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.
MCP19124/5 Contains Independent Voltage and Current Control Loops Plus a Full Suite of...
This circuit is designed to control static loads fed by direct voltage. The circuit is from...
This circuit is from an American 1964 documentation. Transistors of the time are used, but modern...