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.
In this circuit of 1987 the player has to briefly press one of the keys trying to hit which LED...
EZP-Q metallized polypropylene capacitors from Panasonic's can be purchased from Mouser...
This circuit has two high-impedance inputs. The gain is high and more inputs can be added. Use a...