We found this circuit in a publication by General Electric in the 1980s. The transistors and the PUT are from that time. The control is done by a tachometer based on an optical coupler.
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...