(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,
24+, for passive coupling networks for wave transmission in general.
