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363-131 121-55A 14-.5
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Class Number: 330
Class Title: AMPLIFIERS
Subclass Subclass
Number Title
1 R WITH DIVERSE-TYPE ART DEVICE
1 A .With process control system
2 WITH AMPLIFIER CONDITION INDICATING OR TESTING MEANS
3 WITH PLURAL DIVERSE-TYPE AMPLIFYING DEVICES
4 WITH MASER-TYPE AMPLIFYING DEVICE
4.5 PARAMETRIC AMPLIFIERS
4.6 .Traveling wave type
4.7 ..Electron beam device
4.8 .Gyromagnetic type (e.g., ferrite)
4.9 .Semiconductor type (e.g., with semiconductor diode)
5 WITH SOLID ELEMENT WAVE PROPAGATING AMPLIFYING DEVICE
5.5 .Phonon type (e.g., ultrasonic wave propagating device)
6 WITH HALL EFFECT TYPE MEANS
7 WITH CAPACITIVE AMPLIFYING DEVICE
8 WITH SATURABLE REACTOR-TYPE AMPLIFYING DEVICE
9 WITH PERIODIC SWITCHING INPUT-OUTPUT (E.G., FOR DRIFT
CORRECTION)
10 MODULATOR-DEMODULATOR-TYPE AMPLIFIER
11 WITH D.C. REINSERTION CIRCUIT
250 WITH SEMICONDUCTOR AMPLIFYING DEVICE (E.G., TRANSISTOR)
251 .Including Class D amplifier
252 .Including differential amplifier
253 ..Having field effect transistor
254 ..Having gain control means
255 ..Having push-pull amplifier stage
256 ..Having temperature compensation means
257 ..Having current mirror amplifier
258 ..Having common mode rejection circuit
259 ..Having D.C. feedback bias control for stabilization
260 ..Having signal feedback means
261 ..Having particular biasing arrangement
262 .Including push-pull amplifier
263 ..Having complementary symmetry
264 ...And field effect transistor
265 ...And feedback means
266 ...And temperature compensation
267 ...And particular biasing arrangement
268 ....To eliminate crossover distortion
269 ..Having field effect transistor
270 ..Having D.C. feedback bias control for stabilization
271 ..Having signal feedback means
272 ..Having temperature compensating means
273 ..Having particular biasing arrangement
274 ...To eliminate crossover distortion
275 ..Having balanced to unbalanced circuitry and vice versa
276 ..Having transformer
277 .Including field effect transistor
278 .Including gain control means
279 ..And significant control voltage developing means
280 ...With delay means
281 ...With time constant means
282 ..Having feedback means acting as variable impedancee
283 ...Having emitter degeneration
284 ..Having attenuation means in signal transmission path
285 ..Having particular biasing means
286 .Including distributed parameter-type coupling
287 ..Of diode type
288 .Including current mirror amplifier
289 .Including temperature compensation means
290 .Including D.C. feedback bias control for stabilization
291 .Including signal feedback means
292 ..Having compensation for interelectrode impedance
293 ..Having negative feedback
294 ..Having frequency-responsive means or phase-shift means in
feedback path
295 .Including plural amplifier channels
296 .Including particular biasing arrangement
297 .Including particular power supply circuitry
298 .Including protection means
299 .Including combined diverse-type semiconductor device
300 ..Bipolar or unipolar (FET)
301 .Including balanced to unbalanced circuits and vice versa
302 .Including frequency-responsive means in the signal transmission
path
303 ..Including an active device in the filter means
304 ..And equalizing means
305 ..And tuning means
306 ..And bandpass, broadband (e.g., wideband) or sidepass means
307 .Integrated circuits
308 .Including atomic particle or radiant energy impinging on a
semiconductor
309 .Involving structure of three diverse function electrode type
310 .Including plural stages cascaded
311 ..Having different configurations
41 WITH GAS OR VAPOR TUBE AMPLIFYING DEVICE
42 WITH SECONDARY ELECTRON EMISSION TUBE AMPLIFYING DEVICE
43 WITH TRAVELING WAVE-TYPE TUBE
44 WITH ELECTRON BEAM TUBE AMPLIFYING DEVICE
45 .Having electrode coupled to cavity resonator
46 .Having deflecting means
47 WITH MAGNETICALLY INFLUENCED DISCHARGE DEVICE (E.G.,
MAGNETRONS)
48 .Having signal applied to magnetic means
49 WITH VACUUM TUBE HAVING DISTRIBUTED PARAMETER IMPEDANCE
CHARACTERISTICS
50 WITH DUMMY TUBE
51 COMBINED WITH AUTOMATIC AMPLIFIER DISABLING SWITCH MEANS
52 WITH PILOT FREQUENCY CONTROL MEANS
53 WITH DISTRIBUTED PARAMETER-TYPE COUPLING MEANS
54 .Distributed amplifier
55 .Push-pull
56 .Waveguide, cavity, or concentric line resonator
57 .Artificial line
58 WITH ROTATING DYNAMOELECTRIC AMPLIFYING DEVICE
59 HAVING LIGHT-CONTROLLED OR ACTIVATED DEVICE (I.E., NOT LIGHT
SIGNAL)
60 HAVING MAGNETOSTRICTIVE-TYPE AMPLIFYING DEVICE
61 R WITH RESISTIVE-TYPE AMPLIFYING DEVICE
62 .Magnetoresistive type
61 A .Negative resistance amplifierss
63 WITH MAGNETIC MEANS AMPLIFYING DEVICE
64 WITH SPACE CHARGE GRID TUBE
65 INVOLVING STRUCTURE OTHER THAN THAT OF TRANSFORMERS PER SE
66 .With printed circuits
67 .With capacitive structure
68 .With shielding means
69 SUM AND DIFFERENCE AMPLIFIERS
70 ANODE ENERGIZED THROUGH DISCHARGE PATH OF CONTROLLED VACUUM
TUBE
71 .Plural discharge paths traversed by anode supply
72 ..Amplifier devices in arms of a bridge
73 .Plural outputs
74 .Separate signal inputs to series devices
75 SIGNAL FEEDBACK
76 .Compensating for inter-electrode impedance (e.g.,
neutralization)
77 ..At least one push-pull stage
78 ..To or from electrode common to input and output
79 ..By transformer feedback
80 ..By coil in parallel to and resonating with inter-electrode
capacity
81 .At least one push-pull signal stage
82 ..Positive and negative feedback
83 ..Including D.C. path for signal feedback
84 .Plural amplifier channels
85 .Amplifier in signal feedback path
86 .Variable impedance in feedback path varied by separate control
path
87 .Cathode impedance feedback
88 ..Cascade amplifier stages with cathode-cathode feedback
89 ...Between adjacent stages
90 ..Combined with diverse-type feedback coupling
91 ...Diverse feedback to or from cathode
92 ....Feedback to cathode impedance of a prior stage
93 ...Including positive feedback
94 ..Frequency responsive means in cathode impedance feedback path
95 ..Nonlinear impedance means in cathode impedance feedback path
96 .Combined with control of bias voltage of signal amplifier
97 .Including D.C. path for signal feedback
98 .In cascade amplifiers
99 ..Multiple feedback
100 ...A feedback to input of a prior stage
101 .Positive and negative feedback in same path at different
frequencies
102 .Current and voltage feedback
103 .Multiple feedback paths
104 ..Positive and negative feedback
105 .From impedance in series with output load (e.g., current
feedback)
106 .In series with input source
107 .Phase shift means in loop path
108 .Potentiometer common to signal and feedback path
109 .Frequency responsive feedback means
110 .Nonlinear impedance element in loop path
111 .To or from an auxiliary grid or to the anode
112 .Positive feedback
113 POLYPHASE POWER SUPPLY (I.E., FOR AN ELECTRODE, CATHODE HEATER,
OR FILAMENT))
114 UNRECTIFIED A.C. POWER SUPPLY FOR AN ELECTRODE (I.E., NOT THE
HEATER)
115 .Applied to filamentary cathode
116 WITH BALANCED-TO-UNBALANCED COUPLING
117 WITH UNBALANCED-TO-BALANCED COUPLING
118 INCLUDING A PUSH-PULL STAGE
119 .Coupling to or from cathode in push-pull
120 .Interstage coupling between push-pull
121 ..D.C. coupling
122 .Input and/or output coupling for push-pull
123 .Power or bias supply circuits and control thereof
124 R WITH PLURAL AMPLIFIER CHANNELS (E.G., PARALLEL AMPLIFIER
CHANNELS)
125 .D.C. and A.C. amplifier channels
126 .Amplifying different frequencies in different channels
124 D .Redundant amplifier circuits
127 WITH CONTROL OF POWER SUPPLY OR BIAS VOLTAGE
128 .Control means for anode of screen grid circuit
129 .With control of input electrode or gain control electrode bias
130 ..Bias controlled by separate external control source
131 ..Control of bias on separate gain control electrode
132 ..Frequency selective means to select control signal from
amplifier channel
133 ..Different bias control means for different stages of cascade
amplifier
134 ..Plural different bias control voltages provided by separate
means
135 ..Amplitude limiting or bias voltage
136 ..Bias control signal from input of amplifier
137 ..Oscillator supplies or controls bias
138 ..Bias controlled by biased rectifier or discharge device
139 ..Electronic tube controls bias
140 ..Rectifier in bias control circuit
141 ..Time constant circuit in bias control circuit
142 ..Cathode resistor supplies bias (e.g., self-biasing circuits)
143 THERMALLY RESPONSIVE IMPEDANCE
144 VARIABLE IMPEDANCE FOR SIGNAL CHANNEL CONTROLLED BY SEPARATE
CONTROL PATH
145 .Electron tube or diode as impedance
146 WHEATSTONE BRIDGE WITH AMPLIFIER IN AT LEAST ONE ARM
147 PLURAL SIGNAL INPUTS
148 PLURAL SIGNAL OUTPUTS
149 HUM OR NOISE OR DISTORTION BUCKING INTRODUCED INTO SIGNAL
CHANNEL
150 CASCADED SIMILAR AMPLIFYING DEVICE OF DIFFERENT CHARACTERISTICS
151 WITH AMPLIFIER BYPASS MEANS (E.G., FORWARD FEED)
152 CASCADED DIFFERENTLY COUPLED BETWEEN STAGES
153 .Including a cathode follower stage
154 .Transformer or resonant circuit in interstage coupling (e.g.,
stagger tuning)
155 UNICONTROL OF COUPLING OR THE CIRCUITS ASSOCIATED THEREWITH
156 BOOTSTRAP COUPLING
157 INTERSTAGE COUPLING
158 .Coupling to cathode
159 ..D.C. coupling
160 .Coupling to plate or auxiliary grid
161 ..D.C. coupling
162 .Output coupling from gridd
163 ..D.C. coupling
164 .With electronic tube or diode in coupling circuit
165 .Transformer coupling
166 ..With additional reactive coupling
167 ..With additional impedance connected to "P" or "S" circuits
168 ..From cathode
169 ..With means for adjusting inductive coupling
170 ..With shielding
171 ..With transformer structure
172 .Coupling from cathode
173 ..D.C. coupling
174 .With electromechanical transducer (e.g., piezoelectric
crystal)
175 .With lattice or Wheatstone bridge network in coupling circuits
176 .With T, H, or Pi network in coupling circuit
177 .With coupling or blocking capacitor
178 ..With R or L in series between stages
179 ..L in anode or grid circuit
180 ..With R in anode and grid circuit (RC coupling)
181 .D.C. coupled
182 ..With series reactive element between stages
183 ..With nonlinear device
184 ..With series resistance between stages
185 INPUT NETWORKS
186 .To cathode
187 ..D.C. coupled
188 .Transformer coupled
189 ..With additional impedance connected to "P" or "S" circuits
190 ..With transformer structure
191 .D.C. coupled
192 OUTPUT NETWORKS
193 .From cathode
194 ..D.C. coupled
195 .Transformer coupled
196 ..With additional impedance connected to "P" or "S" circuit
197 ..With transformer structure
198 .D.C. coupled
199 WITH POWER OR BIAS VOLTAGE SUPPLY
200 .For plural stage amplifier
201 ..Filamentary cathodes heated by anode current or anode supply
source
202 .For anode
203 ..And input electrode
204 .For input electrode
205 ..And filamentary cathode
206 .For filamentary cathode
207 R MISCELLANEOUS
207 A .Class D
207 P .Amplifier protection means