Found in a 90's EDN, this circuit controls both the speed and the direction of rotation of a stepper motor. Relays can be replaced by MOSFETs, with circuit adaptations.
This circuit is from the time when photos were revealed in darkrooms. We found it in a 1968...
This is a commercial circuit that can be found in several publications from the 80s and 90s and...
April 2017 - Mouser Electronics already has in stock the new HMC8400, Analog Devices low noise...