Two transistors on a regenerative switch are used to trigger a triac. This circuit is from the RCA Power Circuits manual. Transistors admit equivalents.
We found this circuit in the 1982 Selezione Radio magazine in Italy. The circuit uses an...
This circuit was obtained from Dutch documentation from 1967. It uses transistors of the time...
This circuit was found in a 1966 General Electric book. The triac and the day are from that time...