This simple continuity tester, whose configuration can be found several times on this site, is powered by only 2 batteries providing the indication on an LED.
In the figure we have the way to control a triac of the TIC series with a low voltage through a...
This circuit was obtained in a Radio Shack documentation from 1977. It consists of a didactic...
Found in a 1968 EEE, this circuit uses transistors from that time. The output is 300 ns....