(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
115, 123 and 162 through 166 which are directed to devices involving amplification.
307, Electrical Transmission or Interconnection Systems, 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,
13+, for nonlinear resistor elements.
361, Electricity: Electrical Systems and Devices,
271+, for structure of a capacitor which may be nonlinear.
