This circuit turns off when switch S1 is opened. The circuit is from the 1989 Radio Electronics Experimenter edition; The triac must be controlled according to the load.
The circuit shown is from Motorola's 1990 Linear Databook. Shaded components are optional. The...
This circuit is from an English magazine of 1977. The circuit is still current, just using BC547...
This circuit is from a 1986 Revista Española de Electrónica. It consists of an amplifier with...