Diode Tester (CB22137E)

This diode tester was found in an English publication from the 1980s. Transistors are general-purpose types of the time.

Complementary Transistors Monostable (CB19362E)
Equivalent transistors, like the BC548 and BC558 pair can be used in this circuit that we find in an...
Turns Counter (CB18037E)
This is a project that can easily be adapted for other purposes such as counting people, objects,...
High-speed buffer (CB9556E)
Found in a 1980s documentation, this circuit makes use of components from that time. Modern...