We found this circuit in the 1974 Ferranti transistor manual. Transistors are from the time, being general purpose types.
For experiments with ionization chambers and Geiger valves this circuit generates high voltage from...
This control allows to start or stop a motor up to 3 or 4 A with a low intensity signal. The...
The battery is charged by the photocell that keeps the low consumption beacon in the dark. The...