This circuit for incandescent lamps was found in the January 1980 Radio Elecronics magazine. The sensitivity can be controlled by a potentiometer and the microphone used is of the dynamic type.
This electronic roulette circuit with 10 numbers was found in a Popular Electronics from the 80s....
This circuit has a very high input impedance and a very low output impedance. We found it on a...
This circuit is from an English documentation from 1969. The circuit can be designed based on...