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 circuit was found in an English documentation from 1989. The transistors support...
This relay driver or relay shield for relays up to 100 mA can operate with voltages from 9 to 12 V...
With this circuit it is possible to fire an SCR from the light that falls on a phototransistor. The circuit...