Yes the Servo Potentiometer from RS is one such I normally use - but only when the rotation does not exceed 250 degrees or so.

In this case, it will be 4.5 turns in each direction and hence to use the potentiometer solution I need to introduce gearing to reduce the 4.5 x 360 degree to 250 degree. The final resolution will take a hit.

Or wait a minute - can I not use the multi turn pot ? And why not ? Only thing I need to locate a source that has a muti-turn pot with an endurance of 1 million cycles minimum.

Oh great - I feel good.

Thanks Steve.

Raghu