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 thermal control circuit appeared in Radio Electronics magazine in October 1958. The circuit is...
This small medium wave radio was manufactured in the 1960s in Japan. The circuit is powered by 4...
This circuit is from a 1988 publication. It makes use of an LM3914 LED driver circuit, still...