DX7IIFD No Power :(

Hello syntaur forum, this is my first post.
I am having trouble with my dx7…
I turned it on after a few months and it worked fine. I turned it off and a few hours later it wouldn’t turn on anymore. I opened it and the fuse is ok. Internal Battery is also ok. anyone have any ideas on what else to check? Or does anyone have a power supply circuit For sale? Thanks!

My DX7IID had the same issue. It turned out it was the larger, main capacitors in the power supply had gone bad. I replaced those and BINGO! Had it working in no time.

How did you figure this out, I have a DVOM, but I’m not very good with component testing/soldering.
I did disconnect the board from the rest of the synth before checking diodes…

As long as the power is disconnected, you can try measuring the resistance across the main caps. If you get a low reading, they are most likely shot. Keep in mind that because they are still in-circuit, this isn’t a foolproof method. If I recall, they were a pretty common cap, so replacing them “just in case” wouldn’t hurt.

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