This circuit triggers a relay when a light beam that hits the phototransistor is cut off. The circuit is from Electronics Now and the supply voltage depends on the relay voltage.
This circuit shows how to use a Vishay IL4216 or IL12-F optodiac to control a triac in a common...
The circuit shown is from the November 1996 Electronics Now magazine. The basic circuit is in the...
Motors up to 2 A can be controlled by this circuit, which requires a symmetrical source. Although...