This is one of the first radios with an integrated circuit. The circuit is from a Radio Electronics from November 1969. The circuit is powered by a 9 V battery.
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...