NPN and PNP transistor tester (CB22146E)

This simple transistor tester was found in old English documentation. Suitable for general purpose transistors.

9V Eliminator (CB23752E)
This 9 V battery eliminator was found in Radio Electronics magazine from June 1966. The transistor is of...
Ultra Long Period Timer (CB25049E)
Using the ZN1034E which reaches 19 days interval, this is a simpler circuit which can be...
Millivolt Meter LM356 (CB25227E)
This analog meter circuit was found in the September 1989 issue of Radio Electronics magazine. The source...