This circuit was found in the April 1971 Radio Electronics magazine. It uses common transistors and can be adapted to use an LED or audible indicator instead of a light bulb.
This 3-transistor timer was found in the January 1994 issue of Electronics Now magazine. The...
This Dimmer circuit for incandescent lamps was found in an English documentation. The input...
With this circuit we can use a high impedance source to excite a low impedance output. The input is...