We found this circuit in the 1983 Radio Electronics Special projects magazine. The components are common, and the circuit drives a relay. The power supply must be isolated.
This circuit is used to obtain the synchronized activation of a mechanical battery clock. The...
ON Semiconductor Phototransistor Output Optocouplers Available from Mouser Electronics is the...
Found in an Electronic Design from the 80's, this circuit monitors a three-phase line, activating a...