We found this circuit in a Radio Electronics issue from July 1969. The lamp remains on until C1 opens. The time is given by capacitor C1.
This circuit for incandescent lamps was found in a 70s documentation. The circuit uses an SCR...
This circuit is from an Elementary Electronics from 1977. It can be assembled with relative ease...
This circuit detects the presence of strong signals from spy transmitters, enabling their...