Radio receiver storage of station parameters - has capacitance diode tuning mechanism and variable potentiometer

摘要

Voltage from a fixed transmitter potentiometer and from a variable potentiometer are applied to a comparator whose output voltage controls a d.c. voltage setting motor. The voltage setting motor moves the fixed sender potentiometer until its voltage is equal to that of a variable potentiometer. The output voltage of a comparator (24, 26, 32, 33, 35, 34) is applied to a selected setting motor (5, 6). It is proportional to the input difference voltage, and its polarity determines the motor direction of rotation, and its magnitude the motor (5, 6) speed.