Possibly the Opt-Isolator of the MIDI input is blown?
Inside the Poly-800 it's a PC900, guess it's the same in the ex800...
I'd try to replace it.
r.
--- In korgpolyex@yahoogroups.com, "ariebruus" <ariebruus@...> wrote:
>
> Hi there,
>
> my ex800 is broken. It started with total failure but this site helped me to get the +5v en -5v back on the board (thank you all). Now the display is functioning like it used to. At first there was no sound but that was because of all the parameters being low. I was able to load some settings thru the tape interface. The're also some notes in the sequencer so i know the machine is able to produce sound (just by pressing start/stop). But now the problem: the ex is not responding to midi. It looks like there is no way to communicate via midi anymore. Are there some things i could try to repair my little friend?
>
> Thank you in regard,
> Arjan, Amsterdam
>