This symmetric 30 mA x 15 V power supply was found in the Ferranti transistor manual from 1974. Transistors are common types at the time.
This circuit from a 2003 documentation, has a protection system that disarms the power supply if...
This circuit was obtained from an old American documentation, and practically any general-purpose transistor...
In the figure we have the circuit of a sweep generator obtained in an old publication. The central...