Vintage Synth Repair

Hello, I've recently acquired a non-functional rev 3 odyssey, and I've been looking for service information for it, but I haven't found much (mostly just some neglected websites with dead links).  I believe this unit might have a power supply issue since it does not power up when it is turned on; the unit has been well taken care of (aside from some dirty sliders) and appears to be in great condition aside from the fact that it won't power up.

I'm interested to see if anyone knows of any working links to a rev 3 service manual or any other advice to troubleshooting this problem.

Thanks, I appreciate any help!

Damon