Geiger counter with high voltage source (CB22333E)

This circuit includes a high voltage inverter to power a Geiger tube. We found it in an American documentation from the 60s.

Two-Wave Radio (CB16395E)
This circuit in a receiver that allows the capture of distant stations with short waves. The...
Simpson 250 Multimeter (CB1401E )
This was a very popular instrument in the workshops of the 60s and 70s. It was a "top of the line"...
MOSFET Constant Current Source (CB19953E)
This source is more elaborate than the previous one because it uses two transistors. The source is...