So he decided to replace the stepper motor controller in his turntable and ... the impressively deep throttle capability of the new driver.

[Ken]’s Easy Stepper Motor Controller is a much simpler solution to the problem of testing these drivers and could, with a bit of practice, be constructed on a single-sided homebrew PCB.

Stepper motor drives are devices used to power and control stepper motors. While some basic drive units only supply power, many commercially available drives also incorporate controller electronics ...