This 10-minute timer was found in the July 1994 Radio Electronics magazine. The relay must be sensitive to the supply voltage used. The capacitors determine time ranges.
The purpose of this circuit is to amplify the signal of a medium or high impedance microphone,...
Taking advantage of the two stable states of a tunnel diode it is possible to build a switching circuit...
We found this circuit in a 90s Electronic Design. The components admit current equivalents. The circuit...