Figure shows the FM demodulation circuit 567. Figure, the FM signal from the 3 pin input, demodulated signal output from 5 feet. Circuit can demodulate the FM signal center frequency is:
fo = 1.1/RC
The figure, C1 for the filter capacitor, C2 is the bandwidth to adjust the capacitor, C2 is reduced, increased demodulation bandwidth demodulator. Basis for the choice of C2:
Generally take C1 = C2.
The circuit also indicates demodulation circuit. When the correct demodulation, the 8-pin output low. Connected to the indicator, the indicator light, but also to remove it, as a control signal used.