A friend of mine said that he had at one time used a stepper motor and a couple of IC's to provide a digital output of shaft position.

Is there anyone out there that is familiar with this circuit and components?

Thanks,
Michael

 

He was probably using a stepper as a generator (alternator), tied into a comparator and a counter to count the pulses.

Not a very reliable way to do it, as if the shaft were rotated very slowly, the pulse generated may be too low of an amplitude to be detected. Also, a stepper used as a sensor would add considerable inertia and drag to the shaft.

Better to use a rotary encoder.