We found this circuit in a Popular Electronics from the 90s. Transistors can be modern equivalents. Observe the high supply voltage.
The presented logical configuration uses one comparator of the four existing in an LM139 or...
This zero-crossing circuit was found in the 1989 Radio Electronics Experimenter. The Triac must be...
This transformerless low-current power supply circuit was found in the August 1998 issue of...