Trionics Model 50 DRO schematic?

I recently bought a J head Bridgeport at an auction with an
ancient DRO on it. It's a Trionics Model 50. The display powers up,
but nothing happens when x or y axis are moved. The mill was pretty
cheap ($800 with working table power feed) so I won't be bummed if I
cannot get the DRO to work, but I was wondering if anyone on this
group might have a schematic for this unit??

Thanks for any help, Howard Crothers