CRYSTAL CONTROLLED VARIABLE FREQUENCY OSCILLATOR

摘要

A crystal oscillator frequency and a shift oscillator frequency are selectively combined in a PUT and TAKE circuit comprising digital dividers and logic gating for generating an output signal at a center frequency, at a high frequency and at a low frequency. The center frequency is governed by the crystal oscillator, the high and low frequencies are determined by the center frequency plus and minus the shift frequency of the shift oscillator.