Abstract: A variable inductor includes a coil, a moveable contactor, and moveable magnetic material caused to move proximate the coil and simultaneously with the contactor. The contactor establishes first and second portions of the coil and, relative to the condition using no magnetic material, the inductance of the first portion is increased while the inductance of the second portion is substantially unchanged. Thus, over substantially all the tuning range, the first portion inductance is maintained greater than the second portion inductance.

Abstract: A variable inductance includes a coil and a moveable contactor which maintains continuous contact with the coil. An electrical connection, which is moveable along with the moveable contactor and away from a first end of the coil, connects the moveable contactor with further contact means positioned remote from the first end of the coil.

Abstract: As part of a moveable carriage assembly, a plurality of trolley wheels are capable of being driven, in worm-gear fashion, along a coil which is rotatable about its axis. One end of the coil is conductive and the other end of the coil is preferably non-conductive. A further part of the traveling carriage assembly electrically interconnects a conductive trolley wheel with an electrical contact situated remote from one end of the coil. Multiple conductive wheels are electrically interconnected.

Abstract: A plurality of moveable contactors may travel along a rotating coil, one end of which is conductive and the other end of which is non-conductive. Two or more electrically interconnected moveable contactors effect a shorting across unused electrical turns and thereby affect unused coil portion resonance. For tuning conditions where very little of the coil is unused, the non-conductive coil portion serves as a sidetrack onto which one or more contactors can move and acts as a mechanical storage or memory for preserving relative positions between contactors.

Abstract: An intermodulation distortion limiter controls the ratio of average power to peak envelope power in the output of a linear power amplifier and this protects against excess non-linearity by reducing the drive power when the ratio exceeds a similar ratio associated with the incoming RF signal.