Class 330: AMPLIFIERS ( Manual of U.S. Patent Classification )

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Manual of U.S. Patent Classification
as of June 30, 2000


Class
330
AMPLIFIERS


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Subclass Title
ClassTitle ===> AMPLIFIERS
1R[Patents]WITH DIVERSE-TYPE ART DEVICE
1A[Patents] . With process control system
2[Patents]WITH AMPLIFIER CONDITION INDICATING OR TESTING MEANS
3[Patents]WITH PLURAL DIVERSE-TYPE AMPLIFYING DEVICES
4[Patents]WITH MASER-TYPE AMPLIFYING DEVICE
4.5[Patents]PARAMETRIC AMPLIFIERS
4.6[Patents] . Traveling wave type
4.7[Patents] . . Electron beam device
4.8[Patents] . Gyromagnetic type (e.g., ferrite)
4.9[Patents] . Semiconductor type (e.g., with semiconductor diode)
5[Patents]WITH SOLID ELEMENT WAVE PROPAGATING AMPLIFYING DEVICE
5.5[Patents] . Phonon type (e.g., ultrasonic wave propagating device)
6[Patents]WITH HALL EFFECT TYPE MEANS
7[Patents]WITH CAPACITIVE AMPLIFYING DEVICE
8[Patents]WITH SATURABLE REACTOR-TYPE AMPLIFYING DEVICE
9[Patents]WITH PERIODIC SWITCHING INPUT-OUTPUT (E.G., FOR DRIFT CORRECTION)
10[Patents]MODULATOR-DEMODULATOR-TYPE AMPLIFIER
11[Patents]WITH D.C. REINSERTION CIRCUIT
250[Patents]WITH SEMICONDUCTOR AMPLIFYING DEVICE (E.G., TRANSISTOR)
251[Patents] . Including Class D amplifier
252[Patents] . Including differential amplifier
253[Patents] . . Having field effect transistor
254[Patents] . . Having gain control means
255[Patents] . . Having push-pull amplifier stage
256[Patents] . . Having temperature compensation means
257[Patents] . . Having current mirror amplifier
258[Patents] . . Having common mode rejection circuit
259[Patents] . . Having D.C. feedback bias control for stabilization
260[Patents] . . Having signal feedback means
261[Patents] . . Having particular biasing arrangement
262[Patents] . Including push-pull amplifier
263[Patents] . . Having complementary symmetry
264[Patents] . . . And field effect transistor
265[Patents] . . . And feedback means
266[Patents] . . . And temperature compensation
267[Patents] . . . And particular biasing arrangement
268[Patents] . . . . To eliminate crossover distortion
269[Patents] . . Having field effect transistor
270[Patents] . . Having D.C. feedback bias control for stabilization
271[Patents] . . Having signal feedback means
272[Patents] . . Having temperature compensating means
273[Patents] . . Having particular biasing arrangement
274[Patents] . . . To eliminate crossover distortion
275[Patents] . . Having balanced to unbalanced circuitry and vice versa
276[Patents] . . Having transformer
277[Patents] . Including field effect transistor
278[Patents] . Including gain control means
279[Patents] . . And significant control voltage developing means
280[Patents] . . . With delay means
281[Patents] . . . With time constant means
282[Patents] . . Having feedback means acting as variable impedance
283[Patents] . . . Having emitter degeneration
284[Patents] . . Having attenuation means in signal transmission path
285[Patents] . . Having particular biasing means
286[Patents] . Including distributed parameter-type coupling
287[Patents] . . Of diode type
288[Patents] . Including current mirror amplifier
289[Patents] . Including temperature compensation means
290[Patents] . Including D.C. feedback bias control for stabilization
291[Patents] . Including signal feedback means
292[Patents] . . Having compensation for interelectrode impedance
293[Patents] . . Having negative feedback
294[Patents] . . Having frequency-responsive means or phase-shift means in feedback path
295[Patents] . Including plural amplifier channels
296[Patents] . Including particular biasing arrangement
297[Patents] . Including particular power supply circuitry
298[Patents] . Including protection means
299[Patents] . Including combined diverse-type semiconductor device
300[Patents] . . Bipolar or unipolar (FET)
301[Patents] . Including balanced to unbalanced circuits and vice versa
302[Patents] . Including frequency-responsive means in the signal transmission path
303[Patents] . . Including an active device in the filter means
304[Patents] . . And equalizing means
305[Patents] . . And tuning means
306[Patents] . . And bandpass, broadband (e.g., wideband) or sidepass means
307[Patents] . Integrated circuits
308[Patents] . Including atomic particle or radiant energy impinging on a semiconductor
309[Patents] . Involving structure of three diverse function electrode type
310[Patents] . Including plural stages cascaded
311[Patents] . . Having different configurations
41[Patents]WITH GAS OR VAPOR TUBE AMPLIFYING DEVICE
42[Patents]WITH SECONDARY ELECTRON EMISSION TUBE AMPLIFYING DEVICE
43[Patents]WITH TRAVELING WAVE-TYPE TUBE
44[Patents]WITH ELECTRON BEAM TUBE AMPLIFYING DEVICE
45[Patents] . Having electrode coupled to cavity resonator
46[Patents] . Having deflecting means
47[Patents]WITH MAGNETICALLY INFLUENCED DISCHARGE DEVICE (E.G., MAGNETRONS)
48[Patents] . Having signal applied to magnetic means
49[Patents]WITH VACUUM TUBE HAVING DISTRIBUTED PARAMETER IMPEDANCE CHARACTERISTICS
50[Patents]WITH DUMMY TUBE
51[Patents]COMBINED WITH AUTOMATIC AMPLIFIER DISABLING SWITCH MEANS
52[Patents]WITH PILOT FREQUENCY CONTROL MEANS
53[Patents]WITH DISTRIBUTED PARAMETER-TYPE COUPLING MEANS
54[Patents] . Distributed amplifier
55[Patents] . Push-pull
56[Patents] . Waveguide, cavity, or concentric line resonator
57[Patents] . Artificial line
58[Patents]WITH ROTATING DYNAMOELECTRIC AMPLIFYING DEVICE
59[Patents]HAVING LIGHT-CONTROLLED OR ACTIVATED DEVICE (I.E., NOT LIGHT SIGNAL)
60[Patents]HAVING MAGNETOSTRICTIVE-TYPE AMPLIFYING DEVICE
61R[Patents]WITH RESISTIVE-TYPE AMPLIFYING DEVICE
62[Patents] . Magnetoresistive type
61A[Patents] . Negative resistance amplifiers
63[Patents]WITH MAGNETIC MEANS AMPLIFYING DEVICE
64[Patents]WITH SPACE CHARGE GRID TUBE
65[Patents]INVOLVING STRUCTURE OTHER THAN THAT OF TRANSFORMERS PER SE
66[Patents] . With printed circuits
67[Patents] . With capacitive structure
68[Patents] . With shielding means
69[Patents]SUM AND DIFFERENCE AMPLIFIERS
70[Patents]ANODE ENERGIZED THROUGH DISCHARGE PATH OF CONTROLLED VACUUM TUBE
71[Patents] . Plural discharge paths traversed by anode supply
72[Patents] . . Amplifier devices in arms of a bridge
73[Patents] . Plural outputs
74[Patents] . Separate signal inputs to series devices
75[Patents]SIGNAL FEEDBACK
76[Patents] . Compensating for inter-electrode impedance (e.g., neutralization)
77[Patents] . . At least one push-pull stage
78[Patents] . . To or from electrode common to input and output
79[Patents] . . By transformer feedback
80[Patents] . . By coil in parallel to and resonating with inter-electrode capacity
81[Patents] . At least one push-pull signal stage
82[Patents] . . Positive and negative feedback
83[Patents] . . Including D.C. path for signal feedback
84[Patents] . Plural amplifier channels
85[Patents] . Amplifier in signal feedback path
86[Patents] . Variable impedance in feedback path varied by separate control path
87[Patents] . Cathode impedance feedback
88[Patents] . . Cascade amplifier stages with cathode-cathode feedback
89[Patents] . . . Between adjacent stages
90[Patents] . . Combined with diverse-type feedback coupling
91[Patents] . . . Diverse feedback to or from cathode
92[Patents] . . . . Feedback to cathode impedance of a prior stage
93[Patents] . . . Including positive feedback
94[Patents] . . Frequency responsive means in cathode impedance feedback path
95[Patents] . . Nonlinear impedance means in cathode impedance feedback path
96[Patents] . Combined with control of bias voltage of signal amplifier
97[Patents] . Including D.C. path for signal feedback
98[Patents] . In cascade amplifiers
99[Patents] . . Multiple feedback
100[Patents] . . . A feedback to input of a prior stage
101[Patents] . Positive and negative feedback in same path at different frequencies
102[Patents] . Current and voltage feedback
103[Patents] . Multiple feedback paths
104[Patents] . . Positive and negative feedback
105[Patents] . From impedance in series with output load (e.g., current feedback)
106[Patents] . In series with input source
107[Patents] . Phase shift means in loop path
108[Patents] . Potentiometer common to signal and feedback path
109[Patents] . Frequency responsive feedback means
110[Patents] . Nonlinear impedance element in loop path
111[Patents] . To or from an auxiliary grid or to the anode
112[Patents] . Positive feedback
113[Patents]POLYPHASE POWER SUPPLY (I.E., FOR AN ELECTRODE, CATHODE HEATER, OR FILAMENT)
114[Patents]UNRECTIFIED A.C. POWER SUPPLY FOR AN ELECTRODE (I.E., NOT THE HEATER)
115[Patents] . Applied to filamentary cathode
116[Patents]WITH BALANCED-TO-UNBALANCED COUPLING
117[Patents]WITH UNBALANCED-TO-BALANCED COUPLING
118[Patents]INCLUDING A PUSH-PULL STAGE
119[Patents] . Coupling to or from cathode in push-pull
120[Patents] . Interstage coupling between push-pull
121[Patents] . . D.C. coupling
122[Patents] . Input and/or output coupling for push-pull
123[Patents] . Power or bias supply circuits and control thereof
124R[Patents]WITH PLURAL AMPLIFIER CHANNELS (E.G., PARALLEL AMPLIFIER CHANNELS)
125[Patents] . D.C. and A.C. amplifier channels
126[Patents] . Amplifying different frequencies in different channels
124D[Patents] . Redundant amplifier circuits
127[Patents]WITH CONTROL OF POWER SUPPLY OR BIAS VOLTAGE
128[Patents] . Control means for anode of screen grid circuit
129[Patents] . With control of input electrode or gain control electrode bias
130[Patents] . . Bias controlled by separate external control source
131[Patents] . . Control of bias on separate gain control electrode
132[Patents] . . Frequency selective means to select control signal from amplifier channel
133[Patents] . . Different bias control means for different stages of cascade amplifier
134[Patents] . . Plural different bias control voltages provided by separate means
135[Patents] . . Amplitude limiting or bias voltage
136[Patents] . . Bias control signal from input of amplifier
137[Patents] . . Oscillator supplies or controls bias
138[Patents] . . Bias controlled by biased rectifier or discharge device
139[Patents] . . Electronic tube controls bias
140[Patents] . . Rectifier in bias control circuit
141[Patents] . . Time constant circuit in bias control circuit
142[Patents] . . Cathode resistor supplies bias (e.g., self-biasing circuits)
143[Patents]THERMALLY RESPONSIVE IMPEDANCE
144[Patents]VARIABLE IMPEDANCE FOR SIGNAL CHANNEL CONTROLLED BY SEPARATE CONTROL PATH
145[Patents] . Electron tube or diode as impedance
146[Patents]WHEATSTONE BRIDGE WITH AMPLIFIER IN AT LEAST ONE ARM
147[Patents]PLURAL SIGNAL INPUTS
148[Patents]PLURAL SIGNAL OUTPUTS
149[Patents]HUM OR NOISE OR DISTORTION BUCKING INTRODUCED INTO SIGNAL CHANNEL
150[Patents]CASCADED SIMILAR AMPLIFYING DEVICE OF DIFFERENT CHARACTERISTICS
151[Patents]WITH AMPLIFIER BYPASS MEANS (E.G., FORWARD FEED)
152[Patents]CASCADED DIFFERENTLY COUPLED BETWEEN STAGES
153[Patents] . Including a cathode follower stage
154[Patents] . Transformer or resonant circuit in interstage coupling (e.g., stagger tuning)
155[Patents]UNICONTROL OF COUPLING OR THE CIRCUITS ASSOCIATED THEREWITH
156[Patents]BOOTSTRAP COUPLING
157[Patents]INTERSTAGE COUPLING
158[Patents] . Coupling to cathode
159[Patents] . . D.C. coupling
160[Patents] . Coupling to plate or auxiliary grid
161[Patents] . . D.C. coupling
162[Patents] . Output coupling from grid
163[Patents] . . D.C. coupling
164[Patents] . With electronic tube or diode in coupling circuit
165[Patents] . Transformer coupling
166[Patents] . . With additional reactive coupling
167[Patents] . . With additional impedance connected to "P" or "S" circuits
168[Patents] . . From cathode
169[Patents] . . With means for adjusting inductive coupling
170[Patents] . . With shielding
171[Patents] . . With transformer structure
172[Patents] . Coupling from cathode
173[Patents] . . D.C. coupling
174[Patents] . With electromechanical transducer (e.g., piezoelectric crystal)
175[Patents] . With lattice or Wheatstone bridge network in coupling circuits
176[Patents] . With T, H, or Pi network in coupling circuit
177[Patents] . With coupling or blocking capacitor
178[Patents] . . With R or L in series between stages
179[Patents] . . L in anode or grid circuit
180[Patents] . . With R in anode and grid circuit (RC coupling)
181[Patents] . D.C. coupled
182[Patents] . . With series reactive element between stages
183[Patents] . . With nonlinear device
184[Patents] . . With series resistance between stages
185[Patents]INPUT NETWORKS
186[Patents] . To cathode
187[Patents] . . D.C. coupled
188[Patents] . Transformer coupled
189[Patents] . . With additional impedance connected to "P" or "S" circuits
190[Patents] . . With transformer structure
191[Patents] . D.C. coupled
192[Patents]OUTPUT NETWORKS
193[Patents] . From cathode
194[Patents] . . D.C. coupled
195[Patents] . Transformer coupled
196[Patents] . . With additional impedance connected to "P" or "S" circuit
197[Patents] . . With transformer structure
198[Patents] . D.C. coupled
199[Patents]WITH POWER OR BIAS VOLTAGE SUPPLY
200[Patents] . For plural stage amplifier
201[Patents] . . Filamentary cathodes heated by anode current or anode supply source
202[Patents] . For anode
203[Patents] . . And input electrode
204[Patents] . For input electrode
205[Patents] . . And filamentary cathode
206[Patents] . For filamentary cathode
207R[Patents]MISCELLANEOUS
207A[Patents] . Class D
207P[Patents] . Amplifier protection means


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Last Modified: 6 October 2000