Korg Wavestation seems dead

Synth Repair
1

Hey all,

So Ive been working on repairing a korg wavestation ex. Ive posted a couple times here already. But now I am legitimately stuck. The keyboard seems dead - When I power it on, only the back light of the screen comes on. No text, no audio output, no other sign of life. I tried all outputs, and even using another keyboard with midi out to try to control the wavestation.

What I already did

  1. I replaced the screen. I followed instructions, and have the exact same issue with the new screen as I did with the old.
  2. Took it right apart (not my first time with this keyboard), looked for immediate problems. I checked the components, and they for the most part, they pass the visual inspection.
    * there are some resistors that are heavily corroded/damaged. I metered them and they give the value that they are supposed to be. I do have new ones coming in, though.

What else can I do? Just the screen back light coming on, can that be just a power issue?

Id love to get this going. Its a sentimental item for me.

Thanks!

2

Check the power supply first, and make sure it is putting out the correct voltages.

3

I found the schematics online, and I checked the outputs of the power supply. They seem fine. I’m off my like 5-7% for some, but I think that’s normal.

4

I am guessing this indicates a problem on the main board then, which will be a real job to diagnose. Just to eliminate the easy possibilities, make sure all the connectors are plugged in snugly, and give a bit of a press on the socketed ICs (which are only the EPROMs and the big square IC11 chip).