Recommended for automotive applications, this circuit was found in an April 1982 Radio Electronics magazine. The transistor supports equivalents. Sensitivity adjustment is made by R1.
This transformerless power supply uses an SCR as a regulator. It was found in a Popular...
This circuit was obtained in a documentation from the 90's. Several common operational amplifiers...
We found this circuit in an old Popular Electronics. The circuit is experimental, driving an LED...