We present the circuit of the commercial transistor tester Sanwa SC2 sold in Japan in the 1960s. The circuit has several scales and types of test being powered by a 22.5 V battery.
This very simple circuit uses a phototransistor and a very sensitive relay (reed type) being used...
We found this circuit in Radio Electronics magazine from January 1958. It uses a neon lamp as the...
The integrated circuits in this application are not very common today. One consists of an A / D...