These 6 to 12 V source with current up to 100 mA was found in Radio Electronics magazine from June 19666. The source has a current indicator and uses transistors of the time.
This phase inverter with transistors, used in audio amplifiers, was found in a French publication from...
With the illustrated circuit we can run a DC motor in one direction or the other, depending on...
Motors up to 2 A DC can be controlled by this circuit that we find in the manual for linear...