This circuit was found in documentation from the 1980s. It is powered by the audio signal that must be cut. Transformers are the critical components and transistors are 2N2222.
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...