[Al Skierkiewicz]

Yarden,
The encoders have a specific frequency limit. You have to choose the encoder wheel that matches your rotational speed. If you are looking for too great a resolution at too high a speed, the encoder produces no output. I have also heard that there were some encoders that were shipped this year from the manufacturer that may have a defective component. I don't have that information at hand but perhaps someone else will post on that issue.