This circuit was obtained in a documentation from the 70s. The operational amplifiers used are uncommon today. Modern equivalent types can be tried out.
This conventional configuration of source stabilized with zener and transistor was found in a...
This RS flip-flop uses two type 4N26 optical couplers and is characterized by the very high...
This is a direction of rotation control for a small motor up to about 2 A with the indicated...