This circuit was found in an old GE manual. It uses a thermocouple as a sensor. The SCR must be in accordance with the power of the controlled load.
This circuit appeared in the 1991 Electronics Experimenter Handbook. The circuit is for remote...
This circuit was found in Radio Electronics magazine from January 1959. The power transistor must...
This circuit uses an MW radio tuned to around 540 kHz to detect atmospheric signals, for example, from...