Pulse-Frequency Modulator,

The pulse-frequency modulator based on a symmetric triggered multivibrator with RC-couplings using two transistors whose bases are connected to the sources of triggering currents, and whose collector loops contain clamping diodes to sustain transistors in the operating range differs in that to extend the modulation frequency range in the soft self-excitation mode and to reduce the effect of spread and variation of the transfer coefficients of the multivibrator transistors in the modulation frequency range, self-induction coils are connected between the points of connection of the timing capacitors with the transistor collectors and the points of connection of collector load resistances with the clamping diodes.