitude (volume) control means
whether by manual control, by control of an electrode D.C. bias,
as in gain control, or by controlling a variable impedance means
for the signal transmission path of the amplifier are also included
herein.
(G) Amplifiers combined with power supply means for such amplifier
are also included herein, as well as means to control the voltage
or current of such means.
(H) Amplifiers combined with structural features of the amplifier
or the amplifier circuit elements including structure of the amplifier
device, capacitors, transformers, etc.
(I) Amplifiers having signal feedback means.
SECTION II - LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
A. TWO-TERMINAL NEGATIVE RESISTANCE NETWORKS
Such networks containing an active element (amplifying device)
are not classified in this class, but classified elsewhere. (See
References to Other Classes, below.)
B. LIMITERS
Passive networks which limit the signal amplitude voltage
or current are classified elsewhere.Miscellaneous limiting
circuits with active device elements are classified elsewhere.
(See References to Other Classes, below.)
C. MISCELLANEOUS ELECTRONIC TUBE CIRCUITS
Circuits including electron tubes (other than the limiters discussed
above) in which the signal output is not a substantial replica of
the input signal, are classified residually elsewhere. Examples
of such tube circuits are wave conversion circuits, miscellaneous
pulse generating systems, and electronic tube gating circuits.
(See References to Other Classes, below.)
D. SATURABLE REACTOR CIRCUITS (MAGNETIC AMPLIFIERS)
Such circuits which control voltage or current and are not
classifiable herein (as for example, where the A.C. power supply
current is not removed from the signal output by filtering or other
means) are classified elsewhere. Saturable reactor circuits for
wave shaping, switching, pulse production, etc., analogous to similar electronic
tube circuits are classified elsewhere with nonlinear reactor systems,
and computers using magnetic amplifiers are also classified elsewhere.
(See References to Other Classes, below.)
E. NONLINEAR REACTOR CIRCUITS:
Where a nonlinear capacitor serves as the active element or
amplifying device in a circuit which switches, shapes a wave, or
produces pulses and is not provided for elsewhere classification
is in Class 307. So called amplifier circuits including a nonlinear
capacitor as the amplifying device, which have an A.C. source where
the claims do not provide a filter to remove the A.C. source from the
output or where a demodulator is claimed and no filter or other
means to remove the A.C. power supply from the signal output circuit
is disclosed, are excluded from this class. (See References to
Other Classes, below.)
F. MISCELLANEOUS TRANSISTOR CIRCUITS:
Transistor circuits which are not amplifiers or not combined
with an art device or in a system specifically provided for in some
class, are classified elsewhere. Such art as miscellaneous transistor
wave shapers, gating circuits, limiters, and pulse producers are
classified therein. (See References to Other Classes, below.)
G. AMPLIFIER COMBINED WITH SPECIFIC SOURCE OF SIGNAL ENERGY:
This class does not provide for combinations of amplifiers
with a specific source of electric signal, such as a microphonewhich limits the system to use with a
particular art even though the source is claimed by name only. Similarly,
where the source is claimed by characteristics specific to the art
device as for example, "a source of speech signals" classification
is not in this class. However, classification is in this class where
the source is claimed by its electrical characteristics not specific
to the source device, as for example, "a high impedance source
of electrical signal". Where the specific source, or details
thereof are claimed, classification is with the art device so identified.
(See References to Other Classes, below.)
Generator or Oscillator Claimed By Name Only
The terms generator or oscillator in claims, where they appear
as sources of signal energy without further qualification except
by their electrical characteristics such as impedance, reactance,
etc., are treated as generalized sources of signal energy, and classification
is with amplifiers except where specific details of the generator or
oscillator are claimed; in such cases classification is with the
type of generator claimed or with oscillators. (See References
to Other Classes, below.)
H. AMPLIFIERS COMBINED WITH SPECIFIC LOAD:
Where the load is claimed, broadly, or by name only as a specific
electrical art device, as for example, as a loudspeaker, classification
is not in this class but with the load art device claimed. Where
characteristics of the load device are claimed, which are peculiar
to the disclosed electrical art device or to a specific type of
electrical art device, classification is with the load art device established
in the claim. Subject matter wherein general electrical characteristics
of the load are claimed, as for example, "a load having
a variable impedance," is classified in this or indented
subclasses. (See References to Other Classes, below)
I. OSCILLATOR AS A LOAD FOR AN AMPLIFIER
Subject matter wherein an amplifier is combined with an oscillator
as load for the amplifier is classified with amplifiers when the
oscillator is claimed by name only; where specific details of the
oscillator are claimed, classification is elsewhere. (See References
to Other Classes, below.)
J. REPEATERS:
Devices known in the art as repeaters which are in effect two-way
amplifiers are not classified in this class but are classified elsewhere.
(See References to Other Classes, below.)
K. AMPLIFIERS COMBINED WITH LONG LINE TRANSMISSION MEANS
OR DISTRIBUTED PARAMETER ELEMENTS, AND AMPLIFIERS COMBINED WITH
WAVE FILTERS, EQUALIZERS OR ATTENUATORS:
Such subject matter is classified herein even though the amplifier
is claimed by name only, if some detail of the co-operation of the
amplifier with the passive network (coupling) is claimed. (See
References to Other Classes, below.)
L. COMPANDERS INCLUDING AMPLIFIERS:
Systems including means to compress a signal wave, an electrically
long transmission line and means to expand the signal wave are not
classified herein even when they include details of an amplifier.
Companders are classified elsewhere. Amplifiers with compressor
or expander means alone not involving a complete compander system
are classified herein. Such subcombinations
involving connection or maintenance of a predetermined condition
of the transmission line are classified elsewhere.Where
such connection is of an amplifier condition classification is herein.
(See References to Other Classes, below.)
M. SYSTEMS INCLUDING PILOT CONTROL MEANS:
Amplifiers including a pilot control frequency component in
the signal source which is used to control the amplifier are classified
herein.
Transmission Lines Combined With Pilot Control - Such subject
matter is classified elsewhere when provided with an auxiliary line
for the pilot control signal; for those systems in which the pilot
control signal is combined with the signal to be transmitted; with
an amplifier which is controlled must correct or maintain a predetermined
condition of the transmission line for classification
elsewhere. Otherwise classification is herein.
Pilot Frequency Controlled Repeaters - Such subject matter
is classified elsewhere.
N. GAS OR VAPOR TUBE CIRCUITS IN OTHER CLASSES:
Gas or vapor tube circuits are classified elsewhere. (See References
to Other Classes and Within This Class.)
O. TRAVELING WAVE TUBES AND CIRCUITS:
Classification of traveling wave tube amplifiers is in this class
when it includes the output or load circuit. Classification is otherwise
where no load or output circuit is claimed and the circuit means
which may be involved are an integral part of the tube. Oscillators
including a traveling wave tube are classified elsewhere. (See
References to Other Classes, below.)
P. AMPLIFIER AND A DETECTOR OR SUPERHETERODYNE CONVERTER
AND AN AMPLIFIER:
Such subject matter involves a subcombination peculiar to
radio receivers and is classified elsewhere with radio receivers
or inappropriate subclasses for
a demodulator with amplifier. When an amplifier and a detector
are claimed and the detector is claimed merely as a means to develop
a control signal and not for the purpose of detecting the intelligence
signal as a function of a receiver, classification is herein and
not in receivers. Where the same tube serves both as a detector
and an amplifier classification is not in this class but elsewhere. Demodulators,
depending again upon the type of demodulator involved, are classified
elsewhere. Combinations which comprise a reflex amplifier or a
superregenerative detector are classified elsewhere. (See References
to Other Classes, below.)
Q. VOLTAGE MAGNITUDE CONTROL SYSTEMS:
Voltage magnitude control (for single source energy systems)
such as line voltage control, etc., in general, is classified elsewhere
and includes current or load regulation, current and voltage limiting
systems, transformer and impedance systems for the purpose. See
LIMITERS, above. (See References to Other Classes, below.)
R. SYSTEM OR DEVICES CLOSELY RELATED TO OR ANALOGOUS TO AMPLIFIERS:
See References to Other Classes, below.
S. SYSTEMS UTILIZING AMPLIFIERS:
The great majority of electrical control or signaling systems
utilize amplifiers such as are classified herein or closely related
devices (as where the waveform of the input is not retained in the
output). Such systems include, also, mechanical systems with electrical
control means. In view of such widespread use no attempt is made
to list the classes of all or a large number of systems utilizing
amplifiers. Systems involving amplifiers in combinations where
the amplifier is invariably present, involve few additional elements,
or wherein the amplifier is usually an important component of the
combination are classified elsewhere.
Also see References to Other Classes, below.
T. ELEMENTS OR CIRCUIT NETWORKS COMMONLY USED IN AMPLIFIERS
OR AMPLIFIER SYSTEMS:
See References to Other Classes, below.
SECTION III - REFERENCES TO OTHER CLASSES
SEE OR SEARCH CLASS:
| 174, | Electricity: Conductors and Insulators,
subclasses 32+ for shielding means. (See Lines With Other Classes,
T, "Elements or Circuit Networks Commonly Used in Amplifiers," above.) |
| 250, | Radiant Energy, appropriate subclasses, for the detection of invisible
radiant energy or the testing of materials by invisible radiant
energy,
subclasses 200+ for photocell circuits and apparatus, particularly
subclass 214 for photocell controlled circuits including electron
tube circuits. (See Lines With Other Classes, S, "Systems
Utilizing Amplifiers," above.) |
| 257, | Active Solid-State Devices (e.g., Transistors, Solid-State
Diodes), for active solid state devices, per se.
(See Lines With Other Classes, T, "Elements or Circuit
Networks Commonly Used in Amplifiers or Amplifier Systems," above.) |
| 307, | Electrical Transmission or Interconnection Systems, for saturable reactor circuits for wave shaping, switching,
pulse production, etc., analogous to similar electronic tube circuits;
subclasses 401+ for nonlinear reactor systems. So called amplifier
circuits including a nonlinear capacitor as the amplifying device, which
have an A.C. source where the claims do not provide a filter to
remove the A.C. source from the output or where a demodulator is claimed
and no filter or other means to remove the A.C. power supply from
the signal output circuit is disclosed is classified in subclasses 401+.
(See Lines With Other Classes, D, "Saturable Reactor Circuits
(Magnetic Amplifiers)." E, "Nonlinear Reactor
Circuits." and R, "System
or Devices Closely Related to or Analogous to Amplifiers,"above.) |
| 313, | Electric Lamp and Discharge Devices, appropriate subclasses for the structure of vacuum tubes
and gas and vapor tubes. See the class definition of Class 313.
(See Lines With Other Classes, T, "Elements or Circuit
Networks Commonly Used in Amplifiers," above.) |
| 315, | Electric Lamp and Discharge Devices: Systems, for gas or vapor tube circuits in other classes;
see the classes specified in the Notes thereto for gas or vapor
tube circuits. (See Lines With Other Classes, N, "Gas
or Vapor Tube Circuits in Other Classes.") |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 3.5 , 3.6 or 39.3 for classification otherwise where
no load or output circuit is claimed and the circuit means which
may be involved are an integral part of the tube. (Lines With Other
Classes, O, "Traveling Wave Tubes and Circuits"). |
| 323, | Electricity: Power Supply or Regulation Systems, for passive networks which limit the signal amplitude
voltage or current. (Lines With Other
Classes, B, "Limiters.") |
| 323, | Electricity: Power Supply or Regulation Systems, for circuits which control voltage or current.
(See Lines With Other Classes, D, "Saturable Reactor Circuits
(Magnetic Amplifiers.") |
| 323, | Electricity: Power Supply or Regulation Systems, for voltage magnitude control (for single source
energy systems) such as line voltage control, etc., in general (see
the class definition). (Lines With Other Classes, "Voltage Magnitude
Control Systems"). |
| 324, | Electricity: Measuring and Testing,
subclasses 123+ for amplifiers with meters. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 309+ for miscellaneous limiting circuits with active
device elements. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 100+ for wave conversion circuits, subclasses 291+ for
miscellaneous pulse generating systems, and subclasses 365+ for
electronic tube gating circuits. (Lines With Other Classes, C, "Miscellaneous
Electronic Tube Circuits.") |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for transistor circuits which
are not amplifiers or not combined with an art device or in a system
specifically provided for in some class. (See Lines With Other
Classes, F, "Miscellaneous Transistor Circuits.") |
| 329, | Demodulators, appropriate subclasses for a demodulator with amplifier.
(See Lines With Other Classes, P, "Amplifier and a Detector
or Superheterodyne Converter and an Amplifier" and S, "Systems
Utilizing Amplifiers," above.) |
| 329, | Demodulators, where the same tube serves both as a detector and
an amplifier, depending upon the type of demodulator involved.
(Lines With Other Classes, P, "Amplifier and a Detector
or Superheterodyne Converter and an Amplifier"). |
| 331, | Oscillators, are in the most common types, in a sense, merely
positive feedback amplifiers without an input, and therefore the
circuits, structures, and problems are often closely related to
those of amplifiers. (See Lines With Other Classes, R, "System
or Devices Closely Related to or Analogous to Amplifiers," above.) |
| 331, | Oscillators, where specific details of the generator or oscillator
are claimed; in such cases classification is with the type of generator claimed
or with oscillators. (See Lines With Other Classes, G, under "Generator
or Oscillator Claimed by Name Only," and I, "Oscillator
as a Load for an Amplifier," above.) |
| 331, | Oscillators, for oscillators including a traveling wave tube;
subclass 82 for traveling wave type. (Lines With Other Classes,
O, "Traveling Wave Tubes and Circuits"). |
| 332, | Modulators, appear, usually as no more than amplifiers which
have an input source in addition to the signal (i.e., the carrier).
(See Lines With Other Classes, R, "System or Devices Closely
Related to or Analogous to Amplifiers," above.) |
| 333, | Wave Transmission Lines and Networks, appropriate subclasses, particularly
subclasses 24+ , for passive wave filters and coupling networks.
(See Lines With Other Classes, T, "Elements or Circuit
Networks Commonly Used in Amplifiers or Amplifier Systems," above.) |
| 333, | Wave Transmission Lines and Networks,
subclasses 213+ for networks containing an active element (amplifying
device). (See Lines With Other Classes, A, "Two-Terminal
Negative Resistance Networks," above.) |
| 333, | Wave Transmission Lines and Networks,
subclass 14 for companders. Subcombinations involving connection
or maintenance of a predetermined condition of the transmission
line are classified in Class 333. (See Lines With Other Classes,
L, "Companders Including Amplifiers.") |
| 333, | Wave Transmission Lines and Networks,
subclass 15 , when provided with an auxiliary line for the pilot
control signal, subclass 16 for those systems in which the pilot
control signal is combined with the signal to be transmitted and
also subclass 16 with an amplifier which is controlled must correct
or maintain a predetermined condition of the transmission line.
(Lines With Other Classes, M, under "Transmission Lines
Combined With Pilot Control," above.) |
| 333, | Wave Transmission Lines and Networks, for electric wave transmission systems, passive wave
transmission networks, passive coupling networks and terminating
networks, smoothing type wave filters, networks including a wave transmission
device, passive networks for producing an output wave, systems including active
elements, and wave traps using long line elements. (Lines With
Other Classes, K, "Amplifiers Combined With Long Line Transmission
Means or Distributed Parameter Elements, and Amplifiers Combined
With Wave Filters, Equalizers or Attenuators"). |
| 334, | Tuners, appropriate subclasses for tuners, per se. (See
Lines With Other Classes, T, "Elements or Circuit Networks
Commonly Used in Amplifiers," above.) |
| 336, | Inductor Devices, appropriate subclasses for the structure of transformers
and inductor devices, generally. (See Lines With Other Classes,
T, "Elements or Circuit Networks Commonly Used in Amplifiers
or Amplifier Systems," above.) |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 196+ for electric circuits including transistors, subclasses
199+ and 205 for electric circuits including space discharge
devices combined with relays as the load therefor, and subclass
204 for electric circuits including saturable reactors, wherein
the transistor, space discharge, or saturable reactor circuit may
be an amplifier. (See Lines With Other Classes, S, "Systems
Utilizing Amplifiers", above.) |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 271+ and 500+ for capacitor structure, per
se. (See Lines With Other Classes, T, "Elements or Circuit
Networks Commonly Used in Amplifiers or Amplifier Systems," above.) |
| 379, | Telephonic Communications,
subclasses 338+ for devices known in the art as repeaters which are
in effect two-way amplifiers. (See Lines With Other Classes, J, "Repeaters," above.) |
| 381, | Electrical Audio Signal Processing Systems and
Devices,
subclasses 111+ for miscellaneous systems which include combinations
of amplifier and loud speaker or microphone and amplifier which
limits the system to use with a particular art even though the source
is claimed by name only; for distribution systems, involving a
central broadcasting system from which programs are distributed
to local stations where the programs are amplified and reproduced; also
for where the load is claimed, broadly, or by name only as a specific
electrical art device, as for example, as a loudspeaker. (See
Lines With Other Classes, G, "Amplifier Combined With Specific
Source of Signal Energy," H, "Amplifiers Combined
With Specific Load," and S, "Systems Utilizing
Amplifiers," above.) |
| 398, | Optical Communication,
subclasses 1 through 8for light wave communications. (See Lines With
Other Classes, S, Systems Utilizing Amplifiers, above.) |
| 455, | Telecommunications,
subclasses 130+ for radio receivers which may be limited to an amplifier
and a detector; subclass 351 for portable radio receivers. (See
Lines With Other Classes, S, "Systems Utilizing Amplifiers," above.) |
| 455, | Telecommunications, appropriate subclass, particularly
subclass 335 , where the same tube serves both as a detector
and an amplifier. Class 455, subclass 342, includes combinations which
comprise a reflex amplifier or subclasses 336+ for combinations
which comprise a superregenerative detector. (Lines With Other
Classes, P, "Amplifier and a Detector or Superheterodyne
Converter and an Amplifier") |
| 455, | Telecommunications,
subclasses 130+ for a subcombination peculiar to radio receivers classified
with radio receivers. (See Lines With Other Classes, P, "Amplifier
And a Detector or Superheterodyne Converter And An Amplifier.") |
| 505, | Superconductor Technology: Apparatus, Material,
Process,
subclasses 150+ for high temperature (Tc
30 K) superconducting device; and particularly subclass 180 for maser-type
amplifying device, or subclasses 191+ for semiconductor
device. (See Lines With Other Classes, R, "System or Devices" Closely
Related to or Analogous to Amplifiers, S, "Systems Utilizing
Amplifiers", and T, "Elements or Circuit Networks
Commonly Used in Amplifiers,"above.) |
SECTION IV - GLOSSARY
ACCEPTOR IMPURITY OR ACCEPTOR
A material which when added to a semiconductor material
in minute quantities, as an impurity, induces hole conduction, generally
causing the semiconductor to be one of "P-type conductivity".
ACTIVE NETWORK
A network containing a source of energy, or a sink of energy
(i.e., a device for absorbing or dissipating energy other than that
accounted for by the resistance of the components of the networks).
Merely dissipating the heat generated by a resistance will not
cause the resistance to be an active element. See Amplifying Device.
AMPLIFIER
Electric circuit means wherein a variable electrical
current or voltage input signal is applied to an electrical amplifying
device to control a source of electrical energy applied to the same
device and from which is derived an output signal of substantially
the same wave form as the input signal and substantially linearly related
thereto.
AMPLIFIER CHANNEL OR CHANNEL
A part of an amplifier system in which a single signal path
may be traced from a source to a load, and which path includes an
amplifier as defined above. Such channel may be a cascade amplifier.
AMPLIFYING DEVICE
An electrical transducer of the active type wherein the electrical
energy supplied by one system (power supply) is controlled by the
electrical energy supplied by another system (signal source) limited
to the active transducer device element itself such as a vacuum
tube, transistor, controllable gas tube, saturable reactor, variable
resistive element, etc.. See Active Elements.
AMPLITUDE LIMITER
A means in a circuit to limit the amplitude of the electrical
voltage across it or the current in it to a value below or above
a fixed predetermined value, particularly the former.
ANODE
An electrode which acts as the positive terminal of an electric
discharge or which acts as the positive terminal of an electric
field to cause a discharge or accelerate the electrons in an electric
discharge.
ATTENUATOR
Devices and networks consisting of one or more elements
which exhibit only a positive resistance effect and which reduce
the intensity of the energy passing through the device by dissipation,
(1) the elements being proportioned to permit a change in their
value to control the energy loss while maintaining substantially
constant input and/or output impedance of the device, and/or
(2) the elements being proportioned to permit the device to be inserted
in the circuit to provide an energy loss without introducing any
reflections in the circuit, and/or (3) the elements being
combined with a long line or long line element, and/or
(4) the device or network having an impedance equal to the impedance
of a specified long line, and/or (5) the device or network
is claimed as being particularly modified for use over a frequency band
so that its characteristics are particularly related to frequency.
AUXILIARY GRID
Any grid, of an electronic tube other than the signal input
grid.
BALANCED CIRCUIT
A circuit having its conductors electrically symmetrical with
respect to a reference potential plane (e.g., ground). The potential
between the two sides and ground are equal and of opposite sign.
For example, a horizontal two-wire line may be a balanced line.
See Push-Pull Stage.
BASE ELECTRODE
See the definition of point contact or junction transistor above.
BIAS, BIAS VOLTAGE, BIAS CURRENT
In an amplifying device, usually, a steady D.C.. voltage or
current applied between two electrodes usually referred to the input
electrodes to form an electric reference means for the control means,
which influences the current flow of an electronic tube or semiconductor device
or the flux relationships of a magnetic saturable reactor. See
also Bias Control and Power Supply.
BIAS CONTROL
Control, as defined above applied to control of bias
voltage or current of an amplifying device. This is distinguished
from signal feedback in that the bias control voltage or current
has a smoothed average value which adds to or subtracts from the
bias voltage or current and is unlike the signal feedback voltage
which varies instantaneously with the signal at the point from which it
is derived. See also, Bias, Bias Voltage or Bias Current.
CASCADE AMPLIFIER
A series of amplifiers wherein the input for each amplifier
except the first (to which the electric signal source is connected)
is coupled from the output of the prior amplifier.
CATHODE OR CATHODE ELECTRODE
The negative electrode of the two electrodes of an electronic
tube between which an electric discharge occurs (for negative charge
carrier particles); in a vacuum tube the electrode which emits the
electrons and is negatively charged with respect to the electrode
which collects the electrons.
CATHODE-HEATER
A filament in proximity to an indirectly heated cathode with
terminals designed to receive a source of power to heat the cathode
to its electron emitting temperature.
CATHODE IMPEDANCE
The impedance from the cathode of an electronic tube
to ground or a reference potential.
CHARGE CARRIER PARTICLE
A charged particle of matter involved in a flow of space current
(electric discharge) and by means of which such current flows (current
flow other than an electromagnetic wave propagated in open or confined
space). Such charge carrier particles may be ions of a gas or charged atomic
particles such as electrons.
COLLECTOR ELECTRODE
See the definition of point contact or junction type
transistor below.
COMPRESSOR OR VOLUME COMPRESSOR
A device that compresses the volume range, as in recording
sound, radio-telephone transmission, etc.. In compressing the signal
volume range the amplification of large signals is reduced and of
small signals is increased.
CONFIGURATION
The arrangement of electrodes of a transistor as input and
output electrodes, e.g., common base configuration, where the base
is included in both the input and output circuits of a transistor
amplifier.
CONTROL
A selective adjustment of an element of an amplifier
to vary the operation of the amplifier in a desired manner, or the
characteristic of a part of the amplifier whereby in response directly
to signal, or by means of a developed voltage or current in response
to the signal, or by a voltage from some outside source, the impedance
characteristics of a circuit element, or the electrical characteristics
(bias or energizing voltage) of an amplifying device are automatically
altered to change the operation of the amplifier in a predetermined
manner. Such control may be by a nonlinear impedance element alone
in a biasing or power supply circuit. The term control has not
been applied in this class, when a nonlinear impedance element is
in the signal path and affects the signal only, without any control
from a separate path being applied to vary such impedance.
CONTROL ELECTRODE
An electrode designed to influence or control the discharge
current flowing between other electrodes. It may depend for its
effect on either its electrostatic effect or on the current flow
thereto. The most common types of control electrodes are the signal
control grid, or the gain control electrode or grid.
CONCENTRIC LINES
A transmission line in which one conductor extends within
a second hollow conductor.
CONTROL GRID
A control electrode having grid construction.
D.C. COUPLING
A signal coupling network including a D.C.. conductive path.
In a four terminal network such paths must be traced between terminals
on the circuits to and from which the coupling is made which vary
in voltage with the signal (this excludes D.C.. paths limited to
ground leads or D.C.. shunt paths).
D.C. PATH OR D.C. CONDUCTIVE PATH
A path for current in a network which can conduct D.C.. current.
DELAY NETWORK
Networks including significant structure for retarding wave
energy a predetermined period of time over a range of frequencies.
DIODE
Refers to any electronic tube, solid element, semiconductor,
barrier layer device or other current carrier means limited to two
electrodes and without additional magnetic or electrostatic means
to influence the current flow, and which has marked unidirectional
current characteristics.
DIRECTLY HEATED CATHODE OR FILAMENTARY CATHODE
A filament designed to have its terminals connected to
a source of current, the filament being heated by the current passing
through it and effective to emit electrons, designed to serve as
a cathode of an electronic tube as defined above.
DISCHARGE PATH
The path of the free electrical charge carrier particles between
the electrodes of an electronic tube.
DISTRIBUTED PARAMETER CHARACTERISTICS
A conductor or conductive means designed to operate at microwave
or other high frequencies, so that the conductive means exhibits
both distributed capacitance and distributed inductance at such
frequencies.
DISTRIBUTED PARAMETERS
When the impedance of a transmission device or line at the
operating frequency or band of frequencies is due primarily to the
parameters of the device or line itself, and in considering the
inductance, capacitance and resistance of the device or line they
must be considered as mixed together and spread out along the device
or line rather than being considered as in separate discrete lumps
or devices as in the case of simple series and parallel circuits,
the transmission device or line may be said to have distributed
parameters. Examples of circuits with distributed parameters include
telephone, telegraph and power lines for high frequency energy.
DONOR IMPURITY OR DONOR
A material which when added to a semiconductor in minute
quantities, as an impurity, induces electron conduction, generally
causing the semiconductor to become one of "N-type conductivity".
ELECTRIC CARRIERS OF A TRANSISTOR
Current flow in a transistor may be by negative carriers (electrons)
or positive carriers (holes).
ELECTRIC DISCHARGE
The flow of current between two spaced electrodes at different
potentials or the charge carrier particles conveying the current
from one spaced electrode to the other.
ELECTRIC SIGNAL SOURCE OR SIGNAL SOURCE
The source of electrical signal energy to be amplified
or the source of electrical signal energy which controls the electric
power supply applied to the amplifying device.
ELECTRICAL CIRCUIT
An electrical network providing one or more closed paths.
ELECTRICAL NETWORK OR NETWORK
An arrangement of electrically connected electrical elements
and/or devices which are capable of carrying electric A.C.
or D.C. current. Note. A network does not define the structure
in space of the network elements or their arrangement in space relative
to each other; it merely defines the elements or devices broadly
by type as to the electrical function they perform and the electrical
connections which will carry current between such elements and/or
devices.
ELECTRODE
(1) In a vacuum tube, electronic tube or in any discharge
device, the conductive elements between which the electric discharge
takes place, and to which the power supply is applied; any additional
conductive means placed in proximity to the electric discharge and/or
other electrodes to affect electrostatically the discharge or the
potentials of the electrodes with which they are in proximity.
(2) In a magnetic amplifying device or in a resistive amplifying
device, (including semiconductive devices) the terminals of windings which
influence the operation of the magnetic device or the resistor or
semiconductor terminals by means of which electric current may flow
in or out of the resistor or semiconductor or by means of which
a potential may be applied to the resistor or semiconductor.
ELECTROMECHANICAL TRANSDUCER
Means to convert the electric signal to mechanical vibrations
and means further to convert the mechanical vibrations back to electric
signals, such means generally serving as either time or phase delay
means or means to determine the transmission frequency of the coupling network.
ELECTRONIC TUBE
An electric space discharge device, that is, a device
in which electricity flows from one electrode to another by means
of free electrical charge carrier particles traveling in a vacuum,
gas or vapor; included are electric space discharge devices (also
called electronic tubes) which operate in the open, i.e., not in
an enclosed envelope. The electrical charge carrier particles may
be of any type, usually electrons for vacuum tubes or charged ions for
gas or vapor tubes.
EMITTER ELECTRODE
See the definition of point contact or junction type
transistor in this Glossary.
EQUALIZER
Networks with attenuation or attenuation and phase distortion
characteristics which vary over a frequency range for use in a wave
transmission system for modifying the attenuation or attenuation
and phase characteristics of the wave energy as a function of frequency.
EXPANDER OR VOLUME EXPANDER
A device that expands the volume range, as in recording sound,
radio-telephone transmission, etc. In expanding the signal volume
range, the amplification of large signals is increased, and the
amplification of small signals is reduced. Expanders are used generally
to restore a signal after compression.
GRID
Is used in the conventional sense referring to the intended
use and structure of the element in an electronic tube, particularly
in a vacuum tube.
FILAMENT
A wire, ribbon, or rod conductive member.
FILTER
A frequency selective means.
FREQUENCY RESPONSIVE MEANS
Circuit means which acts on the signal to affect some frequency
component of the signal differently from any other frequency components
of the signal, for example, a tuned circuit or filter circuit which
eliminates a frequency component, or an equalizer which emphasizes the
signal amplitude of some frequency or frequency range of the signal
with respect to others (e.g., tone control). See also, Frequency
Selective Means, below.
FREQUENCY SELECTIVE MEANS
Network means composed of some reactive elements which
permit the passage of certain frequency components or a frequency
component and block others. See also, Frequency Responsive Means.
GAIN
The ratio of the amplifier output power, voltage, or
current to the amplifier input power, voltage or current.
GAIN CONTROL ELECTRODE
An electrode designed, together with the electron tube
in which it is incorporated, to receive a D.C.. control voltage
(other than the signal but which is usually derived from the signal),
whereby changes in the control voltage change the gain of the tube.
GAS OR VAPOR TUBE
An electric discharge device which depends, for its operation,
at least in part, upon ionization of a gas or vapor.
GRID OR GRID ELECTRODE
An electrode having one or more apertures therein, usually
formed of open-work material such as wire mesh, etc.., and usually
used as the signal or control electrode, or auxiliary electrode
of an electron tube.
IMPEDANCE MATCHING NETWORK
Coupling networks which include one or more impedance
elements construed or proportioned to substantially eliminate the
reflected wave energy between the network and at least one of the
connected circuits caused by impedance differences.
INDIRECTLY HEATED CATHODE (equiptential cathode)
A cathode designed to be heated to its emitting temperature
by a separate heating element.
INPUT CIRCUIT OR COUPLING
The circuit or network of an amplifier extending from the
source of electrical signal to the input electrodes of the amplifier,
which may include the source of electrical signal.
INTERELECTRODE CAPACITANCE
The capacitive reactance for signal flow between any two
electrodes of a vacuum tube, transistor or similar device inherent
in their relationship to each other electrostatically and which
for certain frequencies and voltages forms a path for the signal
current usually detrimental to the operation of the circuit.
INTERELECTRODE IMPEDANCE
An impedance between electrodes of a vacuum tube, transistor,
or similar device inherent in its structure, and manner and frequency
of operation. This term is generic to inter-electrode capacitance
above; and includes also input conductance caused by the transit time
of electrons, etc.
INTERSTAGE CIRCUIT OR COUPLING
The electrical circuit or network by means of which the output
signal from the output electrodes of the amplifying device of one
stage of a cascaded amplifier is conveyed to the input electrodes
of the amplifying device of the following stage of the cascade amplifier.
INTRINSIC CONDUCTIVITY
Refers to a semiconductor material which for a certain range
of conditions has its free electron carriers and free hole carriers
in approximate balance, so that the semiconductor material is neither
N- nor P-type. Sufficient change in temperature or sufficient radiant
energy impinging upon such a body will upset this equilibrium.
JUNCTION IN A TRANSISTOR OR SEMI-CONDUCTOR
The boundary of P-type and N-type semiconductor material.
JUNCTION TRANSISTOR
A transistor comprising two P-N Junctions back-to-back wherein
a region of P- or N-type semiconductor material is common to both
junctions (thus determining an NPN or a PNP junction transistor,
respectively); an emitter electrode connected to one of the conductivity regions
not common to the two junctions, normally forwardly biased (positive
terminal of bias means to emitter for PNP type and negative terminal
for NPN type); a collector electrode connected to the other conductivity region
but common to the two junctions, reversely biased (negative terminal
of bias means for the PNP type and positive terminal for the NPN
type; and a base electrode connected to the region common to both
junctions. See definition of Point Contact Transistor, which operates
similarly in many respects.
LECHER LINES
A parallel transmission line with means to tune the parallel
line.
LOAD
The electric device or circuit which utilizes the output signal
derived from the amplifier after the input signal has controlled
the electric power supply by means of the amplifying device to yield
a signal which is a replica of the input signal but usually of greater
amplitude.
LONG LINE
A wave transmission device or line having distributed parameters
and especially designed to propagate electrical wave energy where
the wave length of the transmitted energy is relatively short when
compared with the length of the transmission line or device. The
impedance of a long line is practically fixed by the constants of
the line itself. The length of the transmission line or device
may be a multiple or a fraction of a wave length, e.g., 1/4,
1/2, etc., or otherwise have its length proportioned to
the wave length of the energy with which it is to be used.
LONG LINE ELEMENT
A circuit element having distributed parameters, such
as a resonator, or a wave guide. A long line element may be a part
of a long line wave transmission device or used in a network with
other circuit elements of the lumped parameter type, for example,
as in the case of delay networks, impedance matching networks, wave
filters.
LOOP PATH
In an amplifier having signal feedback, the path of the signal
from the input point where the signal feedback is applied forward
through the amplifier to the point in the circuit from which the
signal feedback is derived through the signal feedback path to the
aforesaid input point.
MAJORITY CARRIERS
See the definition of N- or P-type conductivity below.
MINORITY CARRIERS
See the definition of N- or P-type conductivity below.
NEGATIVE FEEDBACK
Signal feedback having at least some component thereof in
opposite phase with the signal at the point where the signal feedback
is applied.
N-TYPE CONDUCTIVITY
The characteristic of a semiconductor material, usually imparted
by the addition of impurities of the "donor" type,
of an excess of free electrons over holes (free positive charges)
at any time at room temperature, such negative charge carriers or
electrons being referred to as majority carriers for current flow
in such material, and holes as minority carriers for such current
flow.
NEUTRALIZATION MEANS
Circuit means to eliminate, mitigate, or lessen undesirable
effects of inter-electrode capacitance or inter-electrode impedance
and which may include the input and/or output impedance
of the amplifying device involved (such input or output impedance
includes the inter-electrode impedance of the input or output electrodes).
NONLINEAR IMPEDANCE OR DEVICE
An impedance or device, which may be reactive or resistive
or a combination of both and having the characteristic that for
changes in voltage or current, the relationship of the voltage drop
across the impedance or device, or the voltage applied across the
impedance or device to the current flowing through it, is nonlinear.
OUTPUT CIRCUIT OR COUPLING
The circuit or network of an amplifier extending from the
output electrodes of the amplifier to the load device, which may
include the load.
PARASITIC REACTANCE, IMPEDANCE, CAPACITANCE, OR INDUCTANCE
Impedance characteristics of capacitive or inductive nature
which are exhibited by conductive elements or conductive parts of
a circuit at only high frequencies in a circuit designed for operation
over a wide band and are inherent in the construction of such element
or part. The presence of such reactances is undesirable and generally
detrimental to the proper operation of the circuit. When a parasitic
reactance is used as though it were a predetermined lumped reactance
as in the case of the distributed capacitance of a coil being used
to resonate therewith at a particular frequency; the distributed capacitance
or other parasitic reactance is treated, for classification purposes,
as though it were a predetermined lumped reactance in the circuit.
Inter-electrode capacitances similarly involved in amplifiers as
part of a tuned circuit are similarly treated.
PASSIVE NETWORK
A network containing no source of energy and in which no
energy is dissipated other than that accounted for by the resistance
of the components of the network.
PHASE SHIFT
Used to designate the change in phase relation between voltage
and current of the same wave energy, or between the voltages or
the currents of different wave energy of the same frequency.
POSITIVE FEEDBACK
Signal feedback having at least some component thereof in
phase with the signal at the point in the amplifier circuit where
the signal feedback is applied.
POTENTIOMETER
A network which permits the division of a voltage applied
across it, including adjustable means to select a particular division
of the voltage applied across the network.
POWER SUPPLY
The source of electrical energy applied to an amplifying device
which is controlled by the electric input signal. The term is used
herein generically to include also a cathode heater supply, and
bias voltage or current supply.
PLURAL AMPLIFIER CHANNELS
An amplifier system having at least two signal channels each
containing separate amplifiers as defined above (wherein each amplifier
may be a cascade amplifier), such amplifier channels may be completely
separate from each other having separate and independent sources
or loads; usually with some common control or they may be in parallel,
having a common source and a common load; or the plural channels
may be in branched circuits from separate sources or to separate loads.
POINT CONTACT TRANSISTOR
A transistor comprising a body of P- or N-type semiconductor
material to which are attached two closely spaced electrodes connected
at sharply defined points to the semiconductor material and a third
electrode, the base relatively remote from the other electrodes
and having a relatively large contact area (low resistance) for
connection to the semiconductor. In this type of transistor the emitter
is forwardly biased having, in N-type semiconductor material, the
positive terminal of the biasing means connected to the emitter
electrode, and for P-type semiconductor material the negative terminal
of the biasing means connected to the emitter relative to the base,
to inject minority carriers for the conductivity type semiconductor
material (holes for N-type and electrons for the P-type) and the
collector is biased reversely (having the negative terminal of the
biasing means connected to the collector for N-type material and
the positive terminal for P-type material), relative to the base
so that minority carriers are collected there.
P-TYPE CONDUCTIVITY
The characteristic of a semiconductor material, usually imparted
by "acceptor" type impurities therein, of an excess
of free positive carriers (holes) over free negative carriers (electrons),
such positive carriers or holes being referred to as majority carriers
for current flow in such material and the electrons as minority
carriers for such current flow.
PUSH-PULL STAGE
Includes two amplifiers each as defined above under "AMPLIFIER",
the input electrodes of each of the amplifying devices of the two
amplifiers being balanced to ground or some other convenient electrical
reference plane, the source of electrical signal being such, and
so coupled to the input electrodes, that at any instant the signal
on each input electrode is substantially equal and opposite in sign
to the signal on the other input electrode; and wherein the signal
on the output electrodes of each of the amplifying devices is similarly
balanced to a convenient electrical reference plane.
| | (1)
Note. A balanced signal circuit is treated in this class
as a special case of a single source or a single load. See Balanced
Circuit. |
| | (2)
Note. A push-pull amplifier is treated in this class as a
single channel, having a single source and a single load. |
REACTIVE COUPLING
A coupling network including reactive means which may
be inductive or capacitive.
RECTIFIER
A device with a unilateral current characteristic which permits
the passage of only D.C. current therethrough, and which is used
to convert A.C. current applied thereto to D.C. current.
RESONANT CIRCUIT
A circuit containing both inductive and capacitive reactance
and in which the inductive reactance equals the capacitive reactance
for a particular frequency. The resonant circuit may be series
resonant, where the reactive elements are in series; or parallel
(anti-resonant), where the inductive and capacitive elements are
in parallel. See also, Resonator.
RESONATOR
Devices comprising conductive enclosures, cavities, or wave
transmission line sections of the two terminal type, and having
distributed inductance and capacitance, the line sections being
terminated in other than the characteristic impedance of the line
sections, the devices presenting resonant characteristics to the
existing source of wave energy. See also Resonant Circuit.
SATURABLE REACTOR
An inductive device having a core and at least one winding
thereon in which the inductance is variable in accordance with magnetomotive
force applied, up to a limiting value beyond which increased magnetomotive force
does not change the inductance.
SCREEN GRID
A grid electrode placed between the control grid and
the anode of a vacuum tube to reduce inter-electrode capacitance.
SECONDARY EMISSION ELECTRONIC OR VACUUM TUBE
A tube which depends for its operation, at least in part, upon
the emission of electrons from a body due to collision of higher
energy electrons with the body.
SECONDARY EMISSIVE ELECTRODE
An electrode which emits electrons upon collision with higher
energy electrons. Since all electrodes have this characteristic,
the term applies only to those electrodes designed to have an electron
stream or beam impinge thereon to emit a stream or beam of secondary
electrons.
SEMICONDUCTOR
A material having a specific resistance value of the order
of that of germanium, silicon, selenium, etc.; or insulators whose
specific resistance is reduced in value to the aforesaid range in
operation, by alpha particle or electron bombardment or other means,
so that the insulators operate broadly as semiconductors in an electrical circuit.
SEMICONDUCTOR AMPLIFYING DEVICE
An amplifying device constructed of a semiconductor with
suitable electrodes for the application of signal current, power
supply energy, and for the derivation of output signal current.
SIGNAL
A variable electrical current or voltage having characteristic
variations in time, which characteristic variations are transmitted
through an electrical network from a source in which the signal
originates to a load where the signal is utilized.
SIGNAL ELECTRODE OR SIGNAL GRID
The electrode to which the signal is applied; in the
case where such electrode is a grid electrode, the signal grid.
SIGNAL FEEDBACK
The application of a signal derived from an output electrode,
to an input electrode of an amplifier or a prior stage of an amplifier.
The input and output electrodes of the feedback may be the same
or a common electrode as where vacuum tube space current flows through
an unbypassed cathode impedance to change the potential on the cathode
with respect to the control grid in accordance with the signal output.
(For the distinction between signal feedback and bias control see
the definition thereof, above).
SIGNAL FEEDBACK PATH
Circuit means to apply a portion of the electrical signal output
of an amplifier to the input of the amplifier involving a shared
impedance for the input and output circuits.
STABILIZATION MEANS
In an amplifier having a tendency to depart from a predetermined
condition of operation, any circuit means used to maintain such
predetermined condition of operation of the amplifier. See the
definition of Control above.
STRUCTURE
Refers to any details of a circuit element as to the
nature or composition of the material or materials of which it is made,
the form or shape of the element or its parts or the relationship
in space of such elements or parts or such characteristics of the
elements relative to each other.
SWITCH
A device or means for opening or closing an electric
circuit.
THERMALLY RESPONSIVE IMPEDANCE
An impedance element whose impedance value is responsive
to the temperature changes therein by reason of the heat generated
by the current flow therethrough, or the ambient temperature of
the impedance element, or whose impedance value may be changed by
separate electrical control means or other heat control means.
TRANSISTOR
An amplifying device comprising a semiconductor material
to which contact is made by three or more electrodes.
UNBALANCED CIRCUIT
A circuit having its conductors electrically unsymmetrical
with reference to a potential plane. For example, a concentric line
is ordinarily unbalanced, the outer conductor being ordinarily connected
to ground.
VACUUM TUBE
An enclosed space evacuated of most of its gas wherein an
electric discharge takes place between two electrodes one of which
emits electrically charged atomic particles, generally electrons
and the other electrode collects such particles. The vacuum tube
has at least one additional electrode or other means to control
the flow of charged atomic particles between the emitter electrode
and the collector electrode. The electric discharge of a vacuum tube
is normally an electron discharge and any discharge of ionized particles
is normally fortuitous and unintended. A vacuum tube is usually
involved in a four terminal network, the input signal being supplied
to two input electrodes usually the grid (control) and cathode (electron
emitting electrode) and the output circuit normally being comprised
of the power supply, the anode load impedance, the anode, the electron
discharge, the cathode impedance, the load and the output coupling means.
Thus the cathode which is normally present in the output and input
circuits is normally the common electrode. Other alternative configurations
where the input and output electrodes are not as above, as for example,
where the anode is a common electrode and the cathode is the output
electrode, are known and provided for in the schedule of this class.
The terms for the grid, cathode and anode electrodes or auxiliary
electrodes (as defined below) are referred to according to the predetermined
use usually assigned for them regardless of the alternative circuit
arrangements involved. The terms input, output, and common electrodes
are used as in these definitions.
WAVE ENERGY
An undulatory disturbance propagated through a medium,
(usually periodic in nature), its displacement varying periodically
with respect to time or distance or both. The wave may be manifested
in electrical, mechanical or acoustical form. However, in this
class the term "wave energy" refers only to electrical
wave energy.
WAVE GUIDE
A transmission device designed to propagate electrical waves
having an electric or magnetic field component extending in the
direction of propagation. The wave guide may be a hollow dielectric
or metal tube, or a solid dielectric rod, the wave energy being
propagated along the interior of the tube or rod and confined by
the walls of the tube or rod.
WAVE TRANSMISSION DEVICE
Any device which is used to guide or constrain electrical wave
energy and to convey the energy from one place to another. Included
are conductors, wave guides, resonant structures (e.g., cavities,
etc.).
SUBCLASSES
![[List of Patents for class 330 subclass 1]](../ps.gif) 1 | WITH DIVERSE-TYPE ART DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifier is combined with other
devices or structures having an added purpose or independent utility, other
than to perfect the amplifier, and in which the utility of the art
device is not destroyed by removal of the amplifier and which combination
is not provided for elsewhere.
| | (1)
Note. An example of art classifiable in this class and subclass
is an amplifier combined with an automobile accelerator pedal to
control the volume of the amplifier. The removal of the amplifier does
not destroy the utility of the accelerator pedal (as it would in
case of a radio receiver which included the amplifier or a part
thereof). |
| | (2)
Note. Subject matter in which a source is claimed by name
only as a specific art device, as for example, a microphone, is classified
with the specific art device and not with amplifiers. Subject matter,
in which the signal source device may be broadly claimed, not by
name, but by some distinctive identifying feature thereof as, where
a microphone source is claimed as a "means for converting sound
signals", is not classified with amplifiers, but with the
distinctive art device. |
| | (3)
Note. The terms generator or oscillator in claims, where
they appear as sources of signal energy without further qualification
except by their electrical characteristics such as impedance, reactance, etc.,
are treated as generalized sources of signal energy and classification
is with amplifiers except where specific details of the generator
or oscillator are claimed; in such cases, classification is with
the type of generator claimed or with oscillators in Class 331. |
| | (4)
Note. Where the load is claimed, even broadly, or by name
only as a specific electrical art device, as for example, a loudspeaker,
classification is not in this class, but with the load art device claimed.
Where characteristics of the load device are claimed, which are
peculiar to the disclosed electrical art device or to a specific
type of electrical art device, classification is with the load art device
established in the claim. |
| | (5)
Note. Subject matter wherein general electrical characteristics
of the load are claimed, as for example, "a load having a
variable impedance", is classified in this class. | |
| | |
| 2 | WITH AMPLIFIER CONDITION INDICATING OR TESTING MEANS: |
| | This subclass is indented under the class definition. Subject matter involving means or methods of testing amplifiers
as set forth in the class definition and/or amplifiers
as set forth in the class definition combined with indicating means
to show a condition of the amplifier.
| | (1)
Note. Amplifiers combined with a meter or indicating means
not involving a condition of the amplifier but where the amplifier
is merely an instrument in facilitating such indication, are not
classified in this class and subclass but in the appropriate subclass
of Class 324, Electricity: Measuring and Testing or Class 340,
Communications: Electrical, unless they are specialized for use
in the testing of a specific electronic art device in which case,
classification is generally with the specific electrical art device. |
SEE OR SEARCH CLASS:
| 324, | Electricity: Measuring and Testing, appropriate subclasses for electrical measuring
and testing. See (1) Note, above. |
| 340, | Communications: Electrical, appropriate subclasses for systems with signal or alarm
indicating means particularly
subclasses 500+ . See (1) Note, above. |
|
| | |
| 3 | WITH PLURAL DIVERSE-TYPE AMPLIFYING DEVICES: |
| | This subclass is indented under the class definition. Subject matter including at least two amplifying devices
each of which is of a type different from the other.
| | (1)
Note. When each of the amplifying devices is of a type which
is classified in different subclasses of this class providing for
such different types of amplifying devices, such as subclass 8 for saturable
reactor type and subclass 44 for electron beam type, classification
is in this subclass. Where the different types of amplifying devices
are types provided for in coordinate subclasses indented under a
major genus type, classification is not in this subclass, but in the
appropriate subclasses indented under subclass 250. Diverse type
vacuum tube amplifying devices combined in an amplifier are classified
in subclass 3 when each of the diverse type amplifying devices is
of a type separately provided for by a subclass in this class, as for
example, a traveling wave type amplifier classified in subclass
43 and an electron beam tube amplifying device classified in subclasses
44+. Where different types of vacuum tubes are involved,
only one of which is provided for by a separate subclass, classification is
not in subclass 3 but in the subclass providing for an amplifier
having an amplifier device of that type. Combinations of vacuum
tube and gaseous tube amplifiers are classified herein. Diode vacuum
tube amplifiers combined with any other type of vacuum tube amplifier, whether
provided for as a separate subclass or not, are classified herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 150, | for cascaded vacuum tube amplifiers with amplifier
devices having different characteristics (both amplifying devices
being of the same general type). |
| 299+, | for transistor amplifiers including combined diverse
type semiconductors. |
| 310, | for plural cascaded stage transistor amplifiers
including transistors having different characteristics. |
|
| | |
| 4 | WITH MASER-TYPE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device combines (1)
a substance having the characteristic that certain molecular, atomic,
or nuclear particles thereof are capable of excitation to a higher
energy level; (2) means to raise such particles to the higher energy
level state; (3) means for applying an electrical signal to the
amplifying device; and (4) means for securing the amplified output
therefrom, whereby the aforementioned excited particles in undergoing
a change from the higher to a lower energy state emit radiation
which is released by the applied electrical signal, thereby to amplify it.
SEE OR SEARCH CLASS:
| 250, | Radiant Energy,
subclass 251 for devices for producing and propagating a unidirectional
stream of neutral molecules or atoms through a vacuum, usually at
thermal velocity and including means to excite the molecules or
atoms at a resonant frequency. |
| 324, | Electricity: Measuring and Testing,
subclasses 300+ for electrical measuring and testing means involving nuclear
induction, which refers to operation on a nuclear resonant principle
similar to that employed in masers. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous circuits
which may utilize a maser type circuit. |
| 331, | Oscillators,
subclass 94.1 for oscillators of the molecular or particle resonant
type, e.g., maser type. |
| 332, | Modulators, appropriate subclasses for modulators of the molecular
or particle resonant type, e.g., maser type. |
| 333, | Wave Transmission Lines and Networks,
subclass 24 for gyrator type wave transmission coupling means, including
devices operating on a molecular or nuclear resonant principle similar
to that employed in masers. |
| 359, | Opticcal: Systems and Elements,
subclasses 333+ for optical or quasi-optical maser-type amplifying devices. |
|
| | |
| 4.5 | PARAMETRIC AMPLIFIERS: |
| | This subclass is indented under the class definition. Subject matter including (1) a nonlinear reactance, (2)
means for applying an input signal frequency to said nonlinear reactance,
(3) means for effectively applying a pumping frequency higher than
said signal frequency to said nonlinear reactance, and (4) means
for abstracting the amplified output therefrom, whereby sum and
difference frequencies are produced, one or both of which (but usually
the difference frequency [called the idler frequency] reacting
with the pumping frequency to produce energy at the signal frequency which
is combined in phase with the input signal.
| | (1)
Note. While the pumping frequency is higher than the signal
frequency, the pumping frequency may be derived from a lower frequency
source, for example, as a harmonic of the lower frequency source. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 7, | for an amplifier with a capacitive amplifying device. |
| 8, | for an amplifier with a saturable reactor type amplifying
device. |
| 53+, | for an amplifier with a distributed parameter coupling
means. |
|
| | |
| 4.6 | Traveling wave type: |
| | This subclass is indented under subclass 4.5. Subject matter including structure for propagating energy
of the various frequencies in interacting relationship with the
nonlinear reactance.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4, | for maser type amplifying devices. |
| 5, | for solid element wave propagating devices generally. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnections Systems,
subclass 424 for nonoptical parametric amplifier frequency converters,
per se. |
| 332, | Modulators,
subclasses 117+ or 144+ for capacitive frequency or phase modulators,
respectively, and subclass 173 for magnetic amplitude modulators. |
| 333, | Wave Transmission Lines and Networks,
subclasses 138+ , for delay networks. |
| 359, | Optical: Systems and Elements,
subclasses 326+ for parametric optical frequency translators. |
| 455, | Telecommunications,
subclasses 313+ for receivers with frequency modification or conversion
which may use parametric-type means; and subclass 336 for superrangenerative receivers. |
|
| | |
| 4.7 | Electron beam device: |
| | This subclass is indented under subclass 4.6. Subject matter wherein the propagating structure is an electron
beam device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 43+, | for travelling wave amplifiers. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 3.5+ and 39.3, for miscellaneous travelling wave tube
systems. |
|
| | |
| 4.8 | Gyromagnetic type (e.g., ferrite): |
| | This subclass is indented under subclass 4.5. Subject matter wherein the nonlinear reactance is of the
gyromagnetic type.
| | (1)
Note. The term "gyromagnetic" as applied
to material designates magnetically polarized material (e.g., ferrites, garnets,
and ionized gases) having unpaired spin systems which exhibit significant
precessional motion in an orthogonal R.F. field. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4.6, | for travelling wave type amplifiers involving gyromagnetic
nonlinear reactance. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 1.1 and 24.1+, for gyromagnetic plural channel
systems and coupling networks respectively. |
|
| | |
| 4.9 | Semiconductor type (e.g., with semiconductor diode): |
| | This subclass is indented under subclass 4.5. Subject matter wherein the nonlinear reactance is of the
semiconductor type (e.g., a diode).
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4.6, | for travelling wave type parametric amplifiers whose
nonlinear reactance is of the semiconductor type. |
| 250+, | for semiconductor amplifiers generally. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous nonlinear
circuits. |
|
| | |
| 5 | WITH SOLID ELEMENT WAVE PROPAGATING AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device comprises a
solid-state element wave propagating means having associated means, such
as a distributed parameter network, for coupling a signal wave to
be amplified to the wave propagating means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4+, | for amplifiers having amplifying devices of the
maser type including those with solid element wave propagating means. |
| 4.6, | for travelling wave type parametric amplifiers which
may utilize solid-state wave propagating means. |
| 43, | for traveling wave tube amplifiers. |
| 45, | for amplifiers having amplifier devices of the electron
beam type which include an electrode coupled to a cavity resonator. |
| 53+, | for amplifiers with distributed parameter type coupling. |
| 250+, | for amplifiers having amplifying devices of the
semiconductive type. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous circuits
which may include subject matter similar to the amplifiers classified
in this subclass. |
| 331, | Oscillators,
subclass 94.1 for oscillators of the laser type which may include
solid element wave propagating means. |
| 332, | Modulators, appropriate subclasses for modulators of the laser
type which may include solid element wave propagating means. |
| 333, | Wave Transmission Lines and Networks, appropriate subclasses, particularly
subclass 24 for distributed parameter transmission coupling means
including coupling means involving solid element wave propagating
means. |
| 372, | Coherent Light Generators, appropriate subclasses for laser type oscillators. |
|
| | |
| 5.5 | Phonon type (e.g., ultrasonic wave propagating device): |
| | This subclass is indented under subclass 5. Subject matter wherein the solid-state means is adapted
to propagate and amplify signal waves in the form of acoustic, ultrasonic
or hypersonic elastic waves of the phonon type.
SEE OR SEARCH CLASS:
| 181, | Acoustics,
subclass .5 for mechanical travelling wave structures for propagating
acoustic wave. |
| 307, | Electrical Transmission or Interconnection Systems,
subclass 424 for nonoptical parametric amplifier frequency converters
which may employ acoustic waves (e.g., Raman or Brillcuin devices). |
| 310, | Electrical Generator or Motor Structure,
subclasses 311+ piezoelectric devices in general which may propagate
elastic waves of the phonon type. |
| 333, | Wave Transmission Lines and Networks,
subclasses 138+ for wave delay networks and subclasses 187+ for
wave filters utilizing piezoelelectric wave propagating elements. |
| 359, | Optical: Systems and Elements,
subclasses 326+ for parametric optical frequency translators. |
| 367, | Communications, Electrical: Acoustic Wave Systems
and Devices, for compressional wave systems or transducers which
may employ solid element wave propagating devices of the sonic or
supersonic type. |
|
| | |
| 6 | WITH HALL EFFECT TYPE MEANS: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifier includes means for
applying or varying a magnetic field, and an electrical resistor
subjected to such field or varying field in such manner that the
value of the resistance transverse to the magnetic field changes,
thus comprising a Hall Effect Device; such Hall Effect Device may comprise
the amplifying device, per se, or may be included as a unilateralizing
means (gyrator) to insure unilateral operation of the amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 8, | for amplifiers having saturable reactor amplifying
devices. |
| 60, | for amplifiers having magnetostrictive means in
the amplifying device. |
| 62, | for amplifiers having a magnetoresistive type amplifying
device. |
| 63, | for amplifiers having a magnetic means type amplifying
device not elsewhere provided for. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 511 for miscellaneous circuits utilizing a Hall effect
type element. |
| 329, | Demodulators, appropriate subclasses for demodulators including
a Hall effect element. |
| 333, | Wave Transmission Lines and Networks,
subclass 24 for Hall effect type gyrators, and subclasses 213+ for two
terminal negative resistance networks. |
| 338, | Electrical Resistors,
subclass 32 for electrical resistors whose resistance value
changes in response to a magnetic field including resistors responding
in accordance with the Hall effect. |
|
| | |
| 7 | WITH CAPACITIVE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is a nonlinear
capacitor.
| | (1)
Note. A nonlinear capacitor is one in which for any frequency,
the ratio of the voltage across the capacitor to the current flowing
through it, is not linear. |
| | (2)
Note. To be classified in this class the output signal must
be a substantial replica of the input signal. Subject matter involving
nonlinear capacitors in which the power supply, which is controlled
by the signal, is A.C. must include filter means claimed to eliminate
the A.C. power supply from the output signal or classification
is in Class 307, Electrical Transmission or Interconnection Systems,
subclasses 40+. However subject matter involving nonlinear
capacitor amplifying devices wherein an A.C., power supply is used
and claiming a demodulator will be classified herein even where
the output filter is not claimed, if the filter is disclosed. It
will be assumed to be part of the claimed demodulator. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 8, | for amplifiers having saturable reactor type amplifying
devices. |
| 10, | for amplifiers of the modulator-demodulator type. |
| 86, | for signal feedback amplifiers with variable impedance
controlled by a separate path. |
| 95, | and 110, for signal feedback amplifiers with nonlinear
impedance means. |
| 143, | for amplifiers having a thermally responsive impedance. |
| 144+, | for amplifiers having a variable impedance for the
signal channel controlled by a separate control path. |
| 164, | for amplifiers having an electronic tube or diode
in an interstage coupling means. |
| 174, | for amplifiers having an electromechanical transducer
(e.g., piezoelectric crystal) in an interstage coupling means. |
| 183, | for amplifiers having a nonlinear device in an interstage
D.C. coupling means. |
| 250+, | for amplifiers having semiconductor type amplifying
devices, particularly subclass 287. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 401+ for nonlinear reactor systems. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 271+ and 500+ for capacitors, per se. |
|
| | |
| 8 | WITH SATURABLE REACTOR-TYPE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is a saturable
magnetic core with at least means to apply an electrical signal
and an A.C. power supply to at least one winding thereon; the input
signal which may be D.C. or A.C. is applied to the signal winding
to control an A.C. power supply applied to the power winding, which
may be the same winding or a different winding.
| | (1)
Note. To be classified in this class the signal output of
the amplifier must be a substantial replica of the input signal.
Therefore subject matter involving saturable reactors without filter
means is not classified in this class with amplifiers, but is classified
elsewhere. See the SEarch Class: notes below. Subject matter involving
saturable reactors claiming a "demodulator" and
disclosing a filter therewith but not claiming the filter are assumed
to claim the filter as part of the demodulator and are classified
herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 7, | for amplifiers having capacitive type amplifying
devices including "saturable capacitive reactor" means. |
| 10, | for modulator-demodulator type amplifiers. |
| 60, | for amplifiers having magnetostrictive means. |
| 62, | for amplifiers having magnetoresistive type amplifying
devices. |
| 63, | for amplifiers having magnetic means amplifying
devices. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 416+ for amplifiers using nonlinear reactors with a
nonlinear output signal. |
| 323, | Electricity: Power Supply or Regulation Systems,
subclasses 249 , 302, 310, and 329 for saturable inductive reactor
circuits to control voltage magnitude. See (1) Note above. |
| 336, | Inductor Devices,
subclasses 155+ for the structure of saturable inductive regulators
of the static type. |
| 361, | Electricity: Electrical Systems and Devices,
subclass 204 for saturable reactors with electric relay or electromagnet
load. |
|
| | |
| 9 | WITH PERIODIC SWITCHING INPUT-OUTPUT (E.G., FOR DRIFT CORRECTION): |
| | This subclass is indented under the class definition. Subject matter including a periodic switching means common
to the input and output circuits of the amplifier.
| | (1)
Note. This subclass includes essentially four types of subject
matter containing a periodic switch, as follows:
| | (a)
Where the signal is chopped to get A.C. which is fed to the
amplifier and the amplifier output is chopped to get a D.C. output
(this subject matter is the same as is classified in subclass 10 below
except that the modulator and demodulator are of the chopper type). |
| | (b)
The signal to the main amplifier is not chopped but a portion
to another amplifier is combined with a signal from the output of
the first amplifier and the two are chopped to get an A.C. signal
which is used to develop a corrective signal for the main amplifier. |
| | (c)
The input is compared to the output by a periodic switch to
develop a correction signal, generally for drift correction. |
| | (d)
The input and output signal are combined and then chopped
and put into the main amplifier. | |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 83, | for push-pull signal feedback amplifiers having
a D.C. feedback path. |
| 97, | for signal feedback amplifiers having a D.C. feedback
path. |
| 121, | for push-pull amplifiers having D.C. interstage
coupling. |
| 125, | for plural amplifiers having a D.C. and an A.C.
channel. |
| 159, | 161, 163, and 181+, for D.C. coupling involved
in the interstage coupling. |
| 187, | and 191, for D.C. input coupling. |
| 194, | and 198, for D.C. output coupling. |
|
| | |
| 10 | MODULATOR-DEMODULATOR-TYPE AMPLIFIER: |
| | This subclass is indented under the class definition. Subject matter including means for modulating the signal,
which is usually D.C. or low frequency A.C. amplifying means, and
means to restore the original signal, eliminating any carrier frequency
components.
| | (1)
Note. The means for eliminating the carrier need not be specifically
claimed to be classified in this class if such means are disclosed.
As for example, where a demodulator is claimed alone, and a filter
means to eliminate the carrier is disclosed the filter need not
be claimed for classification herein. The claimed demodulator will
be assumed to include the filter in such cases. |
| | (2)
Note. Where the modulator and demodulator are of the chopper
type see the search notes below. |
| | (3)
Note. Including in the "means for modulating the
signal" are chopper means to convert the signal to pulsating
direct current or alternating current. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 7, | for amplifiers having a capacitive type amplifying
device including those which modulate and demodulate the signal. |
| 8, | for amplifiers having saturable reactor type amplifying
devices including those which modulate and demodulate the signal. |
| 9, | for modulator and demodulator of the chopper type. |
SEE OR SEARCH CLASS:
| 324, | Electricity: Measuring and Testing,
subclass 118 , for measuring systems involving modulation-demodulation. |
| 329, | Demodulators, appropriate subclasses, for demodulator circuits. |
| 332, | Modulators, appropriate subclasses, for modulator circuits. |
|
| | |
| 11 | WITH D.C. REINSERTION CIRCUIT: |
| | This subclass is indented under the class definition. Subject matter including means to restore a D.C. component
to the signal, usually by means of a D.C. bias source and a rectifier
circuit supplied to the control grid.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 140, | for control of the input or gain control electrode
including a rectifier in the bias circuit. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 306+ for miscellaneous circuits with amplitude control
means. |
| 348, | Television,
subclasses 691+ for television systems including D.C. reinsertion
circuits. |
|
| | |
| 41 | WITH GAS OR VAPOR TUBE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device includes electrodes
in a gas or vapor medium and which device depends upon ionization
of a gas or vapor for its operation.
SEE OR SEARCH CLASS:
| 313, | Electric Lamp and Discharge Devices, appropriate subclasses, particularly
subclasses 161 , 163, and 567+ for gas or vapor tubes,
per se. |
| 315, | Electric Lamp and Discharge Devices: Systems, appropriate subclasses, for circuits including gas
or vapor tubes as the ultimate load device. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous electronic
tube circuits including gas or vapor tubes with a control electrode,
controlled in operation. |
|
| | |
| 42 | WITH SECONDARY ELECTRON EMISSION TUBE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is a vacuum
tube including a secondary electron emissive electrode.
SEE OR SEARCH CLASS:
| 313, | Electric Lamp and Discharge Devices,
subclasses 103+ , 377, 379, 399+, and 532+ for
vacuum tubes, per se, having secondary emissive electrode. |
| 315, | Electric Lamp and Discharge Devices, Systems
subclasses 5.11+ , 11, 12.1, 39.63 for circuits including vacuum
tubes as load devices having a secondary emissive electrode. |
|
| | |
| 43 | WITH TRAVELING WAVE-TYPE TUBE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is of the vacuum
tube type including means for generating an electron stream or beam,
and having additional means therein for propagating an electromagnetic
wave or component thereof at a velocity reduced from the free space
velocity of the wave and propagated in proximity of the electron
stream or beam, permitting exchange of energy between the electrons
and the electromagnetic wave.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 5, | for amplifiers having a solid element wave propagating
amplifying device. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices, Systems,
subclasses 3.5+ and 39.3 for traveling wave type tubes involved
as the load device in miscellaneous circuits. See the search notes under
subclasses 3.5 and 39.3. |
| 331, | Oscillators,
subclass 82 for traveling wave tube type oscillators. |
|
| | |
| 44 | WITH ELECTRON BEAM TUBE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is a vacuum
tube provided with means to form the electric space discharge into
a restricted beam or ray, usually pencil-like.
| | (1)
Note. Means to control the electron trajectory of the electrons
emitted from the cathode (as in magnetrons which are classified
below) is not regarded as an electron beam forming means required for
classification in this and indented subclasses. |
| | (2)
Note. Subject matter broadly claiming so-called "beam
power tubes" are not classified in this subclass but are
classified below in the appropriate subclass for the circuit involved. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 42, | for amplifiers having secondary electron emission
tube amplifying devices. |
| 43, | for amplifiers having traveling wave type amplifying
devices. |
| 47, | for magnetrons. |
| 308, | for amplifiers including an electron beam forming
means and a semiconductor element as a target means therein. |
SEE OR SEARCH CLASS:
| 313, | Electric Lamp and Discharge Devices,
subclasses 364+ for cathode-ray tubes, per se. See the search
notes of Class 313. |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 1+ for cathode-ray tubes with means to supply electric
current or potential thereto and/or cathode ray tubes structurally combined
with a circuit element. See the search notes of Class 315. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 600 for miscellaneous circuits having a particular
beam tube structure. |
| 329, | Demodulators, appropriate subclasses and particularly
subclass 368 for an amplitude demodulator employing an electron
discharge device of three or more electrodes. |
|
| | |
| 45 | Having electrode coupled to cavity resonator: |
| | This subclass is indented under subclass 44. Subject matter wherein at least one electrode is coupled
to a cavity resonator.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 49, | for amplifiers having vacuum tube amplifying devices
with distributed parameter characteristics. |
| 56, | for amplifiers with cavity resonator coupling means
generally. |
SEE OR SEARCH CLASS:
| 331, | Oscillators,
subclass 83 for multicavity beam tube (Klystron) oscillators. |
|
| | |
| 46 | Having deflecting means: |
| | This subclass is indented under subclass 44. Subject matter including means to deflect the electron beam.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 41, | for amplifiers having gas or vapor tube amplifying
devices including those having means to deflect the ionized gas
or vapor stream. |
| 65, | for amplifiers including vacuum tube amplifying
devices having distinctive structural characteristics or specific structural
details not elsewhere provided for in the schedule. |
SEE OR SEARCH CLASS:
| 313, | Electric Lamp and Discharge Devices,
subclasses 421+ for cathode-ray tubes, per se, having electron stream
or beam deflecting means. |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 364+ for cathode-ray tubes with means for deflecting
the cathode ray. |
|
| | |
| 47 | WITH MAGNETICALLY INFLUENCED DISCHARGE DEVICE (E.G., MAGNETRONS): |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is of the vacuum
tube type including means for magnetically influencing the electric discharge
in the device, and not provided for above.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 41, | for amplifiers having a gas or vapor type amplifying
device including those with magnetic means to deflect the ionized
stream of gas or vapor particles. |
| 42, | for amplifiers having secondary emission tube amplifying
devices including those with magnetic means. |
| 43, | for traveling wave type tube amplifiers which may
include magnetic means. |
| 44+, | for electron beam tube amplifying devices which
may include magnetic means. |
SEE OR SEARCH CLASS:
| 313, | Electric Lamp and Discharge Devices,
subclasses 153+ for discharge device combined with a magnetic device.
See the Notes and search notes of Class 313. |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 39.51+ for magnetrons. See the Notes and search Notes
and search Notes of Class 315. |
| 329, | Demodulators,
subclass 322 for a magnetron type frequency modulator and subclass
354 for a magnetron type amplitude modulator. |
| 331, | Oscillators,
subclasses 86+ for magnetron oscillators. |
|
| | |
| 49 | WITH VACUUM TUBE HAVING DISTRIBUTED PARAMETER IMPEDANCE CHARACTERISTICS: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is of the vacuum
tube type and includes within the vacuum tube an electrode or other element
having distributed parameter impedance characteristics.
| | (1)
Note. Distributed parameter characteristics as used in the
definition above include long lines and long line elements such
as lecher lines, parallel transmission lines in general, concentric
lines, wave guides, cavity resonators, tuned transmission lines,
etc., which possess distributed capacitance and inductance. For
the definition of such means, see the class definition for Class
333, Wave Transmission Lines and Networks. Inherent capacity or
inductance as for example between electrodes or of a lead inside
the tube when made use of as a lumped reactance circuit element
is classified in the appropriate subclass involving the circuit;
neutralization by feedback is classified in subclasses 76+ below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4, | for amplifiers having a maser type amplifying device
which may include distributed parameter impedance structure. |
| 5, | for amplifiers having a solid element wave propagating
amplifier device. |
| 43, | for amplifiers including traveling wave tubes. |
| 45, | for amplifiers of the type having an electron beam
tube amplifying device with an electrode coupled to a cavity resonator. |
| 53+, | for amplifiers with distributed parameter type coupling.
See the search notes thereunder. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 39+ for a vacuum tube combined with distributed parameter
type transmission means structure, with the tube as the load device.
See the notes and search notes thereunder. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 593 for miscellaneous circuits with distributed parameters. |
| 359, | Optical: Systems and Elements,
subclasses 333+ for laser amplifiers. |
|
| | |
| 50 | WITH DUMMY TUBE: |
| | This subclass is indented under the class definition. Subject matter including in addition to the amplifying device
of the vacuum tube type, a similar vacuum tube, with the cathode unheated,
so that the additional tube does not serve as an active element
but merely presents impedance relations in the circuit similar to those
of the amplifying device vacuum tube, usually for neutralizing the
effects of the amplifying device interelectrode impedances.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 76+, | for amplifiers having signal feedback means to compensate
for inter-electrode impedance. See the notes and search notes thereunder. |
|
| | |
| 51 | COMBINED WITH AUTOMATIC AMPLIFIER DISABLING SWITCH MEANS: |
| | This subclass is indented under the class definition. Subject matter combined with switch means, which may be
of the electromechanical or electronic tube type (vacuum, gas, or
vapor tubes), to disable or discontinue the operation of the amplifier
automatically in response to a predetermined condition.
| | (1)
Note. Miscellaneous gating circuits are classified in Class
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits,
and Systems, subclasses 365+ unless significant details
of an amplifier as classified in the class definition of this class
are claimed when classification is in this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 65+, | for specific structure involved in the amplifier
including structure involving switching means. |
| 127+, | for amplifiers having means to control power supply
or bias voltage. |
SEE OR SEARCH CLASS:
| 200, | Electricity: Circuit Makers and Breakers, appropriate subclasses, for switches, per se. |
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 112+ for electrical transmission or interconnection
switching systems. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 365+ for miscellaneous gating circuits. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 1+ for electrical systems and devices with safety
and protection means including those involving disabling switching
means; subclasses 139+ for circuits for electric relays. |
|
| | |
| 52 | WITH PILOT FREQUENCY CONTROL MEANS: |
| | This subclass is indented under the class definition. Subject matter including means for control of the amplifier
which may be for control of the bias of an amplifier device electrode
or of a variable impedance for the signal channel, wherein the signal
input includes a component of a particular frequency not involved
in the signal for signal purpose, which is selected by a means in
or associated with the amplifier and applied to the control means
or used to develop a control voltage applied to the control means.
| | (1)
Note. See the class definition, Lines With Other Classes
and Within This Class, for other systems utilizing pilot frequency
control. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 85, | for signal feedback amplifiers having an amplifier
in the feedback path. |
| 86, | for signal feedback amplifiers having a variable
impedance in the feedback path controlled by a separate control path. |
| 96, | for signal feedback amplifiers combined with control
of bias of the signal amplifier. |
| 127+, | appropriate subclasses, for control of bias or power
supply, particularly subclasses 130 and 132. See the search notes
under subclass 127. See also (2) Note under subclass 130. |
| 143, | for amplifiers having a thermally responsive impedance
which may be controlled by a separate means. |
| 144+, | for amplifiers having a variable impedance which
may be controlled by a separate control path. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks, appropriate subclasses for pilot current controlled
transmission line systems, generally. See the note and search notes. |
| 370, | Multiplex Communications,
subclasses 491 and 500 for a multiplexing system using pilot control. |
|
| | |
| 53 | WITH DISTRIBUTED PARAMETER-TYPE COUPLING MEANS: |
| | This subclass is indented under the class definition. Subject matter wherein the signal energy is coupled to or
from the amplifying device by means including distributed parameter
wave transmission means; or circuit networks of lumped parameters
or impedances designed to simulate the impedance characteristics
of distributed parameter wave transmission means.
| | (1)
Note. Distributed parameter transmission means as used in
the definition above include long lines and long line elements such
as telephone and telegraph lines, lecher lines, parallel transmission
lines, in general, concentric lines, wave guides, cavity resonators, tuned
transmission lines, etc., which possess distributed capacitance
and inductance. For the definition of such means and "lumped
parameter or impedance" means as used above, see the class
definition for Class 333, Wave Transmission Lines and Networks.
Subject matter involving inherent capacity or inductance, as for
example, between electrodes, or of a lead inside a tube when made
use of as a lumped reactance circuit element, is classified in the
appropriate subclass involving the circuit. Neutralization by feedback
is classified in subclasses 76+ below. |
| | (2)
Note. Subject matter including distributed parameter circuit
coupling means when combined with a special type of amplifying device
is classified with the special type of device and not in this subclass.
For example, subclass 43, for amplifiers having traveling wave
type tubes, which include distributed parameter type delay lines,
or wave guides. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for amplifiers having plural diverse type amplifying
devices. |
| 4, | for amplifiers having a maser type amplifying device. |
| 5, | for amplifiers which have solid element wave propagating
amplifying devices. |
| 43, | for amplifiers having a traveling wave type tube
amplifying device. |
| 45, | for electron beam tube amplifying devices coupled
to a cavity resonator. |
| 49, | for amplifiers having an amplifying device of the
vacuum tube type having distributed parameter characteristics. |
| 107, | for signal feedback amplifiers having phase shift
means in the loop path. |
| 157+, | for amplifier interstage coupling. |
| 185+, | for amplifier input coupling. |
| 192+, | for amplifier output coupling. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems, appropriate subclasses indented under
subclass 3 and subclass 39 for distributed parameter impedance
devices. |
| 333, | Wave Transmission Lines and Networks, appropriate subclasses for passive distributed impedance
devices. See the notes under the class definitions and search notes
under the pertinent subclasses of Class 333. |
|
| | |
| 54 | Distributed amplifier: |
| | This subclass is indented under subclass 53. Subject matter wherein a plurality of amplifier devices
are in a system having a single source and load, include a delay
line coupling (which may be a distributed parameter line, or an
artificial line) and wherein the inputs or outputs of such amplifier
devices are coupled to such delay line means at phase displaced
points.
| | (1)
Note. Push-pull amplifiers including delay line coupling,
per se, are not classified in this subclass but in subclass 55 below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 124+, | for plural channel amplifiers. See the notes and
search notes thereunder. |
|
| | |
| 55 | Push-pull: |
| | This subclass is indented under subclass 53. Subject matter including at least one push-pull stage of
amplification.
| | (1)
Note. A push-pull stage of amplification for this class requires
a balanced input to two tubes and a balanced output therefrom; for
further details of the definition of a push-pull stage of amplification
see the class definitions of this class, section I. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 118+, | for push-pull amplifiers generally. See the notes
and search notes thereunder. |
|
| | |
| 56 | Waveguide, cavity, or concentric line resonator: |
| | This subclass is indented under subclass 53. Subject matter wherein the distributed parameter wave transmission
means is of the wave guide, cavity concentric line type and is resonant.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 45, | for electron beam tube amplifying device coupled
to a cavity resonator. |
| 94, | and 109, for signal feedback amplifiers having frequency
responsive means in the feedback path. |
| 302+, | for semiconductor amplifiers having frequency responsive
in the signal transmission path. |
SEE OR SEARCH CLASS:
| 331, | Oscillators,
subclass 83 for multicavity beam tube oscillators (Klystrons). |
| 333, | Wave Transmission Lines and Networks,
subclasses 219+ for distributed parameter type resonators. See the
note and search notes to this subclass. |
|
| | |
| 57 | Artificial line: |
| | This subclass is indented under subclass 53. Subject matter wherein there is included as a signal coupling
means a circuit network of lumped parameters or impedances, which
is designed to simulate the impedance characteristics of a distributed
parameter wave transmission means.
| | (1)
Note. Distributed parameter transmission means as used in
the definition above include long lines and long line elements such
as telephone and telegraph lines, lecher lines, parallel transmission
lines, in general, concentric lines, wave guides, cavity resonators, tuned
transmission lines, etc.., which possess distributed capacitance
and inductance. For the definition of such means and "lumped
parameter or impedance" means as used above, see the class definition
for Class 333, Wave Transmission Lines and Networks. Subject matter
involving inherent capacity or inductance, as for example, between electrodes,
or of a lead inside a tube when made use of as a lumped reactance circuit
element, is classified in the appropriate subclass involving the
circuit. Neutralization by feedback is classified in subclasses
76+ below. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclass 23 , for passive type artificial line, per se; and
subclasses 138+, for delay lines. |
|
| | |
| 58 | WITH ROTATING DYNAMOELECTRIC AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is provided
with a rotating dynamoelectric means; and wherein the power supply
electrical energy source which is controlled, may be developed by
conversion of mechanical energy to electrical energy by the motion
of the armature of the dynamoelectric means, the signal current
being applied to magnetic field means of the device, so that a current
is generated which varies with the signal current supplied; or the
rotating dynamoelectric means may act as a motor with the signal
current applied to the rotating means or the field means, and the
rotary motion of the device may be utilized as a variable resistor
means to effect a control of the power supply source.
| | (1)
Note. Subject matter, as defined above, is classified herein
where the device is disclosed as designed to amplify a signal.
Where the system is primarily for the conversion of electrical energy
into mechanical energy or vice versa, or is of general utility,
classification is in Class 310, Electrical Generator or Motor Structure,
or Class 322, Electricity: Single Generator Systems, as described
in the, SEARCH CLASS, below. Where the structure of a dynamoelectric machine
is claimed, alone, classification is in the appropriate subclass
of Class 310, Electrical Generator or Motor Structure. |
SEE OR SEARCH CLASS:
| 310, | Electrical Generator or Motor Structure,
subclasses 10+ and subclasses indented thereunder for the structure of
dynamoelectric machines, per se, especially indented subclasses
139 and 151 for the structure of generators of the rotary amplifier
type. |
| 322, | Electricity: Single Generator Systems, appropriate subclasses particularly
subclass 61 for generators with alternating current excitation
and subclasses 90 and 91+ for rotating amplifiers, especially
indented subclass 92 for such amplifiers of the crossed-field type. |
|
| | |
| 59 | HAVING LIGHT-CONTROLLED OR ACTIVATED DEVICE (I.E., NOT
LIGHT SIGNAL): |
| | This subclass is indented under the class definition. Subject matter including means controlled by light or activated
by light which may be involved in the amplifying device, per se, used
as a control means, or which may be included in any other part of
the amplifier.
| | (1)
Note. Subject matter wherein light controlled or activated
means is not a part of the amplifier but is combined therewith (as
for example, as a photo-electric cell with light means therein feeding
a signal current to a vacuum tube amplifier) is not classified in
this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 308, | for amplifiers having atomic particle or radiant
energy impinging on a semiconductor amplifying device. See the
search notes thereunder. |
SEE OR SEARCH CLASS:
| 250, | Radiant Energy,
subclasses 200+ , appropriate subclasses for photocell circuits.
See also the notes and search notes under subclass 200. |
|
| | |
| 60 | HAVING MAGNETOSTRICTIVE-TYPE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device includes magnetostrictive
means, that is, means for cyclically changing the dimensions of
a body of magnetic material under the influence of a cyclically
changing magnetic field in proximity to the body of magnetic material.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 174, | for interstage coupling including electromechanical
transducer means (e.g., piezoelectric crystals). See the search notes
thereunder. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 148+ and 186+ for electromechanical transducer
delay lines and filters, respectively. See the search notes thereunder. |
| 336, | Inductor Devices,
subclass 20 for inductive devices having magnetostrictive (deformable)
cores. |
|
| | |
| 61 | WITH RESISTIVE-TYPE AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device, to which the
electric input signal is applied to control the power supply source
of electric energy also applied thereto, is a resistive means, which
may be liquid, solid, or of granular construction.
| | (1)
Note. Not included herein, are other devices having resistive
properties such as gas tubes, vacuum tubes, etc. |
| | (2)
Note. Variable resistors, although including a sensing means
and/or power supply means, as structure are classified in
Class 338, Electrical Resistors. Where such subject matter involves
a load circuit, classification is herein, when the signal output
is "substantially a replica of the signal input";
otherwise classification is in the appropriate subclass of Class
323, Electricity: Power Supply or Regulation Systems. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 250+, | for amplifiers with semiconductor type amplifying
devices. See the notes and search notes thereunder. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for systems utilizing variable
resistance devices of the nonlinear conductor type and which systems
are not elsewhere classifiable. |
| 338, | Electrical Resistors, appropriate subclasses for the structure of resistors, per
se, especially
subclass 100 . See (1) Note above. |
|
| | |
| 62 | Magnetoresistive type: |
| | This subclass is indented under subclass 61. Subject matter wherein the amplifying device resistive means
is of a type whose resistance value varies in response to a magnetic
field or a change in magnetic field, and includes means for applying
such magnetic field to the resistive means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 6, | for amplifiers having Hall Effect type amplifying
devices. |
| 60, | for amplifiers having magnetostrictive means. |
| 63, | for amplifiers having an amplifying device with
magnetic means, generally. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 511 for miscellaneous circuits using the Hall effect. |
| 338, | Electrical Resistors,
subclass 32 for electrical resistors whose resistance value
changes in response to a magnetic field or a change in magnetic field. |
|
| | |
| 63 | WITH MAGNETIC MEANS AMPLIFYING DEVICE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device includes a
magnetic means to control the power supply energy or is involved
in the structure of the amplifying device in some other manner and
which is not provided for above.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 6, | for amplifiers including Hall effect type amplifying
devices. |
| 41, | for amplifiers including gaseous or vapor type amplifying
devices which may have magnetic means for deflection or other purposes. |
| 44+, | for amplifiers having electron beam tube amplifying
devices which may have magnetic means for beam deflection, focusing
or other purposes. |
| 47+, | for amplifiers having magnetically influenced discharge
devices including magnetrons. |
| 60, | for amplifiers having magnetostrictive means. |
| 62, | for amplifiers having magnetoresistive type amplifying
devices. |
|
| | |
| 64 | WITH SPACE CHARGE GRID TUBE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifying device is of the vacuum
tube type having a positively charged grid (with respect to the
cathode) immediately adjacent the cathode, which neutralizes the
negative space charge of the electrons emitted from the cathode
so that a "virtual cathode" is produced on the
side of the space charge grid on which the anode is situated, said
tube having a normally negatively biased control grid next to the
space charge grid, to which the signal is coupled, and an anode
to receive the electrons emitted by the cathode, and which may have
additional electrodes between the control grid and the anode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 65, | for amplifiers including vacuum tubes of special
structural characteristics. |
| 199+, | for power or bias voltage supply for amplifiers,
see the search notes thereunder. |
SEE OR SEARCH CLASS:
| 313, | Electric Lamp and Discharge Devices, appropriate subclasses, for discharge device structure,
per se. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 524+ for miscellaneous electron tube circuits with space charge
grid tubes. |
| 329, | Demodulators,
subclass 368 for an amplitude demodulator using an electron
discharge device of three or more electrodes. |
|
| | |
| 65 | INVOLVING STRUCTURE OTHER THAN THAT OF TRANSFORMERS PER SE: |
| | This subclass is indented under the class definition. Subject matter involving the structure of any amplifier
circuit element, such as resistors, vacuum tubes, etc., with the
exception of the structure of transformer elements, or of the structural
relationships of such elements in the amplifier.
| | (1)
Note. The term structure, herein, refers to the arrangement
in space of the parts to the whole of the circuit element or of the
elements comprising the amplifier which includes also the material
of which such parts are constructed. The term structure is distinguished
from circuit or circuit arrangement in that the latter refers to
an abstract schematic of parts identified broadly by their function in
the circuit and arranged according to the sequence of signal current
flow and not according to actual arrangement in space, or construction. |
| | (2)
Note. Subject matter involving the structure of transformers
is not classified in this or indented subclasses but in subclasses
171, 190, or 197 below. |
| | (3)
Note. Subject matter involving the structure of any amplifying
device or associated therewith, of the types specifically provided
for above are not classified in this or indented subclasses but
in the appropriate subclasses for those types, above. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers having distributed parameter coupling
means including the structure of such distributed parameter means. |
SEE OR SEARCH CLASS:
| 174, | Electricity: Conductors and Insulators, for the structure of electrical insulators and conductors. |
| 200, | Electricity: Circuit Makers and Breakers, for the structure of switches and circuit breakers. |
| 313, | Electric Lamp and Discharge Devices, appropriate subclasses for the structure of electric
discharge devices (vacuum tubes and gas tubes), per se. |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 3+ for combined cathode-ray tube and circuit element
structure, subclasses 32+ for vacuum or gas tubes combined
with integral circuit structure or temperature modifying means structure
where the tube is the load device. |
| 334, | Tuners, appropriate subclasses for tuners, per se. |
| 336, | Inductor Devices, appropriate subclasses for inductor structure. |
| 338, | Electrical Resistors, for the structure of resistors and rheostats. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 271+ for capacitor structure, subclasses 600+ for housing
and mounting assemblies with plural diverse electrical components,
subclass 679.01 for electronic systems and devices, subclasses 679.02-679.61
for computer related housing or mounting assemblies, and subclasses
500+ for electrolytic capacitors. |
| 439, | Electrical Connectors, appropriate subclasses for the structure of electrical
connectors. |
| 455, | Telecommunications,
subclasses 130+ for radio receiver structure in general; and subclass
351 for portable radio receivers. |
|
| | |
| 66 | With printed circuits: |
| | This subclass is indented under subclass 65. Subject matter wherein the capacitive electrode structure,
inductor structure, resistors, conductors, connectors and/or
related circuit elements form a conductive coating on a base. For example,
such as is produced by printing, spraying, electro-deposition or
similar coating method, or by the removal of adherent conducting
material from an insulating base by etching, grinding, or the like.
SEE OR SEARCH CLASS:
| 174, | Electricity: Conductors and Insulators,
subclasses 250+ for preformed panel circuit arrangement (e.g., printed
circuits). |
| 336, | Inductor Devices,
subclass 200 for inductor coil structure of the printed circuit
type. See the search notes thereunder. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 736+ and 748+ for printed circuits of the type
used in radios. |
| 439, | Electrical Connectors,
subclasses 55+ for connectors of the preformed panel circuit (e.g.,
printed circuit) type. |
|
| | |
| 67 | With capacitive structure: |
| | This subclass is indented under subclass 65. Subject matter wherein the structure involved is that of
a capacitor or capacitive element of the amplifier circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 157+, | appropriate subclasses thereunder for interstage
coupling circuits involving capacitors. |
| 185+, | appropriate subclasses for input coupling circuits
involving capacitors. |
| 192+, | appropriate subclasses for output coupling circuits
involving capacitors. |
SEE OR SEARCH CLASS:
| 334, | Tuners, appropriate subclasses for tuned networks for use
in wave energy apparatus and comprising inductance and capacitance
elements in circuit arrangement to form a resonant circuit and in
which structure is provided for adjusting one or both of these elements
for changing the mean resonant frequency of the circuit. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 271+ and 503+ for capacitor structure, per
se. |
|
| | |
| 68 | With shielding means: |
| | This subclass is indented under subclass 65. Subject matter wherein the structure is some means for shielding
at least part of the amplifier from external electric or magnetic
fields, or such structure to protect parts of the device from undesired
electric or magnetic fields originating in another part of the device,
or such structure to prevent the amplifier or a part thereof from
emanating undesired electric or magnetic fields.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 170, | for shielding involved in interstage transformers. |
| 190, | for shielding involved in input transformers. |
| 197, | for shielding involved in output transformers. |
SEE OR SEARCH CLASS:
| 174, | Electricity: Conductors and Insulators,
subclasses 32 through 397for miscellaneous anti-inductive structures, particularly
subclasses 350-397 for miscellaneous electrical shields and screen
structures not elsewhere classifiable. The search notes to subclasses
32-397 indicate further fields of search for anti-inductive and shielding
structures. |
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 89+ for anti-inductive means to prevent or modify the
coupling between electrical systems, particularly subclass 91, for "shielding
means". See the search notes thereunder. |
| 333, | Wave Transmission Lines and Networks,
subclass 12 for transmission line inductive or radiation interference reduction
systems which include shielding means for the purpose. See the
search notes thereunder. |
| 334, | Tuners,
subclass 85 for a tuner having shielding or housing means. |
|
| | |
| 69 | SUM AND DIFFERENCE AMPLIFIERS: |
| | This subclass is indented under the class definition. Subject matter including at least two sources of signal
voltage which are combined in the amplifier so that the signal output
of the amplifier is a linear function of the sum or difference of
the signal input sources.
| | (1)
Note. Balanced input circuits or balanced output circuits
are considered single signal sources or loads in this class. Therefore
a balanced to unbalanced amplifier is not classified in this subclass but
in subclass 116 below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 74, | for series energized vacuum tube amplifiers with
plural separate signal inputs. |
| 81, | for signal feedback amplifiers having at least one
push-pull stage. |
| 116, | for amplifiers having balanced-to-unbalanced coupling.
See (1) Note above. |
| 118+, | for amplifiers including a push-pull stage. |
| 124+, | for amplifiers with plural amplifier channels. |
| 147, | for amplifiers having plural signal inputs. See
the notes and search notes thereunder. |
| 252+, | and 295, for semiconductor amplifiers having plural
channels or plural inputs. |
| 301, | for semiconductor amplifiers having balanced-to-unbalanced
or unbalanced-to-balanced coupling. |
|
| | |
| 70 | ANODE ENERGIZED THROUGH DISCHARGE PATH OF CONTROLLED VACUUM
TUBE: |
| | This subclass is indented under the class definition. Subject matter including at least two amplifying devices
of the vacuum tube type, each having at least three electrodes including a
control grid electrode, wherein at least a portion of the anode-cathode
power supply current, for one of the amplifying devices, flows in series
from the power supply source through the space discharge path of
the other amplifying device, so that the tubes are series energized
(at least in part) from the power supply.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 87+, | for cathode impedance feedback, particularly subclass
95. |
| 128, | for control means for the anode circuit including
diode space discharge paths in such circuits. |
| 202, | for anode power supply, generally. See the search
notes thereunder. |
| 293, | and 310+, for cascaded semiconductor amplifiers
series energized for power. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 530+ for miscellaneous electron tube circuits with a
particular source of power or bias voltage. |
| 329, | Demodulators, appropriate subclasses for a demodulator with particular
power supply circuitry. |
|
| | |
| 71 | Plural discharge paths traversed by anode supply: |
| | This subclass is indented under subclass 70. Subject matter wherein power supply current for one or more
vacuum tube amplifying devices is supplied through at least two
separate space discharge paths of at least two vacuum tubes.
| | (1)
Note. Subject matter including separate and distinct groups
of pairs of vacuum tubes having separate and distinct series energized
space discharge paths is also included in this subclass. |
| | (2)
Note. A series of three or more vacuum tubes arranged in
series for power supply which comprises a single discharge path for
the anode power supply is excluded from this subclass. | |
| | |
| 72 | Amplifier devices in arms of a bridge: |
| | This subclass is indented under subclass 71. Subject matter including two pairs of series energized tubes
wherein one tube of each pair is supplied through its space discharge
path with anode-cathode power supply current from the power supply
source, and wherein each of the four vacuum tubes is arranged in
the arms of a Wheatstone bridge. |
| | |
| 73 | Plural outputs: |
| | This subclass is indented under subclass 70. Subject matter including at least two separate signal output
circuits.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 148, | for signal amplifiers having plural separate signal
outputs. See the notes and search notes thereunder. |
|
| | |
| 74 | Separate signal inputs to series devices: |
| | This subclass is indented under subclass 70. Subject matter including at least two separate input circuits
for each of two series energized vacuum tube amplifying devices.
| | (1)
Note. A balanced (or push-pull) input circuit is treated
as a single input circuit in this class and not as two separate
input circuits. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 69, | for sum and difference amplifiers. |
| 147, | for amplifiers with plural signal inputs. See the
notes and search notes thereunder. |
|
| | |
| 75 | SIGNAL FEEDBACK: |
| | This subclass is indented under the class definition. Subject matter wherein signal feedback circuit means are
provided to superimpose a portion of the electrical signal output
energy on the amplifier input signal.
| | (1)
Note. The above amplifier may be any stage or group of stages
of a cascaded amplifier. |
| | (2)
Note. The signal feedback of amplifiers classified in this
and indented subclasses is distinguished from the type of feedback
which may be found in amplifier gain control circuits principally
in subclasses 129+ in that the latter involves the development
from the signal, of a D.C. voltage which is filtered and smoothed
and then applied to an amplifier electrode to control the bias thereon; whereas
in this and indented subclasses the feedback voltage which is applied
to the input electrode varies in each instant in the same manner
that the signal varies and may be in any phase relationship with
the input signal (i.e., in phase, 180° out of phase or
any other phase angle relationship). |
| | (3)
Note. The term "loop path" as used in some
of the indented subclasses refers to the loop formed by the forward
signal path from the signal input electrode in the circuit to which
the signal feedback is applied to the output and in addition the
signal feedback path from the signal output electrode from which
the feedback is derived to the signal input electrode to which the
signal feedback is applied. |
| | (4)
Note. In feedback amplifiers there is an impedance shared
by the input and output circuits which may be a transformer. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 291+, | for semiconductor amplifiers having signal feedback. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 590 for miscellaneous circuits with signal feedback. |
| 329, | Demodulators,
subclass 319 for feedback used in frequency demodulation noise
reduction, and subclass 367 for regenerative feedback in an amplitude demodulator. |
| 331, | Oscillators, appropriate subclasses, for oscillator circuits
utilizing feedback. |
| 700, | Data Processing: Generic Control Systems or Specific
Applications, appropriate subclasses for data processing control systems,
particularly
subclasses 1 through 89for closed loop feedback systems. |
|
| | |
| 76 | Compensating for inter-electrode impedance (e.g., neutralization): |
| | This subclass is indented under subclass 75. Subject matter wherein the "signal feedback circuit
means" are provided from compensating for or nullifying
the undesirable feedback caused by any inter-electrode impedances
of a vacuum tube amplifying device.
| | (1)
Note. The undesirable feedback effects are usually caused
by capacitive inter-electrode impedance although the inter-electrode
impedance involved may be inductive or conductive (e.g., resistive). |
| | (2)
Note. Neutralization of the effects of inter-electrode impedances
by other than feedback means is not specifically provided for in
this and indented subclasses but is classified with the specific
circuit means involved, as for example, in input or output coupling,
(subclasses 185+ and 192+, respectively). Where
the inter-electrode impedance is made use of, as for example, where
the input (grid-cathode) capacitance is part of the tuned input
circuit classification is in the appropriate subclass considering
the inter-electrode capacitance as though it were a conventional
external circuit element. |
| | (3)
Note. Grounded grid amplifiers which inherently mitigate
the effects of inter-electrode capacitances in vacuum tubes are
classified in the cathode coupled subclasses for which see subclasses
186 and 193 and the search notes thereunder. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 50, | for amplifiers having a dummy tube. |
| 65+, | for the structure of elements of the amplifier circuit
including vacuum tubes but excluding transformers, per se. |
| 292, | for semiconductor amplifiers involving compensating
feedback for inter-electrode impedance (e.g., neutralization). |
SEE OR SEARCH CLASS:
| 329, | Demodulators,
subclass 319 for feedback used in frequency demodulation noise
reduction, and subclass 367 for regenerative feedback in an amplitude demodulator. |
| 331, | Oscillators,
subclasses 175+ for oscillator systems wherein the inter-electrode
impedance of the active element of the oscillator may be compensated for
stabilizing the frequency of the generated oscillations. |
|
| | |
| 77 | At least one push-pull stage: |
| | This subclass is indented under subclass 76. Subject matter including at least one push-pull stage of
signal amplification.
| | (1)
Note. For the definition of a push-pull stage of amplification
see the class definitions, section I. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 81+, | for feedback amplifiers having at least one push-pull
stage. See the search notes thereunder. |
| 118+, | for amplifiers including a push-pull stage. See
search notes thereunder. See also (1) Note above. |
|
| | |
| 78 | To or from electrode common to input and output: |
| | This subclass is indented under subclass 76. Subject matter wherein the feedback for nullifying or mitigating
the effects of inter-electrode impedance is applied to or from an electrode
common to the input and output circuits of an amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 87+, | for cathode impedance feedback. (See the search
notes thereunder). |
| 111, | for signal feedback to or from an auxiliary grid
or to the anode. See the search notes thereunder. |
|
| | |
| 79 | By transformer feedback: |
| | This subclass is indented under subclass 76. Subject matter wherein the signal feedback for compensating
for inter-electrode impedance is coupled back to the input from
the output by means of a transformer.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 165+, | for amplifiers having interstage transformer coupling.
See the search notes thereunder. |
| 188+, | for amplifier input transformer coupled circuits.
See search notes thereunder. |
| 195+, | for amplifier output transformer coupled networks.
See search notes thereunder. |
|
| | |
| 80 | By coil in parallel to and resonating with inter-electrode
capacity: |
| | This subclass is indented under subclass 76. Subject matter wherein an inter-electrode capacitance which
may be between the grid and cathode or anode and grid is compensated for
by a feedback circuit including an inductance in parallel with such
inter-electrode capacitance (in the feedback path) and resonant therewith.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 109, | for amplifiers having frequency responsive feedback
means. |
|
| | |
| 81 | At least one push-pull signal stage: |
| | This subclass is indented under subclass 75. Subject matter including at least one stage of push-pull
signal amplification.
| | (1)
Note. For the definition of a stage of push-pull amplification
see the class definition, Glossary. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 77, | for amplifiers having at least one push-pull stage
and including feedback means to compensate for inter-electrode impedances. |
| 118, | for amplifiers having at least one push-pull stage.
See the search notes thereunder. See also (1) Note above. |
|
| | |
| 82 | Positive and negative feedback: |
| | This subclass is indented under subclass 81. Subject matter including at least one signal feedback means
wherein the signal feedback at the amplifier device input means
has a component in phase with the input signal at this point in
the circuit, and at least one signal feedback means wherein the
signal feedback at the amplifier device input means has a component opposite
in phase with the input signal at the amplifier input to which such
feedback is applied.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 89, | for cathode-cathode feedback for cascaded adjacent
amplifier stages. |
| 93, | for combined diverse type feedback coupling including
positive feedback. |
| 101, | for positive and negative in the same path at different
frequencies. |
| 104, | for positive and negative feedback generally. |
|
| | |
| 83 | Including D.C. path for signal feedback: |
| | This subclass is indented under subclass 81. Subject matter wherein the signal feedback path from the
output electrode of the amplifier device from which the signal feedback
is derived to the input electrode of the amplifying device to which
the signal feedback is applied has a D.C. conductive path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching input-output
comparison including those with D.C. conductive feedback paths. |
| 97, | for amplifiers having a D.C. conductive signal feedback
path. |
|
| | |
| 84 | Plural amplifier channels: |
| | This subclass is indented under subclass 75. Subject matter involving plural amplifier channels combined
in addition, for one or more channels, with signal feedback means
above.
| | (1)
Note. Subject matter wherein the signal feedback is derived
from the signal output of one amplifier signal channel and applied
to the signal input of another amplifier signal channel, is classified
in this subclass. |
| | (2)
Note. For the definition of plural amplifier channels see
subclass 124 below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 124+, | for amplifiers with plural amplifier channels.
See the notes and search notes thereunder. |
|
| | |
| 85 | Amplifier in signal feedback path: |
| | This subclass is indented under subclass 75. Subject matter wherein the "signal feedback circuit
means" has an amplifier therein, as defined in the class
definition, which may have bias control means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 86, | for amplifiers having a variable impedance in a
signal feedback path varied by a separate control path. |
| 96, | for amplifiers having signal feedback combined with
means to control the bias of an electrode in the signal amplifier. |
| 129+, | for amplifiers having control of the input electrode
or gain control electrode bias. See the search notes thereunder. |
| 144+, | for amplifiers having a variable impedance for the
signal channel controlled by a separate control path. See the search
notes thereunder. |
SEE OR SEARCH CLASS:
| 329, | Demodulators,
subclass 319 for feedback used in frequency demodulation noise
reduction, and subclass 367 for regenerative feedback in an amplitude demodulator. |
|
| | |
| 86 | Variable impedance in feedback path varied by separate
control path: |
| | This subclass is indented under subclass 75. Subject matter wherein the "signal feedback circuit
means" has a variable impedance therein, which is varied
by means of a control which may be a variable control voltage or
a motor control means, the control to vary the variable impedance
being derived, developed and applied by a path separate from that involving
the variable impedance and the immediately associated signal transmission path.
| | (1)
Note. This subclass excludes "nonlinear" or
other impedances in the signal feedback path which vary merely by
the signal feedback current flow therethrough and which are not
provided with a "separate" means to control the
variable impedance. Such subject matter is classified in subclasses
95 and 110 of this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 143, | for amplifiers having a thermally responsive impedance
which may be separately controlled. |
| 144+, | for amplifiers having a variable impedance for the
signal channel varied by a separate control path. See the search
notes thereunder. |
|
| | |
| 87 | Cathode impedance feedback: |
| | This subclass is indented under subclass 75. Subject matter wherein the "signal feedback circuit
means" or the "shared impedance of the input and
output circuits" or a portion thereof is an impedance between
the cathode of a vacuum tube amplifying device and ground or other
convenient electrical potential reference plane.
| | (1)
Note. For this and indented subclasses the anode current
flowing through the "cathode impedance" develops
a variable signal potential on the cathode which, relative to the
grid of the same amplifying device is effective as a negative signal
feedback in that amplifying device; and which may in addition be applied
as a signal feedback from such cathode impedance to another input
electrode of the same amplifying device (or an amplifying device
of a preceding stage); or to which cathode impedance a signal feedback
may be applied from an output electrode of the same amplifying stage
or a following signal amplifying stage. |
| | (2)
Note. Subject matter involving cathode coupling, such as
cathode follower output circuits or where coupling is to the cathode
and there is normally no cathode impedance signal feedback as in "bootstrap" coupling
(subclass 156, below) or where no signal feedback function is indicated,
is not classified in this and indented subclasses but in the appropriate
cathode coupling subclasses below such as subclasses 186+,
for input circuit network coupling to the cathode and subclasses
193+, for output circuit coupling from the cathode. See
the internal search notes under these subclasses for other subclasses
of this class involving cathode coupling. |
| | (3)
Note. The above requirement of (2) Note, for classification
in this and indented subclasses, namely, that where cathode coupling
is involved an indication that signal feedback is present in the circuit,
applies to all of these subclasses except subclass 89 involving
cathode impedance feedback between adjacent stages. Where there
is cathode-to-cathode coupling of adjacent cascaded stages classification
is in subclass 89 regardless of whether signal feedback is indicated or
not. |
| | (4)
Note. Subject matter involving a cathode impedance which
does not develop a signal feedback voltage but is by-passed in such
manner that a D.C.. bias voltage is developed, or due to operating
conditions, is disclosed, in the case of a single by-passed resistor,
as developing a D.C. bias there across and not a voltage varying
with the signal, are not classified in this and indented subclasses
but in subclass 142 below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for vacuum tube amplifying device amplifiers series
energized for power. |
| 78, | for signal feedback circuits compensating for inter-electrode
impedances to or from a common electrode. |
| 119, | for push-pull amplifiers involving cathode coupling. |
| 158+, | for interstage coupling to the cathode. |
| 168, | for transformer interstage coupling from the cathode. |
| 172+, | for interstage coupling from the cathode. |
| 186+, | for input coupling to the cathode. |
| 193+, | for output coupling from the cathode. |
| 291+, | for semiconductor amplifiers having signal feedback
means. |
| 297, | for semiconductor amplifiers series energized for
power. |
|
| | |
| 88 | Cascade amplifier stages with cathode-cathode feedback: |
| | This subclass is indented under subclass 87. Subject matter involving at least two stages of amplification
wherein the output of each stage is coupled to the input of the
preceding stage except the first, and wherein at least two of the stages
are arranged as defined in subclass 87 with signal feedback from
the cathode impedance of the latter of the cascaded stages to the cathode
impedance of a preceding stage.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 92, | for signal feedback to the cathode impedance of
a prior stage combined with diverse type signal feedback. |
| 98+, | for signal feedback in cascaded amplifiers generally. |
|
| | |
| 89 | Between adjacent stages: |
| | This subclass is indented under subclass 88. Subject matter wherein the cathode-cathode feedback is between
adjacent stages.
| | (1)
Note. Where there is cathode-to-cathode coupling of adjacent
cascaded stages classification is in subclass 89 regardless of whether
signal feedback is indicated or not. | |
| | |
| 91 | Diverse feedback to or from cathode: |
| | This subclass is indented under subclass 90. Subject matter wherein the diverse signal feedback is derived
from the cathode feedback impedance and fed to the input electrode
of the same or a prior stage; or wherein the diverse signal feedback
is derived from an output electrode of the same or a following stage
and applied to the cathode impedance.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 78, | for signal feedback to or from a common electrode
compensating for inter-electrode impedance. |
|
| | |
| 92 | Feedback to cathode impedance of a prior stage: |
| | This subclass is indented under subclass 91. Subject matter wherein the diverse signal feedback is derived
from an electrode other than the cathode and applied to the cathode
impedance of a prior stage whereby the diverse signal feedback path
includes or overlaps the cathode impedance feedback path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 100, | for amplifiers having multiple signal feedback paths
in general, including signal feedback to the input of a prior stage. |
|
| | |
| 93 | Including positive feedback: |
| | This subclass is indented under subclass 90. Subject matter including a signal feedback means whereby
the feedback has a component in phase with the signal applied at
the input electrode to which the signal feedback is applied.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 82, | for push-pull amplifiers having positive and negative
feedback. |
| 89, | for cathode-to-cathode feedback between adjacent
stages. |
| 101, | for positive and negative feedbacks in the same
path at different frequencies. |
| 104, | for positive and negative feedback, generally. |
| 112, | for positive feedback, generally. |
SEE OR SEARCH CLASS:
| 329, | Demodulators,
subclass 367 for an amplitude demodulator utilizing regenerative
feedback. |
| 331, | Oscillators, appropriate subclasses for oscillators operating
on the positive feedback principle. |
| 333, | Wave Transmission Lines and Networks,
subclasses 213+ for negative resistance and/or reactance
networks of the active element type which usually include positive
feedback. |
| 455, | Telecommunications,
subclass 336 for superregenerative receivers; and subclass 337
for regenerative receivers. |
|
| | |
| 94 | Frequency responsive means in cathode impedance feedback
path: |
| | This subclass is indented under subclass 87. Subject matter including in the "cathode impedance
to ground signal feedback path" or in shunt therewith circuit
means which acts on the signal feedback to affect some frequency component
of the signal feedback differently from the other frequency components
of the signal feedback, for example, a tuned circuit or filter circuit
which eliminates a frequency component, or an equalizer which emphasizes
or de-emphasizes the signal feedback amplitude of some frequency
or frequency range of the signal feedback with respect to others.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 107, | for amplifiers having phase shift means in the loop
path. |
| 109, | for amplifiers having frequency responsive signal
feedback means. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for passive coupling networks in general. |
|
| | |
| 95 | Nonlinear impedance means in cathode impedance feedback
path: |
| | This subclass is indented under subclass 87. Subject matter wherein the "cathode impedance signal
feedback path" has therein a nonlinear impedance circuit
element, which may be resistive, capacitive, or inductive, and whose
impedance is such, that the relationship for changes in voltage,
between the voltage across the nonlinear element to the current
flow therein is nonlinear.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 86, | for amplifiers having a variable impedance in the
feedback path varied by a separate control path. See the search
notes thereunder. |
| 110, | for amplifiers having a nonlinear impedance device
in the loop path. |
| 183, | for amplifiers having a D.C. interstage coupling
means including a nonlinear impedance element. See the search notes
thereunder. |
|
| | |
| 96 | Combined with control of bias voltage of signal amplifier: |
| | This subclass is indented under subclass 75. Subject matter combined with bias voltage control means
for a signal amplifying device.
| | (1)
Note. For the definition of an amplifier with bias voltage
control see subclass 129 below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 129+, | for amplifiers having bias voltage control means.
See the search notes thereunder. |
|
| | |
| 97 | Including D.C. path for signal feedback: |
| | This subclass is indented under subclass 75. Subject matter wherein the signal feedback path, from the
output electrode of the amplifying device from which the signal
feedback is derived to the input electrode of the amplifying device
to which the signal feedback is applied, is a D.C.. conductive path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching means for
input-output comparison including those with D.C. conductive feedback
paths. |
| 83, | for push-pull amplifiers having D.C. conductive
signal feedback paths. |
|
| | |
| 98 | In cascade amplifiers: |
| | This subclass is indented under subclass 75. Subject matter including at least two stages of amplification
(each as defined in the class definition) wherein the means for
coupling the input signal for each stage except the first is coupled
to the means for coupling the output signal of the preceding amplifier;
combined with signal feedback means above.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 88+, | for cathode-cathode signal feedback in cascaded
amplifiers. |
| 92, | for cascaded amplifiers with signal feedback to
the cathode impedance of a prior stage. |
|
| | |
| 99 | Multiple feedback: |
| | This subclass is indented under subclass 98. Subject matter including at least two signal feedback circuit
means as defined therein.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 88+, | for cascaded amplifiers having cathode-to-cathode
signal feedback. |
| 90+, | for amplifiers having cathode impedance signal feedback
combined with diverse type signal feedback coupling. |
|
| | |
| 100 | A feedback to input of a prior stage: |
| | This subclass is indented under subclass 99. Subject matter wherein at least one of the signal feedback
means has the signal feedback applied to the signal input of a prior
stage so that the path of such feedback means extends to include
all or a portion of at least one other signal feedback means (overlapping
feedbacks).
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 88+, | for cascaded amplifiers having cathode-to-cathode
signal feedback means. |
| 92, | for cascaded amplifiers including feedback to the
cathode impedance of a prior stage. |
|
| | |
| 101 | Positive and negative feedback in same path at different
frequencies: |
| | This subclass is indented under subclass 75. Subject matter wherein a single signal feedback circuit
means through an impedance shared by the same input and output circuits has
for currents flowing through the same shared feedback impedance
at one frequency a signal feedback in phase (positive feedback) with
the signal input where the signal feedback is applied and at least
at some other frequency a signal feedback component flowing through the
same feedback impedance, in opposite phase with the signal (negative
feedback).
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 82, | for amplifiers having at least one stage of push-pull
amplification including both positive and negative feedback. |
| 89, | for cascaded amplifiers having cathode-cathode signal
feedback between adjacent stages. |
| 93, | for amplifiers having cathode impedance feedback
and positive feedback. |
| 104, | for amplifiers having multiple signal feedbacks
including both positive and negative feedback. |
|
| | |
| 102 | Current and voltage feedback: |
| | This subclass is indented under subclass 75. Subject matter including signal feedback proportional to
the current flow through the output load which receives the amplified
signal, and signal feedback proportional to the voltage across the
output load.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 105, | for amplifiers with signal feedback from an impedance
in series with the output load (e.g., current feedback). |
|
| | |
| 103 | Multiple feedback paths: |
| | This subclass is indented under subclass 75. Subject matter including two or more signal feedback circuit
means as therein defined and not previously provided for in this
schedule.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 88+, | for cascaded amplifiers having cathode-cathode signal
feedback. |
| 90+, | for cathode impedance signal feedback combined with
diverse type signal feedback. |
| 99+, | for cascaded amplifiers having multiple feedbacks. |
| 102, | for amplifiers having current and voltage feedback. |
|
| | |
| 104 | Positive and negative feedback: |
| | This subclass is indented under subclass 103. Subject matter including at least one signal feedback means
having a component of the signal feedback in phase with the signal
at the point in the circuit where the signal is applied and at least
one signal feedback circuit means having a signal feedback component
which is in phase opposition with the signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 82, | for push-pull amplifiers having negative and positive
feedback means. |
| 89, | for cascaded amplifiers having cathode-cathode signal
feedback between adjacent stages. |
| 93, | for cathode impedance feedback combined with diverse
type feedback coupling including positive feedback. |
| 101, | for positive and negative feedback in the same path
at different frequencies. |
SEE OR SEARCH CLASS:
| 329, | Demodulators,
subclass 367 for an amplitude demodulator utilizing regenerative
feedback. |
| 331, | Oscillators, appropriate subclasses for oscillators operating
on the positive feedback principle. |
| 333, | Wave Transmission Lines and Networks,
subclasses 213+ for negative resistance and/or reactance
networks of the active element type which usually include positive
feedback. |
| 455, | Telecommunications,
subclass 336 for superregenerative receivers; and subclass 337
for regenerative receivers. |
|
| | |
| 105 | From impedance in series with output load (e.g., current
feedback): |
| | This subclass is indented under subclass 75. Subject matter wherein the signal feedback is from an impedance
in series with the output load which receives the amplified signal, whereby
the signal feedback voltage is proportional to the current flowing
in the output load.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 102, | for amplifiers having current and voltage feedback. |
|
| | |
| 106 | In series with input source: |
| | This subclass is indented under subclass 75. Subject matter wherein the "signal feedback circuit
means" is in series with the signal input source between
the point in the signal circuit from which the signal feedback is
derived to the point in the circuit at which the signal feedback
is applied. |
| | |
| 107 | Phase shift means in loop path: |
| | This subclass is indented under subclass 75. Subject matter wherein the "loop path" (see
(3) Note under subclass 75 for the definition of loop path) includes
voltage or current phase shift or delay means which may shift the
phase of the voltage or current of one signal frequency or signal
frequency feedback component with respect to another or shift the
phase of the voltage of the signal or signal feedback with respect
to the current.
| | (1)
Note. Transformer or amplifier means which inherently shift
the phase 1805 are not regarded as phase shift or voltage delay
means for this subclass. If such transformer or amplifier include
additional phase shift means classification is herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers having distributed parameter coupling
which may include electric wave delay means. |
| 101, | for amplifiers having positive and negative feedback
in the same path at different frequencies. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems,
subclasses 212 through 219for phase control systems in general. |
| 333, | Wave Transmission Lines and Networks,
subclasses 138+ for electric wave delay networks, of the passive type,
see the search notes thereunder. |
|
| | |
| 108 | Potentiometer common to signal and feedback path: |
| | This subclass is indented under subclass 75. Subject matter wherein the signal transmission path and
the "signal feedback circuit means" both include
a potentiometer or a part thereof in common.
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems, for voltage magnitude control systems in general,
including resistors. |
|
| | |
| 109 | Frequency responsive feedback means: |
| | This subclass is indented under subclass 75. Subject matter wherein the "signal feedback circuit
means" includes circuit means which acts on the signal
feedback to affect some frequency component of the signal feedback
differently from the other frequency components of the signal, as
for example, a tuned circuit which eliminates a frequency component
of the signal feedback or an equalizer which emphasizes or de-emphasizes
the amplitude of some frequency range of the signal feedback with respect
to others.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 94, | for frequency responsive cathode impedance feedback
means. |
| 107, | for signal feedback amplifiers including phase shift
means in the loop path including those involving frequency responsive
feedback means. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 28 and 167+ for frequency responsive passive
coupling networks in general. See the search notes thereunder. |
|
| | |
| 110 | Nonlinear impedance element in loop path: |
| | This subclass is indented under subclass 75. Subject matter wherein the "loop path" (see
(3) Note under subclass 75 for the definition of loop path) includes
a nonlinear impedance circuit element, which may be resistive, capacitive,
or inductive, and whose impedance is such for changes in voltage
applied thereto that the relationship between the voltage across such
element to the current flow through the element is nonlinear.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 86, | for amplifiers having a variable impedance in the
feedback path varied by a separate control path. See the search
notes thereunder. |
| 95, | for amplifiers having a nonlinear impedance element
in the cathode impedance feedback path. |
| 143, | for amplifiers having a thermally responsive impedance
in the signal path. |
| 183, | for amplifiers having a D.C. interstage coupling
means including a nonlinear impedance element. See the search notes
thereunder. |
|
| | |
| 111 | To or from an auxiliary grid or to the anode: |
| | This subclass is indented under subclass 75. Subject matter wherein the amplifying device or devices
involved are of the vacuum tube type and wherein the signal feedback
is derived from an electrode thereof other than the anode or cathode
and/or is applied to an electrode thereof other than the
cathode or control grid.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 160+, | for interstage signal coupling involving coupling
to the screen grid, plate, suppressor grid (and grid other than the
control grid or cathode). See search notes thereunder. |
| 162+, | for interstage signal coupling from a grid (from
an electrode other than anode or cathode). See search notes thereunder. |
|
| | |
| 112 | Positive feedback: |
| | This subclass is indented under subclass 75. Subject matter wherein the signal feedback has a component
in phase with the signal where the feedback is applied and which
is not provided for above.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 82, | for push-pull amplifiers including positive signal
feedback. |
| 89, | for cascaded amplifiers having cathode-cathode signal
feedback. |
| 93, | for cathode impedance signal feedback combined with
diverse type signal feedback including positive signal feedback. |
| 101, | for positive and negative feedback in the same path
at different frequencies. |
| 104, | for positive and negative feedbacks combined, generally. |
SEE OR SEARCH CLASS:
| 331, | Oscillators, appropriate subclasses for oscillators operating
on the positive feedback principle. |
| 333, | Wave Transmission Lines and Networks,
subclasses 213+ for negative resistance and/or reactance
networks of the active element type which usually include positive
feedback. |
| 455, | Telecommunications,
subclass 336 for superregenerative receivers; and subclass 337
for regenerative receivers. |
|
| | |
| 113 | POLYPHASE POWER SUPPLY (I.E., FOR AN ELECTRODE, CATHODE HEATER,
OR FILAMENT): |
| | This subclass is indented under the class definition. Subject matter including a polyphase power supply for the
energizing or bias voltage supply applied to any electrode or for
a filament or for any heater for a cathode electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 114+, | for amplifiers having unrectified power supply. |
| 199, | for amplifiers involving power or bias voltage supply.
See the search notes thereunder. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 13+ for plural load systems of the polyphase type. |
| 310, | Electrical Generator or Motor Structure, appropriate subclasses under
subclasses 10+ for dynamoelectric machine structure of the polyphase type. |
| 323, | Electricity: Power Supply or Regulation Systems, appropriate subclasses for systems in which a single
source of supply is connected to a single load and the system includes
means for controlling only the magnitude of the current, the voltage,
and/or the phase angle between the current and the voltage
in the system. The single source may be a polyphase source. |
| 336, | Inductor Devices,
subclasses 5+ for the structure of polyphase inductor devices. |
| 363, | Electric Power Conversion Systems, particularly
subclasses 148+ for phase conversion systems from one number of
phases to a different number of phases. |
|
| | |
| 114 | UNRECTIFIED A.C. POWER SUPPLY FOR AN ELECTRODE (I.E., NOT
THE HEATER): |
| | This subclass is indented under the class definition. Subject matter wherein the source of electrical energy which
is controlled by the electrical signal is an A.C. electrical source, which
is applied as an A.C. power supply directly to an electrode without
any intervening rectifiers to rectify the A.C. electrical supply.
| | (1)
Note. Special types of amplifiers are classified above and
subject matter involving unrectified A.C. as a power supply would
be classified with the special type of amplifier and not herein.
The amplifiers having general vacuum tube amplifying devices with
this feature are classified herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for vacuum tube amplifying devices series energized. |
| 113, | for amplifiers having a polyphase power supply. |
| 199, | for amplifiers involving power or bias voltage supply
means, generally. See also search notes thereunder. |
| 296, | and 297, for semiconductor amplifiers involving
bias or power supply circuits. |
SEE OR SEARCH CLASS:
| 363, | Electric Power Conversion Systems, appropriate subclasses thereunder, for power supply
means combined with means to convert A.C. to D.C. or vice versa. |
|
| | |
| 115 | Applied to filamentary cathode: |
| | This subclass is indented under subclass 114. Subject matter wherein the electrode, to which the A.C.
power supply voltage is applied, is a filamentary directly heated
cathode.
| | (1)
Note. A.C. power supply for heaters of indirectly heated
cathodes are not classified in this subclass but are classified
in subclass 113, above, in the special case where they involve a
polyphase power supply. Amplifiers with cathode filaments heated
by the anode current are classified in subclass 201 of this class.
Amplifiers with heater supply otherwise are classified in subclass
199. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems, appropriate subclasses indented under
subclass 94 , particularly subclasses 97 and 105+ for
subject matter involving A.C. power supply to cathodes or cathode heaters. |
|
| | |
| 116 | WITH BALANCED-TO-UNBALANCED COUPLING: |
| | This subclass is indented under the class definition. Subject matter including a circuit in the signal path in
the conductors of which electrical signal flows so that at any instant
the signal potential in the conductors is substantially equal and
opposite in sign with reference to ground or some other convenient
reference potential plane; and wherein further, in the signal path
there is included a circuit in the conductors of which signal flows
which is unbalanced to ground comprising a single-sided output load
usually of two conductors one of which is at ground or reference
potential.
| | (1)
Note. Subject matter as defined above including additional
unbalanced output or load circuits as set forth above is also classified
in this subclass. |
| | (2)
Note. Balanced circuits are considered as single sources
or single loads in this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 69, | for sum and difference amplifiers. |
| 117, | for amplifiers having unbalanced to balanced coupling. |
| 118, | for amplifiers including a push-pull stage. See
the search notes thereunder. |
| 301, | for semiconductor amplifiers having balanced to
unbalanced circuits. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 594 for miscellaneous circuits with particular coupling
or decoupling means. |
| 329, | Demodulators, appropriate subclasses for demodulators with balanced
to unbalanced coupling. |
| 333, | Wave Transmission Lines and Networks,
subclasses 4+ and 25+ for balanced to unbalanced passive
circuits. See the search notes under subclasses 4 and 25. |
|
| | |
| 117 | WITH UNBALANCED-TO-BALANCED COUPLING: |
| | This subclass is indented under the class definition. Subject matter including in the signal path a circuit electrically
unbalanced to ground, or a convenient electrical reference potential
plane, from a single source of electrical signal and having at some
subsequent location of the signal path, with or without one or more
intervening amplifying devices, a balanced circuit wherein at least
two of the conductors have at any instant electrical signal flowing
therethrough substantially equal and opposite in sign with reference
to ground or some other convenient reference plane.
| | (1)
Note. Balanced circuits are treated as single sources of
electrical signal or as single loads in this class. |
| | (2)
Note. Phase splitters are classified in this subclass. Phase
inverter amplifier circuits are classified in this subclass and subclass
116 above. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 116, | for amplifiers having balanced-to-unbalanced coupling. |
| 118, | for amplifiers having a push-pull stage. See the
notes and search notes thereunder. |
| 301, | for semiconductor amplifiers having unbalanced to
balanced circuits. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 594 for miscellaneous circuits with particular coupling
or decoupling means. |
| 329, | Demodulators, appropriate subclasses for demodulators with unbalanced
to balanced coupling. |
| 333, | Wave Transmission Lines and Networks,
subclasses 4+ and 25+ for unbalanced-to-balanced passive
circuits. See the search notes under the subclasses 4 and 25. |
|
| | |
| 118 | INCLUDING A PUSH-PULL STAGE: |
| | This subclass is indented under the class definition. Subject matter including two amplifiers as defined in the
class definition, the input electrodes of each of the amplifying
devices of the two amplifiers being balanced to ground or some other
convenient electrical reference plane, the source of electrical
signal being such, and so coupled to the input electrodes, that
at any instant the signal on each input electrode is substantially
equal and opposite in sign to the signal on the other input electrode;
and wherein the signal on the output electrodes of each of the amplifying
devices is similarly balanced to a convenient electrical reference plane.
| | (1)
Note. A balanced signal circuit is treated as a special case
of a single source or a single load, in this class. |
| | (2)
Note. A push-pull amplifier is treated as a single channel
with a single source and a single load in this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 55, | for push-pull amplifiers including a push-pull stage. |
| 69, | for sum and difference amplifiers similar in structure
to push-pull amplifiers. |
| 71+, | particularly subclass 72, for push-pull amplifiers
included in series energized vacuum tube arrangements. |
| 77, | for push-pull amplifiers having feedback compensation
to mitigate inter-electrode impedance effects. |
| 81+, | for amplifiers having at least one push-pull stage
having signal feedback. |
| 116, | for amplifiers with balanced-to-unbalanced coupling. |
| 117, | for amplifiers with unbalanced-to-balanced coupling
including phase splitters. |
| 262+, | for semiconductor amplifiers including a push-pull
stage. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 595 for miscellaneous circuits including push pull
circuits. |
| 333, | Wave Transmission Lines and Networks,
subclasses 4+ and 25+ for passive balanced networks.
See the search notes under subclasses 4 and 25. |
|
| | |
| 119 | Coupling to or from cathode in push-pull: |
| | This subclass is indented under subclass 118. Subject matter wherein the two amplifying devices in push-pull
are vacuum tube amplifying devices and wherein the input electrodes
or the output electrodes are the cathode electrodes of the vacuum
tube amplifying devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 158+, | for amplifiers with interstage coupling to the cathode
of an amplifying device. |
| 168, | and 172, for interstage coupling from the cathode. |
| 186+, | for input coupling to the cathode. See the search
notes thereunder. |
| 193+, | for output coupling from the cathode. See search
notes thereunder. |
|
| | |
| 120 | Interstage coupling between push-pull: |
| | This subclass is indented under subclass 118. Subject matter including at least two cascaded stages of
amplification, each stages as defined in subclass 118 above and
each stage excepting the first having its signal input coupled to
the signal output of the preceding stage involving specific details
or distinctive characteristics of the coupling between the stages.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 157+, | for interstage coupling. See the search notes thereunder. |
|
| | |
| 121 | D.C. coupling: |
| | This subclass is indented under subclass 120. Subject matter wherein the signal coupling path from the
output electrode of each amplifying device of the preceding stage
to the input electrode of the corresponding device of the following
stage is a D.C.. conductive path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 159, | 161, 163, 172, and 181+, for various types
of interstage D.C. coupling. See also the search notes thereunder. |
|
| | |
| 122 | Input and/or output coupling for push-pull: |
| | This subclass is indented under subclass 118. Subject matter involving specific details or distinctive
characteristics of the input and/or output circuits coupling
the source to the amplifying devices and the amplifying devices to
a load, respectively.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 185, | for amplifier input networks. See the notes and
search notes thereunder. |
| 192, | for amplifier output networks. See the notes and
search notes thereunder. |
|
| | |
| 123 | Power or bias supply circuits and control thereof: |
| | This subclass is indented under subclass 118. Subject matter including means to control the power supply
and/or bias voltage supply applied to the electrodes of
the amplifying devices; and/or subject matter under subclass 118
involving specific details or distinctive characteristics of the
power or bias voltage supply of the amplifying devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 127+, | for amplifiers with control of power supply or bias
voltage. See the notes and search notes thereunder. |
| 129+, | for amplifiers with control of input electrode or
gain control electrode bias. See the notes and search notes thereunder. |
| 199+, | for amplifier power or bias supply voltages. See
the notes and search notes thereunder. |
|
| | |
| 124 | WITH PLURAL AMPLIFIER CHANNELS (E.G., PARALLEL AMPLIFIER
CHANNELS): |
| | This subclass is indented under the class definition. Amplifier systems wherein there are at least two signal
channels each containing an amplifier as defined in the class definition, (Section
I).
| | (1)
Note. For this and indented subclasses such amplifier channels
may be separate; in parallel with a common source and a common load;
or in branched circuit channels from separate sources or to separate
loads. |
| | (2)
Note. Sum and difference amplifiers involving two or more
signal inputs to the same channel or a different channel where the
output is proportionally the sum or difference of the plural inputs
are not classified herein. See the search notes below. |
| | (3)
Note. A balanced circuit is regarded as a single source or
load for the purposes of classification in these subclasses. A push-pull
amplifier is regarded as a single amplifier channel for purposes
of classification in this class. Balanced circuits and push-pull
amplifiers are to be found in this class. |
| | (4)
Note. The plural channels need not amplify or operate simultaneously
to be classified herein. Subject matter involving plural channels
with switching means to select with alternatively one or more channels
to amplify a signal a classified in this or indented subclasses. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for amplifiers having diverse type amplifying devices. |
| 53, | for amplifiers having distributed parameter coupling. |
| 55, | for amplifiers having distributed parameter coupling; |
| 69, | for sum and difference amplifiers. See (2) Note
above. |
| 70+, | for amplifiers with series arranged amplifier devices. |
| 71+, | for series energized amplifier devices; |
| 73, | for plural outputs. |
| 74, | for plural separate signal inputs. |
| 77, | for push-pull amplifiers with feedback compensation
for the effects of inter-electrode capacitance (e.g., neutralization). |
| 81+, | for signal feedback amplifiers having at least one
push-pull stage. |
| 84, | for signal feedback amplifiers with plural amplifier
channels. |
| 116, | for amplifiers with balanced-to-unbalanced coupling. |
| 117+, | for amplifiers having unbalanced-to-balanced coupling;
and subclasses |
| 118+, | for amplifiers including a push-pull stage. |
| 147, | for amplifiers having plural input sources. |
| 148, | for amplifiers having plural loads. |
| 151, | for cascaded amplifiers with means to by-pass a
stage. |
| 252+, | and 295, for plural semiconductor amplifier channels. |
| 262+, | 301 for semiconductor amplifiers; |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 11+ and 43+ for plural load circuit and supply circuit
systems respectively. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous nonlinear
circuits utilizing electron tube or semiconductor devices. |
| 333, | Wave Transmission Lines and Networks,
subclasses 1+ for plural channel passive network systems. |
| 381, | Electrical Audio Signal Processing and Systems,
subclass 77 for program distribution systems involving distribution
of a program to a plurality of local stations where the program
is amplified and reproduced. |
|
| | |
| 125 | D.C. and A.C. amplifier channels: |
| | This subclass is indented under subclass 124. Subject matter wherein at least one of the signal channels
has a D.C. conductive path from source to load, or where branched
channels are involved, from or to the common junction point of the
channels to the separate loads or from the separate sources or between
common junction points in parallel channels; and at least one other
channel has its signal transmission path, as set forth above, involves
coupling circuits which will conduct only A.C. signals, because
of signal coupling by a series condenser or transformer, and which
will not conduct D.C. in that signal channel circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching input-output
comparison. |
| 10, | for modulator-demodulator type amplifiers. |
|
| | |
| 126 | Amplifying different frequencies in different channels: |
| | This subclass is indented under subclass 124. Subject matter wherein at least one of the channels amplifies
a signal of a different frequency from at least one other channel.
SEE OR SEARCH CLASS:
| 381, | Electrical Audio Signal Processing Systems and
Devices,
subclasses 111+ , for amplifier systems including microphones and/or
loud speakers having plural amplifier channels which pass different
frequency bands. |
|
| | |
| 127 | WITH CONTROL OF POWER SUPPLY OR BIAS VOLTAGE: |
| | This subclass is indented under the class definition. Subject matter combined with means to control the voltage
of the source of electrical energy which is supplied to the amplifying device,
or combined with means to control a bias voltage applied to an electrode,
such control means, generally, being applied to stabilize the power
supply or bias voltage or to alter the operation of the amplifying
device in a predetermined manner as, for example, to control the signal
amplitude, or means to regulate the power, heater, or filament supply
of the amplifying device.
| | (1)
Note. Limiters of the active element type which "clip" the
signal are not classified herein. Limiters combined with amplifiers
where the bias of an electrode of the amplifier is controlled to "accommodate" a
given maximum signal (where there is no clipping of the signal) are
classified herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching input-output
comparison. |
| 11, | for amplifiers having D.C. reinsertion circuits. |
| 51, | for amplifiers combined with automatic disabling
switch means. |
| 52, | for amplifiers having pilot frequency control means. |
| 59, | for amplifiers having light control or activated
means. |
| 70+, | for series energized vacuum tube amplifiers. |
| 85, | for signal feedback amplifiers having an amplifier
in the feedback path including the control of bias of such feedback
amplifiers. |
| 86, | for signal feedback amplifiers having a separately
controlled variable impedance in the feedback path. |
| 96, | for signal feedback amplifiers having bias voltage
control of the signal amplifier. |
| 113, | for polyphase power supply. |
| 114+, | for unrectified A.C. power supply for an electrode. |
| 123, | for control of bias voltage or power supply voltage
in push-pull amplifiers. |
| 143, | for amplifiers having a thermally responsive impedance. |
| 144+, | for amplifiers having a variable impedance for the
signal path varied by a separate control path. |
| 164, | for cascaded amplifiers having an electronic tube
or diode in the interstage coupling. |
| 174, | for cascaded amplifiers having an electro-mechanical
transducer (e.g., piezoelectric crystal in the interstage coupling
path. |
| 179, | and 180, for cascaded amplifiers having an inductance
in the anode or grid circuit, or a resistance in the anode and grid
circuit in the capacitance-coupled interstage coupling, respectively. |
| 183, | for cascaded amplifiers having a nonlinear device
in the D.C. interstage coupling path. |
| 199+, | for amplifiers with significant power or bias voltage
supply. |
| 254, | and 278+, for semiconductor amplifiers
having signal amplitude (volume level) control including such means where
the bias is controlled. |
| 290, | for semiconductor amplifiers having D.C. feedback
bias control for stabilization. |
| 297, | for series energized cascaded semiconductor amplifiers. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 31+ and 52+ for current or voltage control
of electrical transmission or interconnection systems. |
| 323, | Electricity: Power Supply or Regulation Systems, for limiters of the active element type which "clip" the
signal; see appropriate subclasses for voltage magnitude control
systems generally. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 309+ for amplitude limiting means. |
| 329, | Demodulators, appropriate subclasses for automatic control of
the bias of a demodulating element. |
| 333, | Wave Transmission Lines and Networks, particularly
subclasses 2+ for automatic control of plural channel passive
networks, subclass 14 for compressors and expanders, subclasses
15 and 16 for pilot signal controlled systems, subclasses 17.1+ for automatically
controlled lines or networks, and subclass 81 for attenuators.
See also the search Notes under these subclasses. |
| 338, | Electrical Resistors, for the structure of resistors, rheostats, and potentiometers,
per se. |
| 455, | Telecommunications,
subclasses 234.1 through 253.2for automatic volume control in radio receivers;
and subclasses 343.1-343.6 for particular power or bias supply
for radio receivers. |
|
| | |
| 128 | Control means for anode of screen grid circuit: |
| | This subclass is indented under subclass 127. Subject matter wherein the "combined control means" is
in the circuit from the power supply or bias voltage source means
to the anode or screen grid electrode of a vacuum tube amplifying
device or in shunt therewith, in such manner, as to control the
power supply or bias voltage applied to the anode or screen grid electrode.
| | (1)
Note. Ordinary anode or screen grid resistors as such are
not control means such as is classified in this subclass. However
glow tubes, nonlinear resistors, diodes, vacuum tubes, etc., in
the anode or screen grid supply circuit for voltage regulation and
related subject matter are classified herein. Such matter involving ordinary
resistors or other nonlinear impedances in the power or bias supply circuits
are classified in the appropriate coupling subclass, when the particular nonlinear
element affects the signal coupling, and not the power supply.
Subject matter wherein such impedance is isolated from the signal
path or is involved only in the power supply circuit or forms the
means for isolating the power supply circuit and is not involved
in signal coupling as, for example, signal by-pass means for the
power supply, classification is in the appropriate subclass indented
under subclass 199 below. |
| | (2)
Note. Nonlinear impedances, vacuum tube impedances, thermal
impedances, etc., in amplifier circuits as indicated are classified
in this class. See the search notes below. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 52, | for pilot frequency control means which may utilize
thermal or other nonlinear control means. |
| 70+, | for series energized vacuum tube amplifier devices
having the anode energized through the discharge path of a controlled
vacuum tube. |
| 86, | for signal feedback amplifiers having a variable
impedance in the feedback path. |
| 95, | and 110, for nonlinear impedance in the cathode
impedance feedback path and for a nonlinear impedance element in
the loop path of feedback amplifiers respectively. |
| 96, | for feedback amplifiers combined with control of
bias voltage of the signal amplifier. |
| 123, | for control of anode or screen grid voltage in push-pull
amplifiers. |
| 131, | for amplifiers having a bias control voltage applied
to an electrode separate and distinct from the signal input electrode. |
| 143, | for a thermally responsive impedance in the amplifier
circuit (when not specifically involved in power or bias supply
circuit as in subclass 128). |
| 144+, | for variable impedance for the signal channel, controlled
by a separate control path, particularly subclass 145 where the
variable impedance is an electron tube or a diode. |
| 164, | for amplifier interstage coupling including an electronic
tube or diode. |
| 174, | for amplifiers having an electromechanical transducer
(e.g., piezoelectric crystal) in an interstage coupling circuit. |
| 183, | for amplifiers having a nonlinear device in a D.C.
interstage coupling. |
| 254, | and 278+, for semiconductor amplifiers
including nonlinear impedance elements used for signal volume level control. |
| 256, | 272 and 289, for semiconductor amplifiers including
transistor temperature control. |
| 290, | for semiconductor amplifiers having bias control
D.C. feedback stabilization which may involve nonlinear impedance
elements. |
| 291, | for semiconductor signal feedback amplifiers which
may involve nonlinear impedance elements. |
| 296, | 297, for semiconductor cascaded amplifiers series
energized for power involving bias or power supply circuitry. |
| 299+, | for semiconductor amplifiers combined with a semiconductor
impedance device. |
|
| | |
| 129 | With control of input electrode or gain control electrode
bias: |
| | This subclass is indented under subclass 127. Subject matter wherein the "means to control the
bias voltage" is applied to an input electrode of the amplifying
device, or to an electrode separate and distinct from the signal
input electrodes and in vacuum tube amplifiers also separate and
distinct from the anode or screen grid electrodes in order to control
the bias of such electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching input-output
comparison. |
| 11, | for amplifiers with D.C. reinsertion circuits. |
| 52, | for amplifiers have pilot frequency control means. |
| 85, | for signal feedback amplifiers having an amplifier
in the feedback path including such feedback amplifiers having means
to control the bias of an input or gain control electrode, thereof. |
| 96, | for amplifiers having signal feedback with means
to control the bias voltage on an electrode of the signal amplifier. |
| 123, | for bias voltage control of input or gain control
electrode in push-pull amplifiers. |
| 254, | and 278+, for semiconductor amplifiers
having signal volume level control. |
| 290, | for semiconductor amplifiers having D.C. feedback
bias control for stabilization. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems,
subclasses 227 and 291 for discharge control devices for voltage
magnitude control including bias control means. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 309+ for miscellaneous circuits including bias voltage
control means for amplitude limiting. |
| 333, | Wave Transmission Lines and Networks,
subclasses 14 , 15 and 213+ for companders, pilot line
controlled systems, and active element negative resistors or reactors,
respectively including such subject matter with bias control means. |
| 363, | Electric Power Conversion Systems, appropriate subclasses for electrical conversion,
including control of the line voltage. |
| 455, | Telecommunications,
subclasses 234.1 through 253.2for automatic volume control in radio receivers;
and subclasses 343.1-343.6 for particular power or bias supply
for radio receivers. |
|
| | |
| 130 | Bias controlled by separate external control source: |
| | This subclass is indented under subclass 129. Subject matter wherein the "means to control the
bias voltage" includes a source of control voltage from
a system outside the amplifier system itself.
| | (1)
Note. An example is a seismic amplifier wherein a battery
not involved in supplying amplifier power or bias voltage charges
an RC circuit which is applied to the control grid or an input grid
of the amplifier when the shot blast is fired. Such additional
means where it includes the detector or other related means of the seismic
system, per se, is not classified herein. See the Search Class notes below. |
| | (2)
Note. Subject matter, wherein the control voltage is derived
from a special pilot frequency voltage transmitted to the amplifier
with the signal to be amplified, is not classified herein. |
| | (3)
Note. Subject matter wherein an oscillator (exclusive of
any other source external to the amplifier) supplies the control bias
is not classified herein. Also sources of bias voltage as such,
where no cooperation from a system outside the amplifier is involved
are classified with amplifiers. Where specific details of the external
system are claimed as in the example under (1) Note above, as qualified
in the last three lines, classification is not with amplifiers but
with the external system. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 51, | for amplifiers combined with automatic disabling
switch means. |
| 52, | for subject matter, wherein the control voltage
is derived from a special pilot frequency voltage transmitted to
the amplifier with the signal to be amplified. See (2) Note above. |
| 85, | for amplifiers having an amplifier in the feedback
path including bias control means for an electrode of such amplifier. |
| 86, | for amplifiers having a variable impedance in a
feedback control path varied by a separate control path. |
| 137, | for amplifiers having bias control means including
an oscillator in the control means. See (3) Note above. |
| 143, | for amplifiers having a thermally responsive impedance
which may be controlled from an external control source. |
| 144+, | for amplifiers having a variable impedance for the
signal channel controlled by a separate control path which may be
from an external source. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 309+ for miscellaneous circuits including bias voltage
control means for amplitude limiting. |
| 333, | Wave Transmission Lines and Networks,
subclasses 15 , 16 and 17.1+ for pilot line, pilot current
and automatically controlled passive wave transmission systems. |
| 367, | Communications, Electrical: Acoustic Wave Systems
and Devices,
subclasses 14+ , for means means where including the detector or
other related means of the seismic system, per se. See (1) Note
above. |
| 455, | Telecommunications, particularly
subclasses 232.1+ and 341+, for similar subject matter in
radio receivers. |
|
| | |
| 131 | Control of bias on separate gain control electrode: |
| | This subclass is indented under subclass 129. Subject matter wherein the bias control voltage is applied
to an electrode of the amplifying device separate and distinct from
the electrodes to which the signal input is applied.
| | (1)
Note. Subject matter as above in which the separate and distinct
electrode to which the bias voltage is applied is the screen grid
or anode of a vacuum tube amplifying device is not classified herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 128, | for subject matter as above in which the separate
and distinct electrode to which the bias voltage is applied is the screen
grid or anode of a vacuum tube amplifying device. |
|
| | |
| 132 | Frequency selective means to select control signal from
amplifier channel: |
| | This subclass is indented under subclass 129. Subject matter wherein the "means to control the
bias voltage" is derived from the electrical signal channel
through a frequency selective means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 52, | for pilot frequency control amplifiers including
subject matter wherein the pilot control is derived from the signal channel
by frequency selective means. |
| 85, | for amplifiers having an amplifier in the feedback
path including those having bias voltage control which may be derived
by frequency selective means. |
| 86, | for amplifiers having a variable impedance means
in the signal feedback path controlled by a separate control which
may be derived by a frequency selective means from the signal channel. |
| 109, | for signal feedback amplifiers having frequency
responsive means in the feedback path. |
| 143, | for amplifiers having thermally responsive impedance
which may be controlled by a voltage derived through a frequency
selective means from the signal channel. |
| 144+, | for amplifiers having a variable impedance for the
signal channel controlled by a separate control path, wherein the
control voltage may be derived from the signal channel by a frequency
responsive means. |
|
| | |
| 133 | Different bias control means for different stages of cascade
amplifier: |
| | This subclass is indented under subclass 129. Subject matter including at least two stages of amplification
(each stage as defined in the class definition with at least two
such stages as defined in subclass 129) such that the input signal
of each stage except the first is the output signal of the preceding
stage and wherein the bias control for each of at least two of the stages
as defined in subclass 129 has some characteristic or characteristics
distinctive from the other. |
| | |
| 134 | Plural different bias control voltages provided by separate
means: |
| | This subclass is indented under subclass 129. Subject matter including at least two separate and distinct
bias voltage control means as therein defined, wherein the control
voltages are applied to input or gain control electrodes, and which
may be applied to a single amplifying device or to more than one
amplifying device.
| | (1)
Note. The two separately developed bias control means may
be combined or compared or separately applied in some manner as
a single bias control means to a single electrode. | |
| | |
| 135 | Amplitude limiting or bias voltage: |
| | This subclass is indented under subclass 129. Subject matter including means to limit the maximum amplitude
of the bias control voltage.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 11, | for amplifiers having D.C. reinsertion circuits. |
| 138, | for amplifiers with voltage delay for bias control
where the bias control is not effective until a predetermined minimum
voltage is reached where such minimum voltage is fixed by biasing
a rectifier or control discharge device so that it will not conduct
until such voltage is reached. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 309+ for miscellaneous circuits with amplitude limiting means. |
| 329, | Demodulators, appropriate subclasses for automatic control of
the bias of a demodulating element. |
|
| | |
| 136 | Bias control signal from input of amplifier: |
| | This subclass is indented under subclass 129. Subject matter wherein "the bias control voltage" is
derived from the input circuit of the amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching for input-output
comparison including those amplifiers wherein a bias control voltage
for drift correction is developed from such comparison means. |
| 11, | for amplifiers having D.C. reinsertion circuits. |
|
| | |
| 137 | Oscillator supplies or controls bias: |
| | This subclass is indented under subclass 129. Subject matter wherein the bias voltage control means includes
an oscillator which may be itself controlled by a bias voltage means
and from which a signal amplifier bias voltage is derived, or from
which a control voltage, usually constant, is derived.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 52, | for amplifiers having pilot frequency control means. |
| 130, | for amplifiers including bias voltage control from
a source in a system external to and independent from the amplifier.
See (3) Note under subclass 130 above. |
|
| | |
| 138 | Bias controlled by biased rectifier or discharge device: |
| | This subclass is indented under subclass 129. Subject matter wherein the "bias voltage control
means" includes a rectifier or discharge device which is
biased in such a manner that the rectifier or discharge device will
not conduct until a predetermined voltage is reached, which imparts
to the control means a "voltage delay" action
and wherein the minimum voltage at which bias control begins may
be predetermined.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 134, | for amplifiers having plural different bias voltages
provided by separate means including those with biased rectifiers
or discharge devices. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 309+ for miscellaneous threshold limiters of the active
element type. |
|
| | |
| 139 | Electronic tube controls bias: |
| | This subclass is indented under subclass 129. Subject matter wherein "the bias voltage control
means" includes an electronic tube to control the bias
voltage which tube may be a gas tube or vacuum tube having a means
for control thereof while the tube is in operation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching input-output
comparison including those with electronic tubes for control. |
| 11, | for amplifiers having D.C. reinsertion circuits. |
| 85, | for amplifiers having amplifiers in the feedback
path including bias control for the feedback amplifier. |
| 86, | for feedback amplifiers having a variable impedance
in the feedback path varied by a separate control means, including
those wherein the variable impedance is an electronic tube. |
| 95, | and 110, for signal feedback amplifiers with nonlinear
impedance which may be an electronic tube. |
| 96, | for signal feedback amplifiers wherein the signal
amplifier has bias voltage control means, including amplifiers with
an electron tube in such bias control means. |
| 114, | for amplifiers with oscillators supplying or controlling
the bias. |
| 123, | for push-pull amplifiers having bias voltage control
means including those with electronic tubes, in the bias control
means. |
| 134, | for amplifiers with plural different bias voltages
including electronic tube. |
| 138, | for amplifiers controlled by biased rectifiers or
discharge devices. |
| 145, | for amplifiers having an electronic tube or diode
as a variable impedance for the signal channel, controlled by a separate
control path. |
| 164, | for amplifiers with an electronic tube or diode
in the interstage coupling. See the search notes thereunder. |
| 296, | for semiconductors amplifiers including those with
other transistors for bias control. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems, appropriate subclasses, for electronic tubes in
voltage magnitude control circuits generally. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 530+ for miscellaneous electron tube circuits with bias
control means. |
| 333, | Wave Transmission Lines and Networks,
subclass 14 for amplitude compression and expansion systems, subclasses
15 and 16 for pilot signal controlled systems, 17.1+ for
automatically controlled systems and 213+ for negative
resistance or reactance active element networks. |
|
| | |
| 140 | Rectifier in bias control circuit: |
| | This subclass is indented under subclass 129. Subject matter combined with a rectifier in "the bias
voltage control means".
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers having periodic switching input-output
comparison. |
| 11, | for amplifiers having D.C. reinsertion circuits. |
| 52, | for pilot frequency controlled amplifiers. |
| 85, | for amplifiers having amplifiers in the feedback
path including those with bias voltage control having rectifiers in
the control means. |
| 86, | for amplifiers having variable impedance in the
feedback path controlled by a separate control path. |
| 95, | and 110, for signal feedback amplifiers having nonlinear
means which may be a diode. |
| 96, | for signal feedback amplifiers wherein the signal
amplifier is provided with bias control including such bias control
containing a rectifier. |
| 123, | for push-pull amplifiers including those having
bias control means with rectifiers therein. |
| 134, | for amplifiers having plural different bias voltages
provided by separate means including those having biased rectifiers
in the control circuit. |
| 138, | for amplifiers having bias voltage control means
including a biased rectifier or discharge device. |
| 145, | for amplifiers having an electronic tube or diode
as a variable impedance for the signal channel controlled by a separate
control path. |
| 164, | for amplifiers having a diode in the interstage
coupling (see search notes under subclass 164). |
| 254, | and 278+, for semiconductor amplifiers
having signal volume level control. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 330 for miscellaneous electron tube circuits with amplitude
limiting and including a rectifier. |
| 363, | Electric Power Conversion Systems, appropriate subclasses for rectifier circuits. |
|
| | |
| 141 | Time constant circuit in bias control circuit: |
| | This subclass is indented under subclass 129. Subject matter wherein "the bias voltage control
means" includes a circuit of resistive and reactive elements,
usually of resistive and capacitive elements, which serves to filter
or "smooth out" the D.C. bias voltage applied
for control purposes to the amplifier device and wherein specific
details or distinctive characteristics of such circuit are claimed.
| | (1)
Note. Excluded from this subclass are the resistive capacitive
networks for self-biasing a vacuum tube amplifying device. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 142, | for resistive capacitive networks for self-biasing
a vacuum tube amplifying device |
| 143, | for amplifiers having a thermally responsive impedance
element including those with separate control thereof. |
| 144+, | for variable impedance for signal channel controlled
by separate control path. |
| 199+, | for amplifiers and their power or bias voltage supply. |
| 254, | and 278+, for semiconductor amplifiers
having signal amplitude (volume level) control. |
| 290, | for semiconductor amplifiers having D.C. feedback
for bias control. |
| 296, | and 297, for semiconductor device bias or power
supply circuitry. |
SEE OR SEARCH CLASS:
| 320, | Electricity: Battery or Capacitor Charging or
Discharging,
subclasses 166+ for charging or discharging a capacitor, per se. |
| 333, | Wave Transmission Lines and Networks,
subclasses 138+ , for passive time delay networks, subclasses 181+, for
smoothing type passive filter networks. |
| 363, | Electric Power Conversion Systems,
subclasses 44+ for conversion systems including D.C. smoothing
filter networks. |
| 455, | Telecommunications,
subclasses 234.1 through 253.2for automatic volume control in radio receivers;
and subclasses 343.1-343.6 for particular power or bias supply
for radio receivers. |
|
| | |
| 142 | Cathode resistor supplies bias (e.g., self-biasing circuits): |
| | This subclass is indented under subclass 129. Subject matter involving a vacuum tube amplifying device
whose input electrode bias voltage and/or bias control
voltage for the same amplifying device is supplied from a resistive
circuit network in the cathode to ground path of the vacuum tube
amplifying device whereby the plate current flowing through such
resistor, which is usually by-passed for signal current frequencies,
develops a D.C. bias voltage at the cathode.
| | (1)
Note. The subject matter in this subclass includes both adjustable
self-biasing means cathode circuit self-biasing means, per se, without
an adjustable feature, for vacuum tube amplifying device input electrodes.
Input electrode bias means without a control feature is classified
elsewhere. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for amplifiers having series energized amplifiers
devices. |
| 87+, | for cathode impedance feedback. |
| 203, | and 204, for input electrode biasing. See (1) Note
above. |
| 254, | and 278+, for semiconductor transistor
amplifiers having signal amplitude (volume level) control. |
| 290, | for semiconductor amplifiers having D.C. bias control
feedback for stabilization. |
| 296, | and 297, for semiconductor amplifiers involving
bias or power supply circuitry. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 530+ for miscellaneous electron tube circuits with particular bias
means. |
|
| | |
| 143 | THERMALLY RESPONSIVE IMPEDANCE: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifier contains in its circuit
an impedance element whose impedance value is responsive to the
temperature changes therein by reason of the heat generated by the
current flow therethrough, or the ambient temperature of the impedance
element, or whose impedance value may be changed by separate electrical
control means or other heat control means.
| | (1)
Note. Heat responsive impedance elements are species of nonlinear
impedance elements and, as such, when appearing in a cathode impedance
feedback circuit or generally in the loop path of a feedback amplifier
are not in this subclass. Nonlinear impedances, including thermal
impedances, in a feedback path which are varied by separate control means
are classified elsewhere. Thermally responsive impedance means form a
control means and when appearing in the voltage or power supply
circuits of a push-pull amplifier are classified elsewhere in this
class; and when appearing in the power supply or bias supply circuits,
as for example, in the circuit from the voltage power supply to
the anode or screen grid or in the bias supply circuit so as to
control the bias of a vacuum tube amplifier device, classification
is not herein but in the appropriate subclass of this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 86, | for nonlinear impedances, including thermal impedances,
in a feedback path which are varied by separate control means.
See (1) Note above. |
| 95, | and 110, for heat responsive impedance elements
when appearing in a cathode impedance feedback circuit or generally
in the loop path of a feedback amplifier . See (1) Note above. |
| 123, | for thermally responsive impedance means forming
a control means and appearing in the voltage or power supply circuits
of a push-pull amplifier. |
| 127+, | when appearing in the power supply or bias supply
circuits, as for example, in the circuit from the voltage power supply
to the anode or screen grid or in the bias supply circuit so as
to control the bias of a vacuum tube amplifier device. See (1) Note
above. |
| 144+, | for variable impedance for the signal channel controlled
by separate control path. |
| 157+, | appropriate subclasses thereunder for amplifier
interstage coupling which may include a nonlinear device other than
one thermally responsive, particularly subclass 164, for electronic tube
or diode, and subclass 174, for electromechanical transducer (e.g., piezo-electric
crystal) in the interstage coupling, and subclass 183, for a nonlinear
device generally (other than thermally responsive) in a D.C. interstage
coupling circuit. |
| 185+, | for nonlinear impedance elements, other than thermally
responsive,in amplifier input circuits. |
| 192+, | for nonlinear impedance elements, other than thermally
responsive, in amplifier output circuits. |
| 256, | 272 and 289+, for semiconductor amplifiers
with transistor temperature control. |
| 296, | and 297, for semiconductor amplifiers involving
bias or power supply circuitry. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems,
subclass 294 for thermally responsive impedance means for voltage
magnitude control, generally. |
| 336, | Inductor Devices, appropriate subclasses for inductor structure particularly
subclass 30 , for condition responsive inductor adjusting means, including
those responsive to thermal conditions. |
| 338, | Electrical Resistors,
subclasses 20+ for resistors whose value is responsive to the
current therethrough or the voltage thereacross and subclasses 25+ for
resistors whose value varies in response to ambient temperature
conditions. |
| 361, | Electricity: Electrical Systems and Devices,
subclass 282 for thermally responsive condensers, per se. |
|
| | |
| 144 | VARIABLE IMPEDANCE FOR SIGNAL CHANNEL CONTROLLED BY SEPARATE
CONTROL PATH: |
| | This subclass is indented under the class definition. Subject matter wherein there is provided for the signal
transmission path a variable impedance element or circuit which
may be a variable resistance, or reactance, whose impedance is controlled
by a separate control means.
| | (1)
Note. Examples of control of variable impedances classified
in this and indented subclasses are; a control voltage secured from
the signal output which may be rectified, filtered and applied to
a biased diode or to the control electrode of an electronic tube
to vary its impedance, or to control an electric motor which may
vary a potentiometer or adjustable reactance in the signal path. |
| | (2)
Note. Considering the signal coupling means as a four terminal
network the "variable impedance" of the subclass may
be in series between corresponding terminals or in shunt across
the signal transmission path. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 52, | for amplifiers having pilot frequency control means. |
| 70+, | for series energized vacuum tube amplifiers. |
| 85, | for signal feedback amplifiers having an amplifier
in the feedback path. |
| 86, | for signal feedback amplifiers having a variable
impedance in the feedback path varied by a separate control path. |
| 95, | and 110, for signal feedback amplifiers having a
nonlinear impedance in the feedback path. |
| 96, | for signal feedback amplifiers having means to control
the amplifier bias voltage. |
| 108, | for potentiometer common to signal and feedback
paths. |
| 127+, | for amplifiers having control of power supply or
bias voltage, particularly subclasses 138, 139, and 140. |
| 143, | for thermally responsive impedance in the signal
path including those varied by a voltage or other means from a separate
control path. |
| 155, | for amplifiers having unicontrol coupling. |
| 164, | for cascaded amplifiers having an electronic tube
or diode in an interstage coupling circuit. |
| 174, | for cascaded amplifiers having an electromechanical
transducer (e.g., piezo-electric crystal) in an interstage coupling
path. |
| 183, | for cascaded amplifiers having a nonlinear device
in a D.C. interstage coupling. |
| 185+, | for variable impedance in amplifier input networks. |
| 192+, | for variable impedance in amplifier output networks. |
| 293, | and 296, for series energized semiconductor amplifiers. |
| 299+, | for combined diverse type semiconductors where one
may be a variable impedance for the signal transmission path. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems,
subclasses 234 through 289for transformer and impedance systems for voltage
magnitude control. |
| 324, | Electricity: Measuring and Testing,
subclasses 98 , 99+, and 101 for electrical measuring
and testing circuits having bridges with variable impedances thereon,
which are varied by a separate control means. |
| 333, | Wave Transmission Lines and Networks, appropriate subclasses particularly
subclasses 14 , 15, 16, 17.1+, 81, and 213+ for
wave transmission systems with variable impedance in the wave transmission
path. |
| 334, | Tuners, appropriate subclasses for tuners, per se. |
| 336, | Inductor Devices, appropriate subclasses for the structure of variable inductors. |
| 338, | Electrical Resistors, appropriate subclasses for the structure of variable resistance
devices. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 277+ for variable condenser structure. |
|
| | |
| 145 | Electron tube or diode as impedance: |
| | This subclass is indented under subclass 144. Subject matter wherein the variable impedance means is an
electron tube, either vacuum tube or gaseous which has a control
means effective during operation of the tube, or a diode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for series energized vacuum tube amplifying devices. |
| 85, | for signal feedback amplifiers having an amplifier
in the feedback path. |
| 138, | 139 and 140, for amplifiers having means to control
the input electrode bias voltage including respectively, biased
rectifiers or discharge devices, electronic tube, or rectifier in
the bias control circuit. |
| 164, | for cascaded amplifiers having an electronic tube
or diode in the interstage coupling circuit. |
| 185+, | for amplifier input coupling networks which may
have an electronic tube or diode as an impedance therein. |
| 192+, | for amplifier output coupling networks which may
have an electronic tube or diode impedance therein. |
| 299+, | for combined diverse type semiconductors where one
of the semiconductors may be a diode or transistor impedance for
the signal transmission path. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems,
subclasses 227 and 291 for discharge devices on voltage magnitude
control systems generally. |
| 333, | Wave Transmission Lines and Networks,
subclasses 213+ for negative resistance and/or reactance
networks of the active element type. |
| 334, | Tuners,
subclasses 14+ for a tuner unit in which a reactance tube is used. |
|
| | |
| 146 | WHEATSTONE BRIDGE WITH AMPLIFIER IN AT LEAST ONE ARM: |
| | This subclass is indented under the class definition. Subject matter wherein the four arms of a Wheatstone bridge
comprise four impedances of the amplifier circuit in such manner
that at least one of the four impedances of the bridge is the discharge
path of the amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 72, | for series energized vacuum tube amplifying devices
with at least two of the devices arranged in the arms of a bridge. |
| 76+, | for amplifiers for compensating for interelectrode
impedance (neutralization) by feedback where the input-output interelectrode
impedance coupling and compensating circuits may be arranged in
a balanced bridge. |
| 81, | for push-pull feedback amplifiers including plural
stages which may have a bridge-like arrangement. |
| 118, | for push-pull vacuum tube amplifiers including those
having plural stages with a bridge-like arrangement. |
| 175, | for interstage coupling circuits including bridge
networks. |
| 273+, | for push-pull semiconductor amplifiers including
those with plural stages presenting a structure similar to a bridge. |
| 293, | and 296, for plural stage semiconductor amplifiers
series energized which may include bridge arrangements. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems,
subclasses 252 , 333, and 365 for various impedance bridge arrangements,
for voltage magnitude or phase control; see also the search notes
under the above subclasses. |
| 333, | Wave Transmission Lines and Networks,
subclass 169 for wave filters having a Wheatstone bridge arrangement.
See also the search notes thereunder. |
|
| | |
| 147 | PLURAL SIGNAL INPUTS: |
| | This subclass is indented under the class definition. Subject matter wherein at least two separate and independent
sources of signal energy are coupled to the input of the amplifying device.
| | (1)
Note. Where each of the separate sources has an amplifying
device in its input circuit before being jointly coupled to an amplifying
device, classification is not herein. |
| | (2)
Note. The two separate sources need not operate to feed signal
energy to the amplifying device simultaneously but may operate selectively,
for example, as by switching the sources whereby one is feeding
the amplifying device at a time. |
| | (3)
Note. A balanced circuit is treated as a single source in
this class. See the definition and notes under subclass 116 above. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers having distributed parameter type
coupling means. |
| 69, | for sum and difference amplifiers. |
| 74, | for series energized vacuum tube amplifiers having
plural separate inputs to series devices. |
| 84, | for signal amplifiers having plural amplifier channels. |
| 124+, | see (1) Note above, also for plural separate inputs
to plural channels. |
| 185+, | for amplifiers having significant input networks. |
| 252+, | for semiconductor amplifiers having plural inputs
or plural channels. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 18+ and 43+ for electrical transmission or interconnection
systems having plural supply circuits or sources. |
|
| | |
| 148 | PLURAL SIGNAL OUTPUTS: |
| | This subclass is indented under the class definition. Subject matter wherein at least two separate signal output
circuits are coupled from the output electrode or element of the
signal amplifying device, for coupling to separate load devices.
| | (1)
Note. Where at least two of the signal output circuits each
contain a signal amplifying device for amplifying the signal, classification
is not herein but with plural signal amplifier channels. |
| | (2)
Note. Any one or more of the separate signal output circuits
may be switched selectively; operation need not be simultaneous
for classification in this subclass. |
| | (3)
Note. A balanced circuit is treated as a single load in this
class. See definition and notes for subclass 117 above. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers having distributed parameter type
coupling means. |
| 73, | for amplifiers having series energized amplifying
devices having plural separate output circuits. |
| 84, | for signal feedback amplifiers having plural amplifier
channels. |
| 124+, | for plural signal amplifier channel, also for separate
outputs from plural channels. see (1) Note above. |
| 192+, | for amplifiers with significant signal output circuit
networks. |
| 252+, | for semiconductor amplifiers with plural separate
signal outputs or plural channels. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 11+ for electric transmission or interconnection systems
having plural load circuit systems. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous circuits
having plural outputs. |
| 329, | Demodulators,
subclasses 316+ for plural outputs in frequency demodulator and
subclass 348 for plural outputs in an amplitude demodulator. |
| 333, | Wave Transmission Lines and Networks,
subclasses 100+ for wave transmission lines and networks having
branched circuits. |
|
| | |
| 149 | HUM OR NOISE OR DISTORTION BUCKING INTRODUCED INTO SIGNAL CHANNEL: |
| | This subclass is indented under the class definition. Subject matter wherein the signal has a hum or noise component
inadvertently introduced therein, as where there is ineffective
filtering of a rectified A.C. power supply or bias, and wherein
such objectional component is removed or reduced by the same hum
or noise component introduced into the signal path of the amplifier
in such manner as to oppose the objectional signal component, thereby
removing it from, or reducing it in, the output signal.
| | (1)
Note. Where such component is removed or reduced by negative
feedback classification is elsewhere. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 75+, | where such components of this subclass (149) are
removed or reduced by negative feedback. See (1) Note above. |
| 114, | for amplifiers having unrectified A.C. power supply
including those with means to eliminate hum. |
| 118+, | for push-pull amplifiers which include means for
opposing noise, hum, or other unwanted components inadvertently
present with the signal, and wherein the compensation is inherent in
the push-pull arrangement, per se. |
| 124+, | for plural channel amplifiers including those wherein
an unwanted component in the signal is separately amplified and
opposes the unwanted component in a channel which includes the signal
and the unwanted component. |
| 150, | for cascaded amplifying devices of different characteristics
including those wherein the characteristics of one stage compensate
for those of another. |
| 151, | for cascaded amplifying devices with means to by-pass
a stage wherein a feed forward component may oppose the same component
in the signal path. |
| 199+, | for amplifiers with power or bias voltage supply
including filters to eliminate hum, etc. |
| 296, | and 297, for semiconductor amplifiers with bias
or power supply circuitry. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 94+ for discharge device load systems having cathode
or cathode heater power supply, with or without anode power supply,
but excluding control electrode supply, including those having means for
hum elimination, etc. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 549 for miscellaneous circuits with power supply and
hum prevention or elimination means. |
| 333, | Wave Transmission Lines and Networks,
subclasses 167+ for wave filters, per se, which may be used to eliminate
a frequency component, particularly subclasses 181+, for smoothing
filters for power supply. |
| 363, | Electric Power Conversion Systems,
subclasses 39+ for electrical conversion systems including means
to eliminate frequency components. |
|
| | |
| 150 | CASCADED SIMILAR AMPLIFYING DEVICE OF DIFFERENT CHARACTERISTICS: |
| | This subclass is indented under the class definition. Subject matter including at least two stages of amplification
(each stage as defined in the class definition and each stage having
a vacuum tube amplifying device) such that, the input signal for
each stage, except the first, is the output signal of the preceding
stage, and wherein at least one of the cascaded amplifying devices
has a significant difference in its characteristics such as a difference
in the number of electrodes, or where the construction of each of at
least two of the tubes is such that there is a difference in the
tube characteristics, or where because of differences in biasing
or energizing voltages the tube characteristics are different.
| | (1)
Note. Different types of vacuum tubes representing a genus
or class and provided for above such as traveling wave tubes and
magnetrons or traveling wave tubes and secondary emission tubes when
claimed in cascade are classified elsewhere (see the search this
class, subclass notes below) Where vacuum tubes, are different
in structural characteristics or some other feature, but all of
the plural tubes fall within one of the genus types provided for
above, as for example traveling wave tubes classification is with
the genus type and not in this subclass. |
| | (2)
Note. Beam power tubes, broadly claimed with no other distinctive
characteristics, when combined in cascade with another vacuum tube
such as an ordinary triode are classified in this subclass and not
in subclass 3 or subclasses 44+ above. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for different types of vacuum tubes representing
a genus or class and provided for above such as traveling wave tubes
and magnetrons or traveling wave tubes and secondary emission tubes
when claimed in cascade. Where vacuum tubes, are different in structural
characteristics or some other feature, but all of the plural tubes
fall within one of the genus types provided for above, as for example
traveling wave tubes classification is with the genus type and not in
this subclass (150) nor in subclass 3. |
| 6, | for magnetrons. |
| 42, | for traveling wave tubes and secondary emission
tubes. |
| 43, | for traveling wave tubes. |
| 70+, | for series arranged vacuum tube amplifiers including
cascaded amplifiers so arranged. |
| 310+, | for cascaded semiconductor amplifiers, particularly
subclass 311 for cascaded semiconductors of different characteristics. |
|
| | |
| 151 | WITH AMPLIFIER BYPASS MEANS (E.G., FORWARD FEED): |
| | This subclass is indented under the class definition. Subject matter wherein means are provided to by-pass all
or a part of the signal across the amplifier or of one or more stages
of a cascade amplifier.
| | (1)
Note. For classification herein the by-pass means must be
free of any amplifying device. Subject matter having such additional
amplifying device is not in this subclass. |
| | (2)
Note. This subclass includes subject matter involving a cascaded
amplifier, for switching an amplifier device in or out of the cascaded
arrangement. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers having distributed parameter coupling
means, particularly subclass 54 for distributed amplifiers. |
| 70+, | for series energized amplifiers including cascaded
amplifiers having such arrangement. |
| 84, | for signal feedback amplifiers having plural amplifier
channels. |
| 88+, | 92, and 98+, for cascaded amplifiers having
signal feedback. |
| 120+, | for cascaded push-pull amplifiers. |
| 124+, | for by-pass means having additional amplifying device.
See (1) Note above. |
| 133, | for cascaded amplifiers having different bias control
for different stages. |
| 145, | for amplifiers having a separately controlled tube
in the signal path. |
| 147, | and 148, for amplifiers having plural signal inputs
and plural signal outputs, respectively. |
| 157, | for amplifier interstage couplings, per se, particularly
subclass 164, for an electronic tube or diode in the coupling circuit. |
| 310+, | for cascaded semiconductor amplifiers. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 100+ for wave transmission passive network branched
circuits. |
|
| | |
| 152 | CASCADED DIFFERENTLY COUPLED BETWEEN STAGES: |
| | This subclass is indented under the class definition. Subject matter including at least three stages of amplification
(each stage as defined in the class definition) such that, the input
signal for each stage, except the first, is the output signal of
the preceding stage; and where two of the interstage coupling means
between successive amplifying devices have different characteristics.
| | (1)
Note. The following are examples of subject matter classified
in this and indented subclasses: one device is coupled from the
plate and the other from the cathode; or one coupling has a tuned circuit
and the other has not; or both couplings have circuits tuned to
different frequencies or the two couplings may be similar but contain
an impedance element or elements of one having different values
from the corresponding element, or elements in the other interstage
coupling. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for plural diverse type amplifying devices. |
| 53+, | for amplifiers having distributed parameter type
coupling. |
| 70+, | for series energized vacuum tube amplifiers. |
| 88, | 92 and 98, for cascaded amplifiers including signal
feedback. |
| 120+, | for interstage coupling between push-pull stages
of an amplifier. |
| 133, | for different bias control on different stages of
a cascaded amplifier. |
| 150, | for cascaded amplifiers with similar amplifying
devices having different characteristics. |
| 151, | for amplifiers with means to by-pass a stage. |
| 157+, | for interstage coupling in an amplifier. |
| 310+, | for plural stage cascaded semiconductor amplifiers. |
SEE OR SEARCH CLASS:
| 323, | Electricity: Power Supply or Regulation Systems, appropriate subclasses for voltage magnitude and
phase control systems generally, with various transformer and impedance
networks to perform such functions. |
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for coupling networks for wave transmission, generally. |
|
| | |
| 153 | Including a cathode follower stage: |
| | This subclass is indented under subclass 152. Subject matter wherein at least one of the interstage coupling
means has a cathode follower signal output.
| | (1)
Note. If only the coupling of the last stage is a cathode
follower and none of the previous stages has a cathode follower
output, classification is not in this subclass. For classification
of cathode follower amplifiers and analogous subject matter see
search notes immediately following. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 119, | for push-pull vacuum tube amplifiers including cathode
followers. |
| 168, | and 172+, for amplifiers having a cathode
follower in the interstage coupling. |
| 193+, | for amplifiers with cathode follower output coupling. |
| 310+, | for cascaded semiconductor amplifiers which may
have an emitter follower stage analogous to cathode follower in
a cascaded vacuum tube amplifier. |
|
| | |
| 154 | Transformer or resonant circuit in interstage coupling
(e.g., stagger tuning) : |
| | This subclass is indented under subclass 152. Subject matter wherein at least one of the interstage coupling
means has a signal coupling transformer or a resonant circuit contained therein.
| | (1)
Note. Stagger tuned amplifiers are classified in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 56, | for amplifiers having wave guide, cavity, or concentric
resonator coupling means. |
| 120, | for interstage coupling between push-pull amplifier
stages including transformer coupling and resonant means in the
coupling circuit. |
| 165+, | for amplifiers having transformer interstage coupling. |
| 302+, | for cascaded semiconductor amplifiers having frequency
responsive signal coupling means. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for wave transmission coupling means, generally, including
resonant circuits and transformer coupling. |
| 334, | Tuners, appropriate subclasses for tuners, per se, and especially
subclasses 59+ and 61+ for transformers used in a resonant
circuit. |
|
| | |
| 155 | UNICONTROL OF COUPLING OR THE CIRCUITS ASSOCIATED THEREWITH: |
| | This subclass is indented under the class definition. Subject matter wherein two or more elements such as resistors,
reactors, etc.., of any coupling network or different coupling networks,
for transmission of the signal in the amplifier are constructed
and arranged so that adjustment or control is simultaneous for such two
or more elements, such adjustment may be for a tuner, a potentiometer,
or any other means or any combination of such means, in the coupling
circuits or associated circuits.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | particularly subclass 56 for distributed parameter
coupling means including adjustment of such means. |
| 65+, | for structure of circuit elements when in an amplifier
which may include the structure of adjustable circuit elements. |
| 108, | for a potentiometer common to the signal and feedback
paths of an amplifier. |
| 116, | and 117, for amplifiers with balanced-to-unbalanced
and unbalanced-to-balanced coupling, respectively, which may involve
adjustable circuit elements. |
| 120, | and 122, for coupling of a push-pull amplifier which
may involve adjustable circuit elements in the coupling. |
| 143, | for amplifiers with a thermally responsive impedance. |
| 144+, | for amplifiers having a variable impedance for the
signal channel controlled by a separate control path. |
| 157+, | for amplifiers with interstage coupling which may
have an adjustable element in the coupling. |
| 171, | 190 and 197, for transformer structure. |
| 185+, | for amplifiers which may have an adjustable element
in the input coupling. |
| 192+, | for amplifiers which may have an adjustable element
in the output coupling. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ , 81 and 219+ for coupling means, attenuators,
or distributed parameter type resonators, respectively, including
those with variable circuit elements. |
| 334, | Tuners, appropriate subclasses for tuners, per se. |
| 336, | Inductor Devices, appropriate subclasses for variable inductor devices. |
| 338, | Electrical Resistors, appropriate subclasses for the structure of rheostats, and
resistors. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 277+ for variable condensers. |
|
| | |
| 156 | BOOTSTRAP COUPLING: |
| | This subclass is indented under the class definition. Subject matter wherein the signal input is floating and
is applied between the control grid and cathode of a vacuum tube
amplifying device, with the cathode having an impedance between
it and ground which maintains the cathode voltage above ground,
by reason of the anode current flowing through such impedance.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for series energized amplifiers including those
having signal coupling between cathode and grid similar to the subject
matter in this subclass. |
| 87+, | for amplifiers having cathode impedance feedback
particularly subclass 89 for cathode coupling between adjacent stages. |
| 119, | for push-pull amplifiers including coupling to the
cathode. |
| 153+, | for amplifiers having interstage coupling to a cathode. |
| 186+, | for amplifiers having input coupling to a cathode. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 589 for miscellaneous electron tube circuits with bootstrap
circuit means. |
|
| | |
| 157 | INTERSTAGE COUPLING: |
| | This subclass is indented under the class definition. Subject matter wherein the amplifier is comprised of at
least two amplifying devices in cascade, the two being in direct
proximity in the cascaded circuit and wherein there are significant
details or distinctive characteristics of the circuit by means of
which the signal output of the preceding amplifying device is coupled to
the signal input of the following cascaded amplifying device, or
wherein the parameters or electrical characteristics of the output
of the preceding device or the input of the following device, are
claimed.
| | (1)
Note. Subject matter disclosing interstage coupling but wherein
only the output coupling of the first amplifying device is claimed
or wherein only the input coupling of the following amplifying device
is claimed is classified in this and appropriate indented subclasses
and not with input or output coupling under subclasses 185+ or
192+, respectively. |
| | (2)
Note. The output of the preceding amplifying device of the
cascaded devices has an output electrode and a common electrode
for the signal and the input of the following stage has an input electrode
and a common electrode, to receive the signal. Thus, there is involved
a four terminal coupling network between output (including common
electrode) and input (including common electrode) with usually two-series
circuits between output and input electrodes and between common
electrodes respectively and also shunt circuit elements often between
such series circuits. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for plural diverse type amplifying devices which
may involve interstage coupling between such devices. |
| 53+, | for coupling of distributed parameter type which
may be interstage. |
| 65+, | for structure of circuit elements, other than transformer
structure, which may be involved in interstage coupling. |
| 70+, | for interstage coupling between cascaded series
energized tubes. |
| 88+, | 92, and 98+, for interstage coupling in cascaded
feedback amplifiers. |
| 120, | for interstage coupling in push-pull amplifiers. |
| 133, | for cascaded amplifiers having bias voltage control
which may involve interstage coupling. |
| 143, | for thermally responsive impedance which may be
involved in interstage coupling. |
| 144+, | for variable impedance controlled by separate control
path which may be involved in interstage coupling. |
| 150, | for cascaded stages having amplifiers of different
characteristics with interstage coupling means. |
| 151, | for cascaded stages with means to by-pass a stage. |
| 152+, | for diverse types interstage coupling in amplifiers
having plural cascaded stages. |
| 155, | for unicontrol of coupling means which may involve
interstage coupling. |
| 156, | for bootstrap coupling. |
| 185+, | for amplifiers with input coupling networks. See
(1) Note above. |
| 192+, | for amplifiers with output coupling networks. See
(1) Note above. |
| 310+, | for plural stage cascaded semiconductor amplifiers,
involving interstage coupling. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ , for passive coupling networks for wave transmission,
generally. |
|
| | |
| 158 | Coupling to cathode: |
| | This subclass is indented under subclass 157. Subject matter wherein the signal derived from the preceding
cascaded amplifying device is coupled to the cathode electrode of
a following cascaded vacuum tube amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 88+, | and 91+, for amplifiers applying signal
feedback to the cathode. |
| 89, | for amplifiers having adjacent cascaded stages with
cathode-cathode coupling. See (1) Note thereunder. |
| 119, | for push-pull amplifiers with coupling to the cathode. |
| 156, | for bootstrap coupling where input signal is applied
directly between grid and cathode. |
| 186+, | for input coupling to the cathode. |
|
| | |
| 159 | D.C. coupling: |
| | This subclass is indented under subclass 158. Subject matter wherein the interstage coupling has a D.C.
conductive path for signal current from the output electrode of
the preceding cascaded amplifying device to the input electrode of
the following device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 187, | for amplifiers with D.C. input coupling to the cathode. |
|
| | |
| 160 | Coupling to plate or auxiliary grid: |
| | This subclass is indented under subclass 157. Subject matter wherein the signal derived from the first
of the two cascaded amplifying devices is coupled to the screen
grid or an electrode other than the control grid or cathode, such
as the anode electrode or the suppressor grid of the following cascaded
amplifying device, which device is of the vacuum tube type.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 64, | for space charge grid tube amplifiers wherein the
first grid next to the cathode is biased positively with respect thereto
and the signal input is applied to the grid next in succession from
the cathode which is biased negatively with respect to the cathode. |
| 185, | and 188+, for input coupling to a vacuum
tube amplifying device including input coupling to an electrode
other than the control grid or cathode. |
SEE OR SEARCH CLASS:
| 324, | Electricity: Measuring and Testing,
subclass 124 for amplifiers combined with an electrical measuring
device wherein the input is applied to the anode of the amplifying
device (e.g., inverted amplifier). |
|
| | |
| 161 | D.C. coupling: |
| | This subclass is indented under subclass 160. Subject matter wherein the coupling has a D.C. conductive
path for signal current from the output electrode of the preceding
amplifying device to the input, electrode of the following of the
two cascaded vacuum tube amplifying devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 191, | for a D.C. amplifier input coupling which may be
to an electrode of a vacuum tube amplifying device other than the
control grid or cathode. |
|
| | |
| 162 | Output coupling from grid: |
| | This subclass is indented under subclass 157. Subject matter wherein the coupling between the two cascaded
amplifying devices is from a grid, such as the screen grid, suppressor
grid or control grid, or from between such a grid and an anode of
the preceding amplifier device (of the vacuum tube type) of the
two cascaded devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 42, | for amplifiers having secondary emission amplifier
devices wherein the output may be from a secondary emissive electrode. |
| 192, | and 195, for output coupling from a grid, such as
the screen grid, suppressor grid or control grid or between such
a grid and the anode. |
SEE OR SEARCH CLASS:
| 324, | Electricity: Measuring and Testing,
subclass 124 for inverter amplifiers combined with measuring
means where the output is from the control grid. |
|
| | |
| 163 | D.C. coupling: |
| | This subclass is indented under subclass 162. Subject matter wherein the coupling has a D.C. conductive
signal path from the grid or from between the grid and anode of
the preceding of the two cascaded amplifying devices (of the vacuum
tube type) to the following device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 198, | for D.C. output coupling which may involve coupling
from a grid or from between a grid and the anode. |
|
| | |
| 164 | With electronic tube or diode in coupling circuit: |
| | This subclass is indented under subclass 157. Subject matter in which the coupling circuit between the
two cascaded stages has at least one path which includes an electronic
discharge tube (which may be a gas tube or vacuum tube having control
means effective during operation of the tube) or which includes a
diode element which may be a glow tube, a rectifier vacuum tube
diode or a dry rectifier diode, etc.
| | (1)
Note. The electronic tube or diode performs some function,
such as an impedance, other than serving as an additional amplifying
device. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 138, | for control of bias or power supply voltage by a
biased rectifier or discharge device. |
| 139, | and 140, for an amplifier including an electronic
tube or rectifier, respectively, to control the input or gain control
electrode bias. |
| 143, | where the diode or electronic tube is a thermally
responsive element. |
| 145, | where the diode or electronic tube is a variable
impedance controlled by a separate control path. |
| 185+, | for amplifier input circuits including any with
an electronic tube or diode, in the input circuit (other than as
a preceding amplifying stage). |
| 192+, | for amplifier output networks which may include
an electronic tube or diode (other than as an amplifying stage). |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 213+ for negative resistance and/or reactance
networks which have an active element including electron tubes or
diodes, as such active elements. |
|
| | |
| 165 | Transformer coupling: |
| | This subclass is indented under subclass 157. Subject matter wherein the the signal coupling between the
two cascaded amplifying device stages is by means of at least one
transformer.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 120, | for interstage coupling in push-pull amplifiers
including transformer coupling. |
| 122, | for input or output coupling in push-pull amplifiers
including transformer coupling. |
| 154, | for transformer coupling in plural stage cascaded
vacuum tube amplifiers with at least two interstage coupling networks
which have some different characteristic. |
| 188+, | for transformer coupled amplifier input circuits. |
| 195+, | for transformer coupled amplifier output circuits. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 177+ for wave transmission transformer coupled circuits
of the passive type, generally. |
| 334, | Tuners,
subclasses 59+ and 61+ for tuners having a transformer
in the resonant circuit. |
| 336, | Inductor Devices, appropriate subclasses, for transformer structure. |
|
| | |
| 166 | With additional reactive coupling: |
| | This subclass is indented under subclass 165. Subject matter wherein, between the primary and secondary
of the transformer, there is an additional capacitive or inductive
reactor element which carries part of the signal current coupled
between the two devices. |
| | |
| 167 | With additional impedance connected to "P" or "S" circuits: |
| | This subclass is indented under subclass 165. Subject matter wherein additional impedance which may be
inductive, capacitive or resistive is included in either the primary
or secondary winding circuit of the transformer which couples the
signal between the two cascaded amplifier devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 189, | for transformer input coupling with additional impedance
connected to the primary or secondary winding circuit. |
| 196, | for transformer output coupling with additional
impedance connected to the primary or secondary winding circuit. |
|
| | |
| 168 | From cathode: |
| | This subclass is indented under subclass 165. Subject matter wherein means are provided to derive the
signal from the cathode of the preceding amplifying device (of the
vacuum tube type).
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for series energized tubes which may have a cathode
follower output. |
| 88+, | and 91, for cascaded amplifiers having signal feedback
to the cathode. |
| 117, | for amplifiers having unbalanced-to-balanced coupling
including phase splitters with cathode coupled output. |
| 119, | for push-pull amplifier involving coupling from
the cathode. |
| 153, | for different interstage coupling in cascaded amplifiers
including a cathode follower stage. |
| 156, | for bootstrap coupled amplifiers. |
| 172+, | for interstage coupling from the cathode for other
than transformer coupling. |
| 193, | for output networks from the cathode of the amplifying
device. |
| 250+, | for semiconductor amplifiers having emitter signal
output analogous to cathode follower output. |
|
| | |
| 169 | With means for adjusting inductive coupling: |
| | This subclass is indented under subclass 165. Subject matter wherein means are provided for adjusting
the inductance of either the primary or secondary winding or the
mutual inductance between the primary and secondary winding, in the
latter case, for example, by varying the position of the primary
or secondary windings or parts thereof relative to each other.
SEE OR SEARCH CLASS:
| 334, | Tuners,
subclasses 61+ for tuners having mutual inductance variable means. |
| 336, | Inductor Devices, appropriate subclasses particularly
subclasses 115+ for adjustable coupling by relatively moving coils,
and subclasses 130+ for relatively movable coil and core
to vary the inductance. Class 336 is the general class for the
structure of inductors including means to vary the inductance and
mutual inductance. |
|
| | |
| 170 | With shielding: |
| | This subclass is indented under subclass 165. Subject matter combined with shielding means, for the transformer,
or parts thereof.
| | (1)
Note. Under interstage coupling, shielding and the structure
of shielding are classified separately (subclass 170) from other
structure of transformers (subclass 171). Under input and output
coupling no separate provision is made for shielding so that all
structure of transformers in input or output amplifier coupling including
shielding is classified in subclasses 190 and 197, below respectively. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 68, | for shielding combined with amplifiers or with circuit
elements of amplifiers, generally. |
| 190, | for amplifier input coupling including transformer
structure which may include shielding. |
| 197, | for amplifier output coupling including transformer
structure which may include shielding. |
SEE OR SEARCH CLASS:
| 174, | Electricity: Conductors and Insulators,
subclasses 350 through 397, shielded or screened, for shielding electrical
elements, generally. See the search notes thereunder. |
| 336, | Inductor Devices,
subclasses 84+ for shielding of inductors, generally. See the
search notes thereunder. |
|
| | |
| 171 | With transformer structure: |
| | This subclass is indented under subclass 165. Subject matter involving the structure of the transformer
coupling the signal between the two cascaded stages.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 65+, | for structure of amplifier circuit elements other
than transformers involved with an amplifier system. |
| 190, | for the structure of transformers in amplifier input
coupling. |
| 197, | for the structure of transformers in amplifier output
coupling. |
SEE OR SEARCH CLASS:
| 336, | Inductor Devices, appropriate subclasses for transformer structure
generally. |
|
| | |
| 172 | Coupling from cathode: |
| | This subclass is indented under subclass 157. Subject matter wherein the signal output is coupled form
the cathode electrode of the preceding vacuum tube amplifier device
of the two cascaded amplifying devices, to the input of the following
amplifier device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for series energized vacuum tube amplifiers which
may have an output circuit from the cathode. |
| 88, | and 91, for cascaded vacuum tube amplifying devices
with signal feedback from the cathode. |
| 89, | for amplifiers having adjacent cascaded stages with
cathode-cathode coupling. |
| 117, | for amplifiers with unbalanced-to-balanced coupling
including phase splitters with cathode output coupling. |
| 119, | for push-pull amplifiers with coupling from the
cathode. |
| 153, | for plural stage cascaded vacuum tube amplifying
devices with different coupling between stages including a cathode
follower stage. |
| 156, | for bootstrap coupling. |
| 168, | for interstage transformer coupling from the cathode. |
| 193+, | for amplifier output coupling networks from the
cathode of the amplifying device (cathode followers) see the notes
and search notes thereunder. |
| 250+, | for semiconductor amplifiers having emitter output
analogous to cathode follower output. |
|
| | |
| 173 | D.C. coupling: |
| | This subclass is indented under subclass 172. Subject matter wherein the coupling between the two cascaded
amplifying devices is a D.C. conductive path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 194, | for vacuum tube amplifier device output coupling
circuits with D.C. coupling from the cathode. |
|
| | |
| 174 | With electromechanical transducer (e.g., piezoelectric
crystal): |
| | This subclass is indented under subclass 157. Subject matter wherein the coupling circuit between the
two cascaded amplifier devices includes means to convert the electric
signal to mechanical vibrations and means further to convert the
mechanical vibrations back to electric signals, such means, generally,
serving as either time or phase delay means or means to determine
the transmission frequency of the coupling network.
| | (1)
Note. The electromechanical transducer means in this subclass
is distinguished from subject matter of subclass 60 above, wherein
the amplifying device itself includes a magnetostrictive means electromechanical
transducer. In this subclass, the electrical signal energy is not
used to control another source of electrical energy applied to the
transducer, but herein the electric signal, in being transmitted,
is converted to mechanical energy and back to electrical energy. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 60, | for amplifiers having magnetostrictive means. |
| 185+, | for amplifier input circuits including any having
an electromechanical transducer. See (1) Note under subclass 157. |
| 192, | for amplifier output circuits including any having
an electromechanical transducer. See (1) Note under subclass 157. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 148+ , 186, and 187+ for delay lines using electromechanical
transducers, and for wave filters using electromechanical transducers
and piezo-electric types of such transducers, respectively. See the
search notes under these subclasses. |
|
| | |
| 175 | With lattice or Wheatstone bridge network in coupling circuits: |
| | This subclass is indented under subclass 157. Subject matter wherein the coupling includes a network having
four impedance branches connected in series to form a closed circuit,
two nonadjacent junction points serving as input terminals while
the remaining two junction points serve as output terminals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 72, | for plural amplifier devices having space discharge
paths in different arms of a bridge. |
| 146, | for Wheatstone bridge with amplifier in at least
one arm. |
| 185+, | for amplifier input coupling including any with
a lattice or Wheatstone bridge network. See (1) Note under subclass
157, above. |
| 192+, | for amplifier output coupling including any with
a lattice or Wheatstone bridge network. See (1) Note under subclass
157, above. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclass 74 , sections (1) and (2) of the definition. |
|
| | |
| 176 | With T, H, or Pi network in coupling circuit: |
| | This subclass is indented under subclass 157. Subject matter wherein the coupling includes a T, H, or
Pi circuit network.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 185+, | for amplifier input circuit networks including any
with a T, H, or Pi circuit network. See (1) Note under subclass 157,
above. |
| 192+, | for amplifier output circuit networks including
any with a T, H, or Pi circuit network. See (1) Note under subclass 157,
above. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ , appropriate subclasses thereunder for coupling circuits
which may include T, H, of Pi networks. See the notes and search notes
under Class 333, subclass 24. |
|
| | |
| 177 | With coupling or blocking capacitor: |
| | This subclass is indented under subclass 157. Subject matter wherein any path traced in series from the
output electrode of the preceding of the two cascaded amplifying
devices to the input electrode of the amplifier device of the following
stage contains at least one capacitor.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 120, | for push-pull amplifiers with significant interstage
coupling which may include a blocking capacitor in such coupling. |
| 166, | for amplifiers with interstage transformer coupling
having additional reactive coupling which may be a capacitor. |
| 185, | and 186, for amplifier capacitor input coupling,
generally, and to a cathode, respectively. |
| 192, | and 193, for amplifier capacitor output coupling,
generally, and from a cathode, respectively. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for coupling circuits generally, see notes and search
notes under subclass 24. |
|
| | |
| 178 | With R or L in series between stages: |
| | This subclass is indented under subclass 177. Subject matter wherein the series path between the output
electrode of the preceding of the two cascaded devices and the input
electrode of the succeeding device has a resistor of inductance in
such path in series with the coupling or blocking capacitor. |
| | |
| 179 | L in anode or grid circuit: |
| | This subclass is indented under subclass 177. Subject matter having in addition an inductor connected
to the anode output electrode of the preceding stage device or to
the grid input electrode of the following stage device, in shunt across
the signal transmission path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | appropriate subclasses for circuits in the anode
power supply or grid bias supply which may include an inductor.
See the search notes under subclass 199, below. |
|
| | |
| 180 | With R in anode and grid circuit (RC coupling): |
| | This subclass is indented under subclass 177. Subject matter having in addition a resistance directly
connected to the anode output electrode from the anode power supply
of the preceding amplifier stage device and a resistance directly
connected to the input grid electrode of the following amplifier
stage device from the negative bias source or ground, each resistance being
in shunt across the signal transmission path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | for power or voltage supply circuits to the anode
or grid electrodes which may have resistors therein. See the search
notes under subclass 199, below. |
|
| | |
| 181 | D.C. coupled: |
| | This subclass is indented under subclass 157. Subject matter wherein the series coupling from the output
electrode of the preceding amplifier device to the input electrode
of the following amplifier device of the two cascaded stages has
a D.C. conductive path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for periodic switching for input-output comparison
including drift corrected D.C. amplifiers. |
| 10, | for modulator-demodulator amplifiers for amplifying
D.C. signals. |
| 53+, | for amplifiers having distributed parameter coupling
which may include D.C. interstage coupling. |
| 70+, | for series energized amplifiers. |
| 121, | for push-pull amplifiers having D.C. interstage
coupling. |
| 125, | for plural amplifier channels involving a D.C. and
an A.C. channel. |
| 159, | for interstage D.C. coupling to the cathode. |
| 161, | for D.C. interstage coupling to the screen grid
or electrode other than control grid or cathode. |
| 163, | for D.C. interstage output coupling from a grid
or between a grid and the anode. |
| 173, | for D.C. interstage coupling from the cathode. |
| 187, | for input D.C. coupling to the cathode. |
| 191, | for D.C. input coupling, generally. |
| 194, | for D.C. output coupling from the cathode. |
| 198, | for D.C. output coupling, generally. |
| 289, | for D.C. conductively coupled cascaded semiconductor
amplifiers. |
| 293, | and 296, for series energized cascaded semiconductor
amplifiers. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for wave transmission coupling, generally. See, also,
search notes under subclass 24. |
|
| | |
| 182 | With series reactive element between stages: |
| | This subclass is indented under subclass 181. Subject matter wherein the series coupling D.C. conductive
path between the output electrode of the preceding amplifying device
and the input electrode of the following amplifying device contains
therein a reactive element, such as an inductor or parallel to a
D.C. conductive element in the series path there is a capacitive
reactive element.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers with distributed parameter coupling
which may involve a D.C. conductive path including a reactive element. |
| 107, | for signal feedback amplifiers having a phase shift
network in the loop path. |
| 121, | for push-pull amplifiers having D.C. interstage
coupling including any with series reactor element. |
| 143, | for amplifiers having a thermally responsive impedance. |
| 144+, | for amplifiers having a variable impedance in the
signal path controlled by a separate control path. |
| 166, | for transformer coupled amplifier stages including
a D.C. reactive element (inductor coil) jointing the primary and
secondary windings. |
| 175, | for amplifiers having a lattice or Wheatstone bridge
network in the interstage coupling circuit. |
| 176, | for amplifiers having a T, H, or Pi network in the
interstage coupling. |
| 302+, | for semiconductor amplifiers having frequency responsive
means in the signal transmission path. |
|
| | |
| 183 | With nonlinear device: |
| | This subclass is indented under subclass 181. Subject matter wherein the coupling contains a device whose
impedance (which may be resistive, capacitive, or inductive or any
combination of these) is such that the relationship of voltage across
the device to the current flow therein is nonlinear.
| | (1)
Note. The device may be in shunt across the signal transmission
path, or in the D.C. series path between the vacuum tube amplifying
devices, or in any other position in the signal coupling circuit. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 86, | for signal amplifiers with a variable impedance
in the feedback path which is varied by a separate control path. |
| 95, | for feedback amplifiers having a nonlinear impedance
means in the cathode circuit. |
| 110, | for feedback amplifiers having a nonlinear impedance
element in the loop path. |
| 127+, | for nonlinear impedances involved in circuits for
the control of amplifier power supply or bias voltage. |
| 143, | for amplifiers having a thermally responsive impedance. |
| 144+, | for amplifiers having a variable impedance for the
signal channel which is varied by a separate control path. |
| 164, | for cascaded amplifiers having an electronic tube
or diode in an interstage coupling circuit. |
| 174, | for cascaded amplifiers having an electromechanical
transducer such as a piezo-electric crystal in an interstage coupling
circuit. |
| 185, | or appropriate indented subclass for a nonlinear
device involved in the input coupling. |
| 192, | or appropriate indented subclass for a nonlinear
device involved in the output coupling. |
| 299+, | for semiconductor amplifiers having a diverse type
semiconductor, which may be a nonlinear coupling impedance. |
SEE OR SEARCH CLASS:
| 257, | Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for active solid-state devices, per se, including
subclasses 115 , 123 and 162 through 166 which are directed to
devices involving amplification. |
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 401+ for nonlinear reactor systems. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous nonlinear
transistor and electron tube circuits. |
| 333, | Wave Transmission Lines and Networks, appropriate subclasses for wave transmission networks
which may involve nonlinear impedance elements. |
| 338, | Electrical Resistors,
subclasses 13+ for nonlinear resistor elements. |
| 361, | Electricity: Electrical Systems and Devices,
subclasses 271+ for structure of a capacitor which may be nonlinear. |
|
| | |
| 184 | With series resistance between stages: |
| | This subclass is indented under subclass 181. Subject matter wherein the series coupling D.C. conductive
path between the output electrode of the preceding amplifying device
and the input electrode of the following amplifying device of the
two cascaded amplifying devices contains therein a resistor. |
| | |
| 185 | INPUT NETWORKS: |
| | This subclass is indented under the class definition. Subject matter involving significant detail or distinctive
characteristics of the electrical circuit coupling a source of signal
energy to the input of the amplifying device; or involving electrical
characteristics of the source; or involving input electrical parameters
of the amplifying device to which the signal input is coupled.
| | (1)
Note. Subject matter in which a source is claimed by name
only as a specific art device, as for example, a microphone, is classified
with specific art device and not with amplifiers. Subject matter
in which the source device may be broadly claimed, not by name,
but by some distinctive identifying feature thereof, as where the
microphone source is claimed as a "means for converting
sound signals", classification is not with amplifiers but
with the distinctive art device. |
| | (2)
Note. The term "generator" or "oscillator" in
claims, where either appears as a source of signal energy without
further qualification except an electrical characteristic such as
impedance, reactance etc., is treated as a generalized source of signal
energy, and classification is with amplifiers. Where specific details
of the generator or oscillator are claimed, classification is with
the type of generator established in the claims or with oscillators
in Class 331, Oscillators. |
| | (3)
Note. Amplifier subject matter disclosing an interstage coupling
but wherein only the input coupling to the succeeding stage is claimed
and no interstage coupling or details to establish such coupling
are claimed, is not classified in this and indented subclasses.
See the search this class, subclass notes below for Interstage Coupling. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 65+, | for input coupling involving structure of any of
the input circuit elements. |
| 74, | for plural inputs to series energized tubes. |
| 106, | for amplifiers having feedback in series with the
input source. |
| 108, | for input coupling which may include a potentiometer
therein common to the signal and feedback paths. |
| 116, | for amplifiers with balanced input involved in balanced-to-unbalanced circuits. |
| 117, | for amplifiers with unbalanced input involved in
unbalanced-to-balanced circuits. |
| 122, | for push-pull amplifiers with significant input
coupling. |
| 143, | for amplifiers having thermally responsive impedance
which may be in the input coupling. |
| 144, | for amplifiers with variable impedance controlled
by separate control path which may be in the input coupling. |
| 147, | for plural signal inputs. |
| 157+, | appropriate subclasses for input coupling involved
in interstage coupling particularly subclasses 158+ and 160+.
See (3) Note under this subclass above. |
| 192, | for output coupling networks. |
| 252+, | for semiconductor amplifiers with plural inputs. |
| 275, | and 301, for semiconductor amplifier devices having
balanced coupling. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for passive coupling networks for wave transmission
generally. |
| 338, | Electrical Resistors, appropriate subclasses for the structure of rheostats
or resistors which may be used in input coupling. |
|
| | |
| 186 | To cathode : |
| | This subclass is indented under subclass 185. Subject matter wherein the input signal is coupled to the
cathode of a vacuum tube amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 88+, | and 91+, for signal feedback to a cathode
circuit, particularly subclass 89 for cathode-cathode coupling between adjacent
stages. |
| 119, | for push-pull amplifiers involving coupling to the
cathode. |
| 156, | involving coupling directly between cathode and
grid. |
| 158+, | for interstage coupling to the cathode. |
| 250+, | for subject matter including semiconductor device
input coupling to emitter, which may be the dual or analogue of
an input coupling circuit to the cathode electrode of a vacuum tube
amplifying device. |
|
| | |
| 187 | D.C. coupled: |
| | This subclass is indented under subclass 186. Subject matter wherein the input coupling network has a
D.C. conductive path from the source of signal energy to the cathode
input electrode of the amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 159, | for D.C. interstage coupling to the cathode of a
vacuum tube amplifying device. |
|
| | |
| 188 | Transformer coupled: |
| | This subclass is indented under subclass 185. Subject matter in which the input circuit includes a transformer
which couples the signal energy from the signal source to the amplifier device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 120, | for interstage coupling between push-pull stages
which may involve transformer coupling. |
| 122, | for input coupling for push-pull amplifiers which
may involve transformer coupling. |
| 154, | for transformer coupling which may be involved in
a cascaded amplifier with different interstage couplings. |
| 165+, | involving interstage transformer coupling. |
| 195+, | for output transformer coupling. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 177+ for passive wave transmission transformer coupling
circuits generally. |
|
| | |
| 189 | With additional impedance connected to "P" or "S" circuits: |
| | This subclass is indented under subclass 188. Subject matter wherein additional impedance which may be
capacitive, inductive, or resistive is included in either the primary
or secondary winding circuit of the input coupling transformer.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 167, | for interstage transformer coupling, with additional
impedance in the primary or secondary winding circuit. |
| 195+, | for output transformer coupling including additional
impedance in the primary or secondary winding of the transformer
coupling network. |
|
| | |
| 190 | With transformer structure: |
| | This subclass is indented under subclass 188. Subject matter involving the structure of the transformer
in the input coupling circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 65+, | for structure of amplifier system elements other
than that of the transformer. |
| 170, | for interstage transformer coupling with shielding. |
| 171, | for interstage transformer structure. |
| 197, | for structure of the transformer in the output coupling. |
SEE OR SEARCH CLASS:
| 336, | Inductor Devices, appropriate subclasses for transformer structure,
per se. |
|
| | |
| 191 | D.C. coupled: |
| | This subclass is indented under subclass 185. Subject matter wherein the input coupling circuit has a
D.C. conductive path from the signal input source to the signal
input electrode of the amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for periodic switching for input-output comparison
including drift corrected D.C. amplifiers. |
| 10, | for modulator-demodulator amplifiers for amplifying
D.C. signals. |
| 53+, | for amplifiers having distributed parameter coupling
means which may have a D.C. conductive path. |
| 125, | for plural amplifier channels involving a D.C. and
an A.C. amplifier channel. |
| 159, | for interstage D.C. coupling to cathode. |
| 161, | for interstage D.C. coupling to screen grid or electrode
other than control grid or cathode. |
| 163, | for D.C. interstage coupling from grid or between
grid and anode. |
| 173, | for D.C. interstage coupling from cathode. |
| 181+, | for D.C. interstage coupling. |
| 187, | for cathode input D.C. coupling. |
| 194, | for D.C. coupling from cathode. |
| 198, | for D.C. output coupling. |
|
| | |
| 192 | OUTPUT NETWORKS: |
| | This subclass is indented under the class definition. Subject matter involving significant detail or distinctive
characteristics of the electrical circuit coupling the output signal
from the amplifying device to a load for utilizing such signal;
or involving electrical characteristics or vacuum tube parameters
such as output impedance of the amplifying device or impedance of
the load involved in such coupling.
| | (1)
Note. Where the load is claimed, even broadly, or by name
only as a specific electrical art device, as for example, as a loudspeaker,
classification is not in this class, but with the load art device claimed.
Where characteristics of the load device are claimed, which are
peculiar to the disclosed electrical art device or to a specific
type of electrical art device, classification is with the load art device
established in the claim. |
| | (2)
Note. Subject matter wherein general electrical characteristics
of the load are claimed, as for example, "a load having a
variable impedance", is classified in this or indented
subclasses. |
| | (3)
Note. Subject matter disclosing an interstage coupling and
where only the output coupling of a preceding stage is claimed, is
not classified in this and indented subclasses, although the coupling
is claimed to establish an output coupling or claimed as an output
coupling. |
| | (4)
Note. Subject matter wherein an amplifier combined with an
oscillator as load for the amplifier are classified with amplifiers
when the oscillator is claimed by name only. Where specific details
of the oscillator are claimed classification is elsewhere. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for distributed parameter type output coupling. |
| 65+, | for output coupling involving structure of any of
the output network circuit elements. |
| 73, | for plural outputs from series energized tubes. |
| 105, | for output coupling involving feedback from an impedance
in series with the output load. |
| 108, | for output coupling including a potentiometer therein
common to the signal and feedback paths. |
| 116, | for unbalanced output coupling in amplifiers having
balanced-unbalanced coupling. |
| 117, | for balanced output coupling in amplifiers having
unbalanced-balanced coupling. |
| 122, | for output coupling from a push-pull amplifier. |
| 143, | for thermally responsive impedance which may be
in the output coupling. |
| 144+, | for variable impedance which may be in the output
coupling. |
| 157+, | for interstage coupling involving coupling from
the output of an amplifier device particularly subclasses 162+ for
output coupling from grid or between grid and anode, subclass 168 for
transformer coupling from cathode, 172+ for other interstage
coupling from the cathode. |
| 185, | for input coupling networks for amplifiers. |
| 252+, | for semiconductor amplifiers having plural outputs. |
| 275, | and 301, for semiconductor amplifiers having either
balanced or unbalanced output. |
SEE OR SEARCH CLASS:
| 331, | Oscillators, where specific details of the oscillator are claimed. |
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for passive coupling networks for wave transmission
in general. |
|
| | |
| 193 | From cathode: |
| | This subclass is indented under subclass 192. Subject matter, wherein the output signal is coupled from
the cathode electrode of a vacuum tube amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for series energized vacuum tube amplifiers which
may have the output coupled from the cathode of a vacuum tube amplifying
device. |
| 88+, | and 91, for signal feedback coupled from the cathode
particularly subclass 89 for cathode-cathode coupling of adjacent
stages. |
| 117, | for unbalanced-to-balanced coupling including phase
splitters having cathode coupled output. |
| 119, | for push-pull amplifiers involving coupling from
the cathode. |
| 153, | for cascaded amplifiers having plural interstage
couplings of different characteristics. |
| 156, | for bootstrap coupling. |
| 168, | for transformer interstage coupling from the cathode. |
| 172+, | for interstage coupling from the cathode. |
| 250+, | for semiconductor device emitter follower circuits,
analogous to cathode follower circuits. |
| 293, | and 296, for series energized cascaded semiconductor
amplifier devices which may have the output coupled from an emitter
electrode of a transistor. |
|
| | |
| 194 | D.C. coupled: |
| | This subclass is indented under subclass 193. Subject matter in which the output coupling network has
a D.C. conductive path from the cathode to the load.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 173, | for D.C. coupling from the cathode involved in interstage
coupling. |
|
| | |
| 195 | Transformer coupled: |
| | This subclass is indented under subclass 192. Subject matter in which the output circuit network includes
a transformer for coupling the signal from the amplifier device
to the load.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 120, | and 122, for push-pull amplifiers which may involve
transformer output coupling. |
| 154, | for transformer coupling involved in plural diverse
stages of a cascaded amplifier. |
| 165+, | involving interstage transformer coupling. |
| 188+, | for input transformer coupling. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclasses 177+ for wave transmission transformer coupling circuits
in general. |
| 334, | Tuners,
subclasses 59+ and 61+ for tuners having a transformer
in the resonant circuit. |
|
| | |
| 196 | With additional impedance connected to "P" or "S" circuit: |
| | This subclass is indented under subclass 195. Subject matter where additional impedance which may be capacitive,
inductive, or resistive is included in the primary or secondary
winding circuit of the output coupling transformer.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 167, | for interstage transformer coupling with additional
impedance in the primary or secondary winding circuit. |
| 189, | for input transformer coupling with additional impedance
connected in the primary or secondary winding circuit. |
|
| | |
| 197 | With transformer structure: |
| | This subclass is indented under subclass 195. Subject matter involving the structure of the transformer
in the output coupling circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 65+, | for structure of amplifier system elements other
than that of the transformer. |
| 170, | for interstage transformer coupling with shielding. |
| 171, | for interstage transformer structure. |
| 190, | for input transformer structure. |
SEE OR SEARCH CLASS:
| 336, | Inductor Devices, appropriate subclasses for transformer structure,
per se. |
|
| | |
| 198 | D.C. coupled: |
| | This subclass is indented under subclass 192. Subject matter wherein the output coupling network has a
D.C. conductive path from the output electrode of the amplifying
device to the load.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for periodic switching for input-output comparison
including drift corrected D.C. amplifiers. |
| 10, | for modulator-demodulator amplifiers for amplifying
D.C. signals. |
| 53+, | for amplifiers having distributed parameter coupling
means which may have a D.C. conductive path. |
| 125, | for plural amplifier channels involving a D.C. and
an A.C. amplifier channel. |
| 159, | for interstage D.C. coupling to cathode. |
| 161, | for interstage D.C. coupling to screen grid or electrode
other than control grid or cathode. |
| 163, | for D.C. interstage coupling from grid or between
grid and anode. |
| 173, | for D.C. interstage coupling from cathode. |
| 181+, | for D.C. interstage coupling. |
| 187, | for cathode input D.C. coupling. |
| 191, | for D.C. input coupling. |
| 194, | for D.C. coupling from cathode. |
|
| | |
| 199 | WITH POWER OR BIAS VOLTAGE SUPPLY: |
| | This subclass is indented under the class definition. Subject matter in which the "source of electrical
energy" controlled by the signal input; or biasing means
applied to the "amplifying device", or the means
to apply such energy or bias, such as the circuits through which
such source or bias is applied; or means for isolating such source
or biasing means from the signal path or other amplifier circuits
(by filters, isolating resistors, or other means), is significantly
claimed, and which subject matter is not provided for in any of
the previous subclasses.
| | (1)
Note. Merely claiming power supply source or biasing means
by name only or broadly without significant detail or distinctive
characteristics is insufficient for classification in this and indented
subclasses. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4, | for maser type amplifying devices. |
| 5, | for solid element wave propagating amplifying devices. |
| 6, | for Hall effect type means. |
| 7, | for capacitive amplifying devices. |
| 8, | for saturable reactor type amplifying devices. |
| 41, | for gas or vapor tube amplifying devices. |
| 42, | for secondary electron emission tube amplifying
device. |
| 43, | for traveling wave type tube. |
| 44+, | for electron beam tube amplifying device. |
| 47+, | for magnetically influenced discharge devices, (e.g.,
magnetrons). |
| 49, | for vacuum tube having distributed parameter impedance
characteristics. |
| 58, | for rotating dynamoelectric amplifying devices. |
| 60, | for magnetostrictive type amplifying devices. |
| 61+, | for restrictive and magnetoresistive type amplifying
devices. |
| 63, | for significant power supply or biasing means combined
with an amplifying device and magnetic means which controls the
energy of said power supply or biasing means, or when a magnetic
means is involved in some other manner in the structure of an amplifying
device combined with significant power supply or biasing means. |
| 64, | for space charge grid tubes biased to operate as
such. |
| 70+, | for series energized vacuum tube amplifiers and
18 for series energized semiconductor amplifiers. |
| 113, | for polyphase power supply. |
| 114+, | for unrectified A.C. power supply. |
| 123, | for amplifiers including a push-pull stage having
significant bias or power supply means. |
| 127+, | for amplifiers with means to control the bias or
power supply voltage. |
| 142, | for cathode self-biasing circuits. |
| 149, | for hum elimination by introduction of the hum component
in the signal path in opposed phase. |
| 296, | and 297, for semi-conductor type amplifying devices
when combined with significant power supply or bias means or involving
related circuitry. |
SEE OR SEARCH CLASS:
| 307, | Electrical Transmission or Interconnection Systems,
subclasses 149+ for miscellaneous "power pack"" systems. |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 91+ for cathode or cathode heater including anode supply
circuit but not including any grid biasing circuit. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 530+ for miscellaneous circuits combined with power
supply or bias means. |
| 329, | Demodulators, appropriate subclasses for demodulators with particular
power supply. |
| 359, | Optical: Systems and Elements,
subclasses 333+ for laser amplifiers. |
|
| | |
| 200 | For plural stage amplifier: |
| | This subclass is indented under subclass 199. Subject matter where the power supply or bias means is for
an amplifier comprising two or more stages of amplification.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for plural diverse type amplifying devices which
may involve power supply or bias means. |
| 88+, | 92, and 98+, for cascaded signal feedback
amplifiers which may involve power supply or bias means. |
| 123, | for push-pull amplifiers, which may be cascaded,
having significant bias or power supply means. |
| 124, | for plural amplifier channels which may involve
cascaded amplifiers having significant power or bias supply means. |
| 133, | for different bias controls for different stages
of a cascaded amplifier. |
| 150, | for cascaded amplifiers with different characteristics
which may be different bias means or voltages. |
| 152+, | for cascaded amplifiers, differently coupled between
stages, which may involve circuitry for the bias or power supply
means also. |
| 157+, | for amplifiers with interstage coupling circuits
which may involve circuitry for the bias or power supply means also. |
| 296+, | for plural stage semiconductor amplifiers involving
bias or power supply circuitry. |
|
| | |
| 201 | Filamentary cathodes heated by anode current or anode supply
source: |
| | This subclass is indented under subclass 200. Subject matter where the filamentary cathodes of at least
one vacuum tube amplifying device of the plural stage amplifier
derives its electrical heating supply either from the anode or anode
power supply of one vacuum tube amplifying device stage of the plural
stage amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 115, | for amplifiers having unrectified A.C. power supplied
to a filamentary cathode (directly heated type). |
| 205, | for similar subject matter for a filamentary cathode
also involving power supply or bias means for an input electrode. |
| 206, | for power supply or bias means applied to a filamentary
cathode (directly heated type), generally. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 94+ for power supply or power supply circuit for cathode
filament or cathode heater circuit with or without anode supply but
not including grid biasing supply. |
|
| | |
| 202 | For anode: |
| | This subclass is indented under subclass 199. Subject matter wherein the "source of electrical energy",
biasing means, the circuit or means for supplying such electrical
energy or bias voltage, or isolating means for such source or bias
means supplies the anode of a vacuum tube amplifying device or isolates
such supply for the anode from other parts of the amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 70+, | for series energized amplifiers. |
| 128, | for control of bias or power supply voltage with
control means in anode or screen grid circuit. |
| 157+, | 185+ and 192+, appropriate subclasses
thereunder for impedances from the power source to anode involved
in interstage, input, and output coupling respectively. |
| 293+, | for series energized semiconductor amplifying devices. |
|
| | |
| 203 | And input electrode: |
| | This subclass is indented under subclass 202. Subject matter where additional bias supply or isolating
means are furnished for an input electrode of an amplifying device.
| | (1)
Note. Input electrode refers to any electrode to which the
electrical signal input is applied, usually the control grid physically
next to the cathode, and the cathode which is, usually, also common
to the input and output circuits of the amplifier, the anode being
an output electrode. |
| | (2)
Note. Cathode self-biasing circuits where the bias is established
by the flow of plate current through the cathode impedance are not
classified herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 142, | for cathode self-biasing circuits where the bias
is established by the flow of plate current through the cathode impedance. |
|
| | |
| 204 | For input electrode: |
| | This subclass is indented under subclass 199. Subject matter wherein the bias supply or isolating means
is furnished to or for an input electrode of a vacuum tube amplifying
device.
| | (1)
Note. Input electrode refers to any electrode to which the
electrical signal input is applied, usually the control grid physically
next to the cathode and the cathode which is usually, also common
to the input and output circuits of the amplifier, the anode being
an output electrode. In grounded grid amplifiers the relationship of
cathode and anode as described above is, of course, usually reversed. |
| | (2)
Note. Cathode self-biasing circuits where the bias is established
by the flow of plate current through the cathode impedance are not
classified herein. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 142, | for cathode self-biasing circuits where the bias
is established by the flow of plate current through the cathode impedance. |
| 157+, | 185+ and 192+, for impedances
in the input electrode bias circuit involved in interstage, input,
or output coupling, respectively. |
|
| | |
| 205 | And filamentary cathode: |
| | This subclass is indented under subclass 204. Subject matter wherein power supply, bias means or isolating
means are supplied to the filamentary cathode of the vacuum tube
amplifying device, as input electrode; and/or as cathode
heating electrical current supply to the directly heated filamentary
cathode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 115, | for amplifiers having unrectified A.C. power supplied
to a filamentary cathode. |
| 127, | for control of emission of a cathode electrode. |
| 201, | for power supply bias means for cathode filaments
in a plural stage amplifier heated by the anode current or by current
from the anode supply source. |
| 206, | for power supply for a filamentary cathode generally. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 94+ for power supply or power supply circuit for cathode
filament or cathode heater circuit with or without anode supply but
not including grid biasing supply. |
|
| | |
| 206 | For filamentary cathode: |
| | This subclass is indented under subclass 199. Subject matter which may include the heater current supply
for a filamentary cathode of a vacuum tube amplifying device not
classified in any preceding subclass.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 115, | for amplifiers having unrectified A.C. power supplied
to a filamentary cathode. |
| 127, | for control of emission of a cathode electrode. |
| 201, | for power supply bias means for cathode filaments
in a plural stage amplifier heated by the anode current or by current
from the anode supply source. |
| 205, | for similar subject matter for a filamentary cathode
also involving power supply or bias means for an input electrode. |
SEE OR SEARCH CLASS:
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 94+ for power supply or power supply circuit for cathode
filament or cathode heater circuit with or without anode supply but
not including grid biasing supply. |
|
| | |
| 207 | MISCELLANEOUS: |
| | This subclass is indented under the class definition. Subject matter not provided for in any of the subclasses
above. |
| | |
| 250 | WITH SEMICONDUCTOR AMPLIFYING DEVICE (E.G., TRANSISTOR): |
| | This subclass is indented under the class definition. Subject matter in which the amplifying device is a semiconductor.
| | (1)
Note. Semiconductors are those materials which have a specific
resistance, for example, of the order of that of germanium, silicon,
selenium, etc. Subject matter including insulators which are in operation
reduced to specific resistance values of the aforesaid range, by
alpha or electron bombardment, heat or other means so they act
in the circuit, broadly, as semiconductors, are classified in this or
appropriate indented subclasses. |
| | (2)
Note. For specific types of amplifier devices in amplifiers,
which may include a semiconductor material, see the pertinent subclass
for the particular semiconductor device involved in this class. |
| | (3)
Note. For vacuum tube amplifier device, amplifier circuits
similar or related to semiconductor amplifier device circuits, see
below the appropriate subclass and indented subclasses for such
circuit. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for combined plural diverse amplifying-type devices,
where one of the amplifying devices is of the semiconductor type. |
| 4, | for master-type amplifying devices wherein the master
excited substance is a semiconductor. |
| 4.9, | for parametric semiconductor amplifiers. |
| 5, | for solid element wave propagating amplifying devices
wherein the solid element is a semiconductor. |
| 6, | for Hall effect-type semiconductor amplifying devices
wherein the Hall effect material is a semiconductor. |
| 7, | for capacitive amplifying devices, some of which
may have semiconductor properties. |
| 9, | for amplifier systems with periodic switching input-output
comparison of signal which may have a semiconductor amplifying device. |
| 10, | for modulator-demodulator amplifier systems which
may have semiconductor amplifier devices. |
| 11, | for amplifiers having D.C. reinsertion circuits
which may include a semiconductor amplifying device. |
SEE OR SEARCH CLASS:
| 257, | Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses integrated circuit structure with
active solid-state devices, especially
subclasses 115 , 123, and 157 through 161 for regenerative type
devices with amplification means, and subclasses 446 and 499+ for
integrated circuit devices with electrically isolated components. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for miscellaneous nonlinear
conductor device (e.g., transistor) circuits. See search notes. |
| 329, | Demodulators, appropriate subclasses for demodulators utilizing transistor
elements. |
| 361, | Electricity: Electrical Systems and Devices, for transistor circuits with electric relays or
electromagnetic loads. |
| 438, | Semiconductor Device Manufacturing: Process, appropriate subclass for methods of making semiconductor electrical
devices. |
|
| | |
| 251 | Including class D amplifier: |
| | This subclass is indented under subclass 250. Subject matter including an amplifier which utilizes switching-mode
techniques.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | and 10, for amplifiers which may use switching amplifiers
as a subcircuit thereof. |
| 207, | for amplifiers using switching-mode techniques. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 365+ for transistors used in a switching mode. |
|
| | |
| 252 | Including differential amplifier: |
| | This subclass is indented under subclass 250. Subject matter including an amplifier having two similar
input circuits so connected that they respond to the difference
between two voltages or currents, but effectively suppress like
voltages or currents.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 69, | for tube-type amplifiers functioning in a differential
mode. |
|
| | |
| 253 | Having field effect transistor: |
| | This subclass is indented under subclass 252. Subject matter wherein a field effect transistor (FET) is
utilized in the circuit with the differential amplifier.
| | (1)
Note. A field effect transistor (FET) is a semiconductor
device in which the resistance between two terminals, the source and
drain, depends on a field produced by a voltage applied to the third
terminal, the gate. |
| | (2)
Note. The field may modulate a depletion region, as in a
junction FET, or it may cause a conductivity change in a channel,
as in a MOS-FET. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 264, | for FET in combination with push-pull utilized in
complementary symmetry. |
| 269, | for FET in combination with push-pull amplifier. |
| 277, | for FET in other transistor amplifiers. |
| 300, | for FET in combined diverse-type circuit. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 581 for field-effect transistors used in miscellaneous
circuits. |
|
| | |
| 254 | Having gain control means: |
| | This subclass is indented under subclass 252. Subject matter including circuitry which controls the amplification
of the applied signal.
| | (1)
Note. Gain is any increase in power when a signal is transmitted
from one point to another. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 278+, | for other semiconductor amplifiers with gain control. |
SEE OR SEARCH CLASS:
| 348, | Television,
subclasses 645+ for color television circuits having gain control. |
|
| | |
| 255 | Having push-pull amplifier stage: |
| | This subclass is indented under subclass 252. Subject matter including an amplifier which has two identical
signal branches connected so as to operate in phase opposition and
with input and output connections, each balanced to ground.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 77, | for push-pull amplifiers with feedback neutralization. |
| 81+, | for push-pull amplifiers with feedback. |
| 118+, | for vacuum tube amplifiers including a push-pull
stage. |
| 262, | for push-pull amplifiers not in combination with
differential amplifiers. |
|
| | |
| 256 | Having temperature compensation means: |
| | This subclass is indented under subclass 252. Subject matter wherein temperature compensating means are
utilized to protect or stabilize the amplifying device from changes
in the ambient temperature.
| | (1)
Note. Changes in the ambient temperature can change the operating
characteristics of the amplifier and thereby change the output signal. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 266, | for temperature compensation in complementary push-pull
amplifiers. |
| 272, | for temperature compensation in a push-pull amplifier. |
| 289, | for temperature compensation in other transistor
amplifiers. |
|
| | |
| 257 | Having current mirror amplifier: |
| | This subclass is indented under subclass 252. Subject matter wherein an amplifier having a gain which
is substantially independent of the individual common emitter forward
current gains of its component transistor, is utilized.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 288, | for current mirror amplifier in other transistor
amplifiers. |
|
| | |
| 258 | Having common mode rejection circuit: |
| | This subclass is indented under subclass 252. Subject matter wherein means are utilized which ignore a
signal that appears simultaneously and in phase at both input terminals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 69, | for differential amplifiers which may include a
common mode rejection circuit. |
|
| | |
| 259 | Having D.C. feedback bias control for stabilization: |
| | This subclass is indented under subclass 252. Subject matter including a feedback circuit for direct currents
for the purpose of operating point stabilization.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching for input-output
comparison including those having feedback circuits for drift correction,
etc. |
| 270, | for D.C. feedback in push-pull complementary symmetry
amplifiers. |
| 290, | for D.C. feedback in other transistor amplifiers. |
|
| | |
| 260 | Having signal feedback means: |
| | This subclass is indented under subclass 252. Subject matter wherein a portion of the electrical signal
output energy is applied to the input of the amplifier.
| | (1)
Note. There is a shared impedance for the input and output
circuits involved. |
| | (2)
Note. The amplifier in this subclass may be any stage or
group of stages of a cascaded amplifier. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching input-output
comparison including those with feedback circuits. |
| 75+, | appropriate subclasses for vacuum tube signal feedback
amplifiers. |
| 265, | for signal feedback in complementary push-pull amplifiers. |
| 271, | for signal feedback in push-pull amplifier. |
| 282, | for signal feedback in gain control circuit. |
| 291, | for feedback in other transistor amplifiers. |
|
| | |
| 261 | Having particular biasing arrangement: |
| | This subclass is indented under subclass 252. Subject matter with specific details or distinctive characteristics
of the biasing means applied to the amplifying device.
| | (1)
Note. Merely claiming biasing means or bias filter by name
only, or broadly without significant detail or distinctive characteristics,
is insufficient for classification in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | for particular biasing in other amplifiers. |
| 267, | for particular biasing in combination with complementary
symmetry. |
| 273, | for particular biasing in combination with a push-pull
amplifier. |
| 285, | for particular biasing in gain control means. |
| 296, | for particular biasing in other transistor amplifiers. |
|
| | |
| 262 | Including push-pull amplifier: |
| | This subclass is indented under subclass 250. Subject matter including at least one push-pull amplifier.
| | (1)
Note. See the Glossary in this class for the definition of "Push-Pull
Amplifier". |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 77, | for push-pull amplifiers with feedback neutralization. |
| 81+, | for push-pull amplifiers with feedback. |
| 118+, | for vacuum tube amplifiers including a push-pull
stage. |
| 255, | for push-pull amplifiers in combination with differential
amplifiers. |
|
| | |
| 263 | Having complementary symmetry: |
| | This subclass is indented under subclass 262. Subject matter wherein semiconductor devices of opposite
conductivity are utilized.
| | (1)
Note. Complementary symmetry is an arrangement of NPN and
PNP transistors that provide push-pull operation from one input
signal. |
| | (2)
Note. There are two complementary types of conductivity in
semiconductors: The N-type where conduction is largely by electrons;
and the P-type where conduction appears to be largely carried by
positive charges (i.e., holes). In junction transistors which consist
of zones of more than one conductivity type of semiconductor material,
the conductivity is determined by the control zone so that the PNP-type
junction transistor is equivalent to an N-type semiconductor body
or an N-type point contact semiconductor device and an NPN junction
type similarly equivalent to a P-type of semiconductor device of
a single conductivity type of material. | |
| | |
| 264 | And field effect transistor: |
| | This subclass is indented under subclass 263. Subject matter wherein a field effect transistor (FET) is
utilized in the circuit.
| | (1)
Note. A field effect transistor (FET) is a semiconductor
device in which the resistance between two terminals, the source and
drain, depends on a field produced by a voltage applied to the third
terminal, the gate. |
| | (2)
Note. The field may modulate a depletion region, as in a
junction FET, or it may cause a conductivity change in a channel,
as in a MOS-FET. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 253, | for FET in combination with differential amplifiers. |
| 269, | for FET in combination with push-pull amplifiers. |
| 277, | for field effect transistors in other transistor
amplifiers. |
| 300, | for field effect transistors in combined diverse-type
semiconductor devices. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 581 for miscellaneous circuits using field-effect transistors. |
|
| | |
| 265 | And feedback means: |
| | This subclass is indented under subclass 263. Subject matter wherein a portion of the amplifier stage
output signal is returned to the input of the amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 260, | for signal feedback in differential amplifiers. |
| 271, | for signal feedback in push-pull amplifiers. |
| 282, | for signal feedback in gain control circuits. |
| 291, | for signal feedback in other transistor amplifiers. |
|
| | |
| 266 | And temperature compensation: |
| | This subclass is indented under subclass 263. Subject matter wherein temperature compensating means are
utilized to protect or stabilize the amplifying device from changes
in the ambient temperature.
| | (1)
Note. Changes in the ambient temperature can change the operating
characteristics of the amplifier and thereby change the output signal. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 256, | for temperature compensation in differential amplifiers. |
| 272, | for temperature compensation in a push-pull amplifier. |
| 289, | for temperature compensation in other transistor
amplifiers. |
|
| | |
| 267 | And particular biasing arrangement: |
| | This subclass is indented under subclass 263. Subject matter with specific details or distinctive characteristics
of the biasing means applied to the amplifying device.
| | (1)
Note. Merely claiming biasing means or bias filter by name
only, or broadly without significant detail or distinctive characteristics,
is insufficient for classification in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | for particular biasing in general. |
| 261, | for particular biasing in combination with a differential
amplifier. |
| 273, | for particular biasing in combination with a push-pull
amplifier. |
| 285, | for particular biasing in gain control circuits. |
| 296, | for particular biasing not in combination in any
of the aforementioned. |
|
| | |
| 268 | To eliminate crossover distortion: |
| | This subclass is indented under subclass 267. Subject matter wherein distortion which occurs at the points
of operation where the input signals cross over the zero reference
points is eliminated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 274, | for means to eliminate crossover distortion in noncomplementary,
symmetry push-pull amplifiers. |
|
| | |
| 269 | Having field effect transistors: |
| | This subclass is indented under subclass 262. Subject matter wherein a field effect transistor (FET) is
utilized in the circuit.
| | (1)
Note. A field effect transistor (FET) is a semiconductor
device in which the resistance between two terminals, the source and
drain, depends on a field produced by a voltage applied to the third
terminal, the gate. |
| | (2)
Note. The field may modulate a depletion region, as in a
junction FET, or it may cause a conductivity change in a channel,
as in a MOS-FET. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 253, | for FET in combination with a differential amplifier. |
| 264, | for FET in complementary symmetry in push-pull. |
| 277, | for FET in other transistor amplifiers. |
| 300, | for FET in combined diverse-type circuit. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 581 for miscellaneous circuits using field-effect transistors. |
|
| | |
| 270 | Having D.C. feedback bias control for stabilization: |
| | This subclass is indented under subclass 262. Subject matter with a feedback circuit for direct currents,
for the purpose of operating point stabilization.
| | (1)
Note. Included here are devices for compensating for changes
in temperature, aging, etc., of the semiconductor device, or devices
which may include means such as bypass capacitors to eliminate signal
feedback. |
| | (2)
Note. This does not include a mere bypassed emitter resistor
unless D.C. derived therefrom is applied to another electrode. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching for input-output
comparison including those having feedback circuits for drift correction,
etc. |
| 259, | for D.C. feedback in combination with a differential
amplifier. |
| 290, | for D.C. feedback in other transistor amplifiers. |
|
| | |
| 271 | Having signal feedback means: |
| | This subclass is indented under subclass 262. Subject matter wherein a portion of the electrical signal
output energy is applied to the input of the amplifier.
| | (1)
Note. There is a shared impedance for the input and output
circuits involved. |
| | (2)
Note. The amplifier of this subclass may be any stage or
group of stages of a cascaded amplifier. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching input-output
comparison including those with feedback circuits. |
| 75+, | appropriate subclasses for vacuum tube signal feedback
amplifiers. |
| 265, | for feedback in complementary push-pull amplifiers. |
| 282, | for signal feedback in gain control circuits. |
| 291, | for feedback in other transistor amplifiers. |
|
| | |
| 272 | Having temperature compensating means: |
| | This subclass is indented under subclass 262. Subject matter wherein temperature compensating circuits
or devices are utilized to protect or stabilize the semiconductor
amplifying devices from changes in the ambient temperature.
| | (1)
Note. Changes in the ambient temperature of a circuit"s
environment can change the operating characteristics of the semiconductor
amplifying device and thereby change the output signal. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 256, | for temperature compensation in a differential amplifier. |
| 266, | for temperature compensation in complementary push-pull
amplifiers. |
| 289, | for temperature compensation in other transistor
amplifiers. |
|
| | |
| 273 | Having particular biasing arrangement: |
| | This subclass is indented under subclass 262. Subject matter with specific details or distinctive characteristics
of the biasing means applied to the amplifying device.
| | (1)
Note. Merely claiming biasing means or bias filter by name
only, or broadly without significant details or distinctive characteristics,
is insufficient for classification in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | for particular biasing in general. |
| 261, | for particular biasing in combination with a differential
amplifier. |
| 267, | for particular biasing in combination with complementary
symmetry. |
| 285, | for particular biasing in gain control circuits. |
| 296, | for particular biasing in other transistor amplifiers. |
|
| | |
| 274 | To eliminate crossover distortion: |
| | This subclass is indented under subclass 273. Subject matter wherein distortion which occurs at the points
of operation where the input signals cross over the zero reference
points is eliminated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 268, | for means to eliminate crossover distortion in complementary
symmetry. |
|
| | |
| 275 | Having balanced to unbalanced circuitry and vice versa: |
| | This subclass is indented under subclass 262. Subject matter wherein one of the signal input means or
signal output means is coupled to or from the semiconductor amplifier
by a balanced circuit, the other signal coupling means coupled to
or from the semiconductor amplifier balanced circuit.
| | (1)
Note. For the definition of a "Balanced Circuit",
see the class definition, Glossary. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 301, | for balanced to unbalanced circuits and vice versa
in other transistor amplifiers. |
|
| | |
| 276 | Having transformer: |
| | This subclass is indented under subclass 262. Subject matter wherein a transformer is included in the
circuit.
| | (1)
Note. The transformer can be in the input, output, interstage,
or any combination of the aforementioned. | |
| | |
| 277 | Including field effect transistor: |
| | This subclass is indented under subclass 250. Subject matter wherein a field effect transistor (FET) is
utilized in the amplifier circuit.
| | (1)
Note. A field effect transistor (FET) is a semiconductor
device in which the resistance between two terminals, the source and
drain, depends on a field produced by a voltage applied to the third
terminal, the gate. |
| | (2)
Note. The field may modulate a depletion region, as in a
junction FET, or it may cause a conductivity change in a channel,
as in a MOS-FET. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 253, | for FET in differential amplifiers. |
| 264, | for FET in combination with push-pull utilized in
complementary symmetry. |
| 269, | for FET in combination with push-pull amplifiers. |
| 300, | for FET in combined verse-type circuit. |
|
| | |
| 278 | Including gain control means: |
| | This subclass is indented under subclass 250. Subject matter including circuitry which controls the amplification
of the applied signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 52, | for amplifiers having pilot frequency control means. |
| 96, | for feedback amplifiers combined with control of
bias voltage of a signal amplifier. |
| 123, | for push-pull amplifiers having significant power
or bias supply circuits including those with bias control means. |
| 127+, | for amplifiers with control of power supply or bias
voltage. |
| 143, | for amplifiers having a thermally responsive impedance. |
| 144+, | for amplifiers having a variable impedance in the
signal path varied by a separate control path. |
| 155+, | for amplifiers having unicontrol of coupling or
associated circuits including unicontrol of signal input or output
potentiometers, etc.. |
| 157+, | 185+ and 192+, for interstage
input or output coupling, respectively, including variable impedance
means in such coupling. |
| 254, | for gain control means in combination with a differential
amplifier. |
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks, particularly
subclasses 14 , 16, and 17.1 for combined amplifier compressor
and expander means, pilot controlled means, and automatically controlled
systems, respectively; subclasses 24+ for coupling networks which
may include signal amplitude control means; subclasses 213+ for negative
resistance and/or reactance networks of the active element
type; and subclass 81 for attenuators. |
| 455, | Telecommunications,
subclasses 232.1+ for volume control, especially subclasses 234.1+ for
automatic volume control. |
|
| | |
| 279 | And significant control voltage developing means: |
| | This subclass is indented under subclass 278. Subject matter including specific details or distinctive
characteristics of the gain control developing means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 127+, | 143 and 144+, for other amplifiers having
gain control systems which may have significant control voltage developing
means. |
SEE OR SEARCH CLASS:
| 455, | Telecommunications,
subclasses 232.1+ for receivers which may have significant control
voltage developing means as part of a gain control system. |
|
| | |
| 280 | With delay means: |
| | This subclass is indented under subclass 279. Subject matter including circuit means which impart to the
control voltage, a minimum level at which the control voltage developing
means begins to function.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 127+, | 143 and 144+, for gain-controlled amplifiers
which may have delay means. |
SEE OR SEARCH CLASS:
| 455, | Telecommunications,
subclasses 242.1+ for gain-controlled receivers which may have delay
means. |
|
| | |
| 281 | With time constant means: |
| | This subclass is indented under subclass 279. Subject matter including a circuit for filtering the control
voltage, and wherein specific details or distinctive characteristics
of such circuit are claimed.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 127+, | 143 and 144+, for amplifiers which may
include time-constant means in the control voltage path thereof. |
SEE OR SEARCH CLASS:
| 455, | Telecommunications,
subclasses 239.1+ for gain-controlled receivers which may include
time-constant means in the control voltage path thereof. |
|
| | |
| 282 | Having feedback means acting as variable impedance: |
| | This subclass is indented under subclass 278. Subject matter including a feedback means acting as a variable
impedance to control the gain of the amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 86, | for amplifiers having variable impedance in feedback
path varied by separate control path. |
|
| | |
| 283 | Having emitter degeneration: |
| | This subclass is indented under subclass 282. Subject matter including a feedback means acting as a variable
impedance in the common electrode of the amplifier to control the
gain of the amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 95, | for amplifiers having nonlinear impedance means
in the cathode impedance feedback path. |
|
| | |
| 284 | Having attenuation means in signal transmission path: |
| | This subclass is indented under subclass 278. Subject matter having attenuation means in signal transmission
path that controls the gain of the amplifier.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 52, | for amplifiers having pilot frequency control means. |
| 143, | for amplifiers having thermally responsive means. |
| 144+, | for amplifiers having variable impedance for signal
channel controlled by separate control path. |
SEE OR SEARCH CLASS:
| 455, | Telecommunications,
subclass 249.1 for gain-controlled receiver having variable impedance
in the control circuit. |
|
| | |
| 285 | Having particular biasing means: |
| | This subclass is indented under subclass 278. Subject matter having specific details or distinctive characteristics
of a biasing means for applying a biasing voltage to the amplifying device.
| | (1)
Note. Merely claiming biasing means or bias filter by name
only, or broadly without significant detail or distinctive characteristics,
is insufficient for classification in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 127+, | for amplifiers with control of power supply or bias
voltage. |
| 199+, | for particular biasing in other amplifiers. |
| 261, | for particular biasing in differential amplifiers. |
| 267, | for particular biasing in combination with complementary
symmetry. |
| 273, | for particular biasing in combination with a push-pull
amplifier. |
| 285, | for particular biasing in gain control circuits. |
| 296, | for particular biasing in other transistor amplifiers. |
|
| | |
| 286 | Including distributed parameter-type coupling: |
| | This subclass is indented under subclass 250. Subject matter including coupling means which has both distributive
capacitance and distributive inductance at high frequencies.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 53+, | for amplifiers having distributed-type coupling. |
SEE OR SEARCH CLASS:
| 331, | Oscillators,
subclasses 56+ for oscillators having distributed parameter resonator. |
| 333, | Wave Transmission Lines and Networks,
subclasses 219+ for distributed parameter resonator, and subclasses
236+ for long lines having distributed parameters. |
|
| | |
| 287 | Of diode type: |
| | This subclass is indented under subclass 286. Subject matter including amplifying means of the diode type.
SEE OR SEARCH CLASS:
| 331, | Oscillators,
subclass 107 for diode-type oscillators. |
|
| | |
| 288 | Including current mirror amplifier: |
| | This subclass is indented under subclass 250. Subject matter wherein an amplifier having a gain which
is substantially independent of the individual common emitter forward
current gains of its component transistor is utilized.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 257, | for current mirror amplifiers in combination with
differential amplifiers. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 530+ for miscellaneous transistor circuits used for
power supply or bias regulation. |
|
| | |
| 289 | Including temperature compensation means: |
| | This subclass is indented under subclass 250. Subject matter wherein temperature compensating means are
utilized to protect or stabilize the amplifying device from changes
in the ambient temperature.
| | (1)
Note. Changes in the ambient temperature can change the operating
characteristics of the amplifier and thereby change the output signal. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 256, | for temperature compensation in a differential amplifier. |
| 266, | for temperature compensation in complementary push-pull
amplifiers. |
| 272, | for temperature compensation in a push-pull amplifier. |
|
| | |
| 290 | Including D.C. feedback bias control for stabilization: |
| | This subclass is indented under subclass 250. Subject matter with feedback circuit for direct currents,
for the purpose of operating point stabilization as compensating
for changes in temperature, aging, etc., of the semiconductor device,
or devices, which may include means such as bypass capacitors to
eliminate signal feedback.
| | (1)
Note. This does not include a mere bypass emitter resistor
unless D.C. derived therefrom is applied to another electrode. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching for input-output
comparison including those having feedback circuits for drift correction,
etc. |
| 97, | for amplifiers including D.C. path for signal feedback. |
| 259, | for D.C. feedback in differential amplifiers. |
| 270, | for D.C. feedback in push-pull complementary symmetry
amplifiers. |
|
| | |
| 291 | Including signal feedback means: |
| | This subclass is indented under subclass 250. Subject matter wherein a portion of the electrical signal
output energy is applied to the input of the amplifier.
| | (1)
Note. There is a shared impedance for the input and output
circuits involved. |
| | (2)
Note. The amplifier of this subclass may be any stage or
group of stages of a cascaded amplifier. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 9, | for amplifiers with periodic switching input-output
comparison including those with feedback circuits. |
| 75+, | appropriate subclasses for vacuum tube signal feedback
amplifiers. |
| 260, | for signal feedback in differential amplifiers. |
| 265, | for feedback in complementary push-pull amplifiers. |
| 271, | for signal feedback in push-pull amplifiers. |
| 282, | for signal feedback in gain control circuits. |
|
| | |
| 292 | Having compensation for interelectrode impedance: |
| | This subclass is indented under subclass 291. Subject matter wherein signal feedback means are provided
for, compensating for, or nullifying the undesirable feedback caused
by any of the internal interelectrode impedances of the semiconductor
amplifying device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 76+, | for neutralization through compensation by signal
feedback of the effects of interelectrode impedance in vacuum tube
amplifiers. |
|
| | |
| 293 | Having negative feedback: |
| | This subclass is indented under subclass 291. Subject matter wherein the signal feedback which is superimposed
on the input signal has at least one component thereof opposite
in phase to the input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 75+, | for signal feedback in other amplifiers. |
|
| | |
| 294 | Having frequency responsive means or phase shift means
in the feedback path: |
| | This subclass is indented under subclass 291. Subject matter having frequency-responsive means or phase-shift
means in the feedback path that causes corresponding changes in amplifier
gain.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 107, | and 109, for amplifiers having frequency- or phase-responsive
means in the feed-back path. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 113+ for miscellaneous frequency control, subclasses
231+ for a phase shift of less than an input signal period,
subclasses 2+ for phase discriminating without subsequent control,
and subclasses 39+ for frequency discriminating without
subsequent control. |
|
| | |
| 295 | Including plural amplifier channels: |
| | This subclass is indented under subclass 250. Subject matter having more than one signal transmission
path, each of which contains an amplifier (e.g., plural inputs or
plural outputs).
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 84, | for signal feedback amplifiers having plural channels. |
| 124+, | for amplifiers having plural amplifier channels. |
| 147, | for amplifiers having plural separate inputs. |
| 148, | for amplifiers having plural separate outputs. |
|
| | |
| 296 | Including particular biasing arrangement: |
| | This subclass is indented under subclass 250. Subject matter with specific details or distinctive characteristics
of the biasing means applied to the amplifying device.
| | (1)
Note. Merely claiming biasing means or bias filter by name
only, or broadly without significant detail or distinctive characteristics,
is sufficient for classification in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | for particular biasing in other amplifiers. |
| 261, | for particular biasing in differential amplifiers. |
| 267, | for particular biasing in combination with complementary
symmetry. |
| 273, | for particular biasing in combination with push-pull
amplifier. |
| 285, | for particular biasing in signal amplitude control. |
|
| | |
| 297 | Including particular power supply circuitry: |
| | This subclass is indented under subclass 250. Subject matter including specific details or distinctive
characteristics of the source of electrical energy applied to the
semiconductor amplifying device.
| | (1)
Note. This includes means to apply such energy source, the
circuits through which such source is applied, and means for isolating
such source from the signal path or other amplifier circuits. |
| | (2)
Note. Merely claiming power supply source by name only, or
broadly without significant detail or distinctive characteristics,
is insufficient for classification in this subclass. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 199+, | for amplifiers generally involving bias or power
supply. See the search notes under subclass 199. |
|
| | |
| 298 | Including protection means: |
| | This subclass is indented under subclass 250. Subject matter including circuits or devices for protecting
the amplifying means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 207+, | for amplifiers having protection circuitry. |
|
| | |
| 299 | Including combined diverse-type semiconductor device: |
| | This subclass is indented under subclass 250. Subject matter including plural semiconductor devices and
at least one semiconductor device which is different in its physical
characteristics or in materials, and which also amplifies the signal.
| | (1)
Note. Materials which may be a diode of the nonamplifying
type, or which may be an additional signal carrier semiconductor
amplifying device including an amplifier not previously provided
for in this schedule. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 94, | and 110, for vacuum tube feedback amplifiers having
nonlinear impedance elements. |
| 138, | and 140, for amplifiers having a rectifier, which
may be a semiconductor diode, in a bias control circuit for the input
or gain control electrode. |
| 143, | for vacuum tube amplifiers having a thermally responsive
impedance. |
| 144+, | for vacuum tube amplifiers having a separately controlled
variable impedance in the signal path, which may be a semiconductor. |
| 164, | for vacuum tube amplifiers with a diode in the interstage
coupling which may be a semiconductor. |
| 174, | for a piezoelectric crystal or electromechanical
transducer broadly in the interstage coupling of a vacuum tube amplifier. |
| 183, | for vacuum tube amplifiers having D.C. interstage
coupling with a nonlinear device therein. |
|
| | |
| 300 | Bipolar or unipolar (FET): |
| | This subclass is indented under subclass 299. Subject matter wherein the additional semiconductor device
may be a bipolar or unipolar transistor.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 253, | for field effect transistor (FET) in combination
with a differential amplifier. |
| 264, | for FET in combination with complementary symmetry
push-pull amplifiers. |
| 269, | for FET in combination with other push-pull amplifiers. |
| 277, | for other field effect transistors. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclass 581 for miscellaneous FET circuits. |
|
| | |
| 301 | Including balanced to unbalanced circuits and vice versa: |
| | This subclass is indented under subclass 250. Subject matter wherein one of the signal input means or
signal output means is coupled to or from the semiconductor amplifier
by a balanced circuit, the other signal coupling means coupled to
or from the semiconductor amplifier unbalanced circuit.
| | (1)
Note. For the definition of a "Balanced Circuit",
see the Glossary in this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 275, | for balanced to unbalanced circuits in push-pull
amplifiers. |
|
| | |
| 302 | Including frequency-responsive means in the signal transmission
path: |
| | This subclass is indented under subclass 250. Subject matter including frequency-responsive means in the
signal transmission path that causes corresponding changes in the
amplifier gain.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 157+, | 185+ and 192+, for interstage
input or output coupling, respectively, including variable impedance
means in such coupling. |
| 294, | having frequency-responsive means or phase-shift
means in the feedback path. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 113+ for miscellaneous frequency control, subclasses
231+ for a phase shift of less than an input signal period,
subclasses 2+ for phase discriminating without subsequent control,
and subclasses 39+ for frequency discriminating without
subsequent control. |
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for frequency or phase sensitive circuits in wave transmission
lines and networks. |
|
| | |
| 303 | Including an active device in the filter means: |
| | This subclass is indented under subclass 302. Subject matter including a transistor or active diode in
the filter network.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 107, | 109 and 294, for circuits having frequency-responsive
means or phase-shift means in the feedback path. |
SEE OR SEARCH CLASS:
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 552+ for miscellaneous circuits suppressing an unwanted
signal using an active filter. |
| 333, | Wave Transmission Lines and Networks,
subclasses 24+ for frequency or phase sensitive circuits in wave transmission
lines and networks. |
|
| | |
| 304 | And equalizing means: |
| | This subclass is indented under subclass 302. Subject matter including a network connected to a line to
correct or control its transmission frequency characteristics.
SEE OR SEARCH CLASS:
| 333, | Wave Transmission Lines and Networks,
subclass 28 for equalizers used in wave transmission lines
and networks. |
|
| | |
| 305 | And tuning means: |
| | This subclass is indented under subclass 302. Subject matter including a manually adjustable frequency
selecting means.
SEE OR SEARCH CLASS:
| 334, | Tuners, appropriate subclasses for tuning circuits. |
| 455, | Telecommunications,
subclasses 120+ for transmitters having tuning means; and subclasses
150.1+ for receivers having tuning means. |
|
| | |
| 307 | Integrated circuits: |
| | This subclass is indented under subclass 250. Subclass matter under having a combination of interconnected
elements inseparably associated on or within a continuous substrate.
| | (1)
Note. If a claimed preferred embodiment of a patent application
includes details of means to apply a variable electrical signal
to an IC amplifying device, or details of means to utilize the output of
an IC amplifying device, that application is properly classified
in this subclass. |
| | (2)
Note. If, however, a claimed preferred embodiment of a patent
application is limited to details of an IC amplifying device, without
details of the input or output (utilization) means, or the input
or output (utilization) means are recited in name only, then the
application is properly classified outside this class. |
SEE OR SEARCH CLASS:
| 257, | Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for active solid-state devices,
especially
subclasses 115 , 123, and 162-166 which are directed to devices
involving amplification. See the (2) Note above. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 564+ for miscellaneous circuits which are integrated. |
|
| | |
| 308 | Including atomic particle or radiant energy impinging on
a semiconductor: |
| | This subclass is indented under subclass 250. Subject matter in which the amplifying device semiconductor
body is subjected to radiant energy which may be in the form of
light, free (unrestrained) electromagnetic energy, gamma rays, etc..,
or atomic particle bombardment, such as alpha or beta rays, etc..
| | (1)
Note. If a claimed preferred embodiment of a patent application
includes details of means to apply a variable electrical signal
to an IC amplifying device, or details of means to utilize the output of
an IC amplifying device, that application is properly classified
elsewhere in this class (330). |
| | (2)
Note. If, however, a claimed preferred embodiment of a patent
application is limited to details of an IC amplifying device without
details of the input or output (utilization) means, or the input
or output (utilization) means are recited in name only, then the
application is properly classified elsewhere outside this class. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 4, | for maser-type amplifying device which may involve
a semiconductor. |
| 5, | for solid element wave propagating amplifying devices
involving coupling or activation by electromagnetic wave energy
applied through wave energy constraining wave propagating means,
such as by wave guide. |
| 307, | for a claimed preferred embodiment of a patent application
includes details of means to apply a variable electrical signal
to an IC amplifying device, or details of means to utilize the output of
an IC amplifying device. |
SEE OR SEARCH CLASS:
| 250, | Radiant Energy, particularly
subclasses 370.01+ for methods and apparatus using an invisible radiant energy-responsive
semiconductor device. |
| 257, | Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for active solid-state devices,
especially
subclass 115 which is directed to light responsive devices involving
amplification. See (2) Note above. |
| 313, | Electric Lamp and Discharge Devices, appropriate subclasses for discharge devices involving
the structure of ray energy generating, beaming and focusing, in
the form of electron beams, alpha ray, and X-ray emanations. |
| 315, | Electric Lamp and Discharge Devices: Systems,
subclasses 1+ for cathode ray discharge devices involving circuits
or special circuit structure associated with the device. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems,
subclasses 509+ for miscellaneous nonlinear solid-state circuits
subjected to some external effect. |
| 359, | Optical: Systems and Elements,
subclasses 333+ for laser amplifiers. |
|
| | |
| 309 | Involving structure of three diverse function electrode
type: |
| | This subclass is indented under subclass 250. Subject matter wherein the semiconductor device is provided
in three diverse-type electrodes for coupling the signal energy
input and output, additional biasing or gain control, etc.., and
the application of the controlled electrical energy source in which
each electrode performs a distinct function.
| | (1)
Note. If a claimed preferred embodiment of a patent application
includes details of means to apply a variable electrical signal
to an IC amplifying device, or details of means to utilize the output of
an IC amplifying device, that application is properly classified
elsewhere in this class. |
| | (2)
Note. If, however, a claimed preferred embodiment of a patent
application is limited to details of an IC amplifying device without
details of the input or output (utilization) means, or the input
or output (utilization) means are recited in name only, then the
application is properly classified elsewhere outside this class. |
SEE OR SEARCH CLASS:
| 257, | Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for active solid-state devices,
especially
subclasses 115 , 123 and 162 through 166 which are directed to
devices involving amplification. |
| 327, | Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, appropriate subclasses for similar semiconductor
devices in miscellaneous circuits. |
|
| | |
| 310 | Including plural stages cascaded: |
| | This subclass is indented under subclass 250. Subject matter including a plurality of stages of amplification,
such that the input signal for each stage, except the first, is
the output of the preceding stage.
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 3, | for plural diverse-type amplifying devices which
may be cascaded and which may include a semiconductor-type amplifying
device. |
| 70+, | for series energized vacuum tube amplifiers which
may be cascaded. |
| 88+, | 92 and 98+, for cascaded amplifiers with
signal feedback. |
| 150, | for cascaded vacuum tube amplifying devices of different
characteristics. |
| 151, | for cascaded vacuum tube amplifier devices with
means to bypass a stage. |
| 152+, | for cascaded vacuum tube amplifier means differently
coupled between stages. |
| 157+, | for interstage coupling between stages of amplifying
devices. |
|
| | |
| 311 | Having different configurations: |
| | This subclass is indented under subclass 310. Subject matter wherein at least one of the cascaded stages
is of a different configuration from at least one of the other cascaded
stages.
| | (1)
Note. In a semiconductor amplifier having emitter, base,
and collector electrodes, input signal current flows through two
electrodes thereof, and output signal current flows through two electrodes
thereof, one of the electrodes being common to both input and output circuits.
Therefore, in the three electrode semiconductor amplifier, there
is a common electrode, an input electrode and an output electrode.
By the configuration of a semi-conductor amplifier is meant the
arrangement of base, emitter, and collector electrodes thereof,
as the input, common, and output electrodes thereof. The configuration
is usually referred to as common base, common emitter, or common
collector configuration, but this does not completely define the
configuration which must have at least one of the other semiconductor electrodes
identified by its function as input or output electrode. |
SEE OR SEARCH THIS CLASS, SUBCLASS:
| 153, | for cascaded vacuum tube amplifier devices with
differently coupled interstage circuits including at least one cathode
follower stage. |
| 157+, | appropriate subclasses thereunder, for interstage
coupling to or from electrodes and as cathode, or from electrodes
such as cathode or screen grid not used in the majority of vacuum tube
amplifiers as input or output electrode. |
| 168, | for vacuum tube interstage transformer coupling
from the cathode. |
|
| | |
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CLASS 330,