This simple transistor tester was found in a Japanese magazine in 1967. It tests general purpose transistors of both the NPN and PNP type and is powered by 4 batteries (6 V).
This powerful amplifier with output in complementary symmetry is from an old documentation....
This transistorized oscillator, a modification of the Colpitts oscillator, was found in the...
Found in Popular Electronics from the 90s, this generator uses integrated circuits from that time....