This circuit is intended for detecting 3 levels power grid voltage, and it can be adapted to operate with the most diverse voltages. The circuit uses neon indicator lamps.
This circuit that generates signals between 1.5 and 2 kHz was found in a documentation from the...
Found in a 90s Popular Electronics, this touch switch uses a single sensor. PLLs are common today....
This low current converter was found in the January 1997 issue of Electronics Now magazine. It is...