This circuit is from an old American documentation from the 70s. Transistor 2N3904 can be replaced by BC548. The relay must have 100 mA of maximum current.
This circuit was obtained in an old American manual. The circuit is valid for any operational. The...
Using a 74123 TTL this circuit was found in the Radio Elecronics magazine of June 1975. The power...
Suggested by Sprague in the 1980s documentation, this circuit can control three-phase AC motors....