This circuit uses two relays that switch when the voltage exceeds the value given by zener D2. The circuit is from a Radio Electronics magazine from April 1975.
This power supply was specifically designed for the CB18749E transmitter, but it is suitable for...
This circuit was found in the November 1992 issue of Radio Electronics magazine. The circuit has...
Designed to operate with a video camera, this small transmitter was found in the February 1993...