This circuit was obtained from Linear Technology documentation from the 80's. Powered by 5 V it can be used as a shield. The components are from the era.
This circuit is a modification of the previous one, also found in the July 1995 Electronics Now...
Being able to operate with frequencies up to 100 kHz, this circuit was found in a 90’s...
We found this simple transistor tester in a French publication in 1981. It uses a common analog...