Digital FM waves demodulator - has two complementary transistors coupled for low current consumption and low output impedance

摘要

The digital demodulator consists of two complementary input transistors (T1, T2) coupled emitter to emitter and base to base and used to increase the input impedence. The emitter output is coupled to the demodulator itself which consists of two complementary transistors (T3, T4) coupled collector to collector. A voltage divider (R1, R2) is connected between the positive supply pole and the second transistor's base and its tapping is coupled to the base of the first transistor. The output is taken from the collectors and passed over an RC filter. The demodulator has a low output impedance and very low current consumption.