Just bought a poly 800 of the 1st revision. This model does NOT have an internal backup battery inside.

It was working fine for a couple of days (love it !!!), used it with batteries first, then started to use a power supply (not the original one but it worked fine for 2 days).

Then, as I turned it on again, the display showed weird signs for a couple of seconds and jumped back to "P11". No sound. Frozen. From then on, no single button/knob would work anymore - the display either shows some weird signs or "P11" but doesn't change from there, no matter what I push. The synth basically doesn't react to anything at all. If I turn the volume up it just makes click click click.....
I opened the synth, it was a little dirty but I cleaned it and I cannot see anything missing or broken (I am not an electrician though

Anybody can tell me what might be wrong ? Could my power supply have damaged something, and why ? What can I do ?

I'd appreciate any help, thanks a lot !
Bernard

First off, ALWAYS keep batteries in the thing. That reduces the chance of power dropouts and memory flakes. That said:

Two possibilities:
A.)Take it back apart and re-seat any socketed chips. Using a jewelers screwdriver, pry up each end of each chip until its about halfway out of its socket. Then, providing support, press the chip back in. If that does not work, keep reading.

B.)see if you cant get a nice person with an eprom burner to get the poly 800 hex bin file and burn you a new eprom. You may have to go to a college that has an electronics course.

It only takes a half hour at most, and chances are your original eprom can be erased and reprogrammed, so you will not have to buy a new one.

Remember that chip scene on the plane in the 1985 movie "Real Genius?" You will get to see that live.

after 20-odd years, eproms DIE.

If that doesn't fix it, keep the keyboard, filter(it'll be the chip that says 2069AD on it), and joystick out of it. Those are the juiciest bits in the korg replacement part catalog.

It seems, by digging through my archives, that I have the poly 800 hex bin file. This is the vital data the poly 800 needs to function. Tell me where to send it if all above fails. You will need it before you begin your quest.

[This message has been edited by Justin Gazda (edited 06-29-2007).]

Thanks a lot, Justin ! I am out of town but will check what you said as soon as I'm back in my studio next week. I'll let you know if I need the poly 800 hex bin file.
thank you so much ! Bernard


[This message has been edited by bernardguillaume (edited 07-06-2007).]

Can You help me ?
Im looking for oryginal eprom data for poly-800

Thanks for any help ,
moobik
moobik@go2.pl

Yes you can find the ROM binary here http://synthzone.com/midi/korg/poly800/ROM800.ZIP

It looks like this zip has both the Poly 800 and EX 800 ROM binaries.

hello

Thanks For links
but
In zip file is file that has a 22kb ,but in poly-800 is MBM2764-8kb . I have my dump from this eprom ,but i dont know is this ok
I looking for dump from poly-800 eprom mbm2764
If anyone wants I can send my dump to look .

Thanks,
moobik