Found in a 1960s RCA documentation, this circuit applies to most common triacs. The trigger device is a neon lamp and the sensor is an LDR. R is typically 100k and C is 220 nF.
This interesting configuration, named after its developers, multiplies the secondary voltage of a...
We found this circuit in an English publication in 1981. It can be improved by exchanging T1 for a...
This two-channel wired intercom was found in the April 1990 issue of Radio Electronics magazine....