This is the circuit for the HM-10ª, an instrument sold by Heathkit. The circuit is from a Radio Electronics from May 1963. The indication is by an analog instrument.
This transistor tester circuit has the advantage of using a constant current source in the tests....
This circuit is from a 1977 publication for radio amateurs presenting a crowbar protection. The...
Suggested by a 1968 documentation, this circuit limits the current of a regulator and can be...