DUAL LOOP RECEIVER TUNING AND FREQUENCY TRACKING SYSTEM

摘要

A first servo loop responsive to the beat frequency produced in a receiver automatically tunes an oscillator coupled to the input circuit of the receiver to the receiver frequency. A second servo loop then tunes the receiver to desired frequencies within the receiver band, while the oscillator automatically tracks this tuning. The second loop may include a comparator for comparing voltages indicative of the frequencies to which it is desired to tune the receiver with a voltage employed for tuning the oscillator.