AUTOMATIC FREQUENCY DEVIATION CONTROL DEVICE Russian patent published in 1999 - IPC

FIELD: radio engineering. SUBSTANCE: device has quartz-crystal pulse generator, frequency divider, controlled standard oscillator, frequency signal adder, frequency-to-voltage converter, frequency subtraction digital unit, pulse shaper, low-frequency filter, ac amplifier, analog subtracter, controlled entity (local oscillator), and reference voltage supply. Adder circuit incorporates single-shot multivibrator, majority element, and D flip-flop. Stabilization of frequency deviation is effected due to correction using results of digital comparison of controlled entity and controlled oscillator frequencies. In order to eliminate effect of superposition of frequency signals, adder incorporates provision for uniform synchronization of D flip-flop at double frequency. EFFECT: improved stability of frequency deviation in frequency modulators. 2 cl, 3 dwg