I fixed this unit for my turning club before checking the motor - it turns out the motor was also toast, so we didn't fix the lathe, and I have this controller left over - it may do someone here some good - it will control any small DC motor that is similar to the motor on the Jet, or of course if you have a Jet with a sick controller it could be your ticket....
Here's the link - be sure to put the whole thing on one line.
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There is a moral here, by the way - the unit was damaged by being plugged into 220 instead of 110 - one of the club members was hosting a tutorial and had wired his house using 110 outlets for 220 instead of sticking to the special 220 outlets. the moral is, don't do that.