Based on CMOS logic this short-circuit locator circuit uses the ear's ability to detect small changes in pitch, which are caused by variations in millivolts in a track under analysis.
We found this simple transistor tester in a French publication in 1981. It uses a common analog...
Who is faster? or reaction game are other names for this circuit that we find in old...
This circuit is from an 80's component manual. The components are from the time, but the circuit...