Circuits similar to this can be found in this section. This is from 1967 General Electric documentation. The main SCR must be fitted with a heat sink.
This circuit was obtained from an English publication from the 70's. The circuit is still current for...
This circuit makes use of an unusual Analog Devices component today. The circuit is from a 90's...
This circuit was found in a 1974 documentation. The bipolar transistor can be the BC548 and at the...