This silencer or squelch preamp circuit was found in a documentation for radio amateurs. It completely mutes the circuit when there is no sound picked up by the microphone.
This good amplifier with output in complementary symmetry is from an old publication, and modern...
The integrated circuit used is a voltage reference from Motorola. This configuration was obtained in...
This circuit was obtained in a magazine Hands On-Electronics from June 1987. It is a circuit that...