Other versions exist on this site from various publications. This one is from the Radio Electronics Experimenter from 1990. The bargraph circuit uses the UAA170.
The circuit shown in the figure uses a programmable unijunction transistor (PUT) of the BRY39 type...
This circuit was sent by reader and collaborator Adriano Muniz Moura from Pirapora – MG. The...
This remote control for resistive loads using a triac appears elsewhere on this site. The circuit...