This circuit was found in a 1970 IEEE publication. The circuit functions as a voltage controlled variable resistor and can be used with audio signals. Transistors admit current equivalents.
This circuit was found in an American 1980s documentation. The components are current but most...
This simple timer for incandescent lamps or other non-electronic charges uses a triac as a control...
Found in a Radio Electronics store from the 90s, this circuit acts on the alternator. The circuit...