Paraphase amplifier (T389E)

This 6C5 tube circuit was found in a modern tube design manual. The circuit applies to other equivalent triodes.

Powerful current converter (CB5096E)
This circuit can convert an AC voltage signal into a current up to 1 A for powering a load. The...
Continuity Tester (CB4546E)
This continuity tester for low resistances was found in an English magazine from 1978. The circuit...
Liquid Level Control (CB5311E)
The purpose of this circuit is to maintain the liquid level of a reservoir between two values...