US PATENT SUBCLASS 330 / 76
.~ Compensating for inter-electrode impedance (e.g., neutralization)

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


330 /   HD   AMPLIFIERS

75  DF  SIGNAL FEEDBACK {20}
76.~ Compensating for inter-electrode impedance (e.g., neutralization) {4}
77  DF  .~.~> At least one push-pull stage
78  DF  .~.~> To or from electrode common to input and output
79  DF  .~.~> By transformer feedback
80  DF  .~.~> By coil in parallel to and resonating with inter-electrode capacity

DEFINITION

Classification: 330/76

(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,

319, for feedback used in frequency demodulation noise reduction, and subclass 367 for regenerative feedback in an amplitude demodulator.

331, Oscillators,

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.