This circuit for incandescent lamps was found in the February 1972 Radio Electronics magazine. The triac is rated according to the lamp power and the sensitivity adjustment is made in R1.
This circuit was obtained from an American documentation from the 1980s. The T1 triggering...
Found in a 1974 Ferranti manual, this circuit uses diodes to limit the voltage on the transistors. The...
This circuit is from an English publication of 1991. With it you can use a common multimeter on...