This 80's circuit turns off a TV or other appliance after a set time. The base is a 555 IC and the relay is according the supply.
This circuit was found in a 1965’s General Electric documentation. It is intended for low voltage...
This protective circuit for power lines was found in a Radio Electronics from November 1957. The...
Found in the March 1974 Radio Electronics magazine, this circuit is designed to measure the level...