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.
We found this circuit in a Popular Electronics of the 90s. The MOSFET can be of any type,...
In fact, the correct name would be a hearing aid amplifier. However, we use the name of the...
This circuit controls a relay causing it to open and close its contacts at a speed that depends on the...