This commercial transistor tester circuit (EICO 666) is from a Japanese publication from the 1960s. The switch selects the types of test with the switching of the terminals and the gain ranges.
This simple photometer uses a 1 mA milliammeter and a common phototransistor. The circuit has its...
The component values depend on the current, which in this case has a maximum value of 5 A. The...
I found this circuit in an article in a 2003 publication. The circuit is an example of how to...