Based on Radio Shack 276-137, this circuit was found in the December 1995 issue of Electronics Now magazine. The circuit drives an LED but could use a relay instead.
This circuit is based on the voltage drop of the diodes in conduction, in the order of 1.6 to 1.7...
This protection circuit trips by quickly blowing the fuse in the event of an overcurrent. The circuit is...
We found this circuit in an English publication from 1963. The circuit uses germanium transistors of the...