Korg Poly800/EX800 Users

Hi Moe,

How did you go working on your Poly with the weird display problem?
Reason I ask is that I pulled out of storage my most beat up Poly 800
and discovered that it has a very similar problem.

In my case, when I power up the Poly the display immediately shows "7-
P". So it looks like the 7 button is stuck down. Also, if I set the
sequencer enable switch on the back then power up the keyboard it also
displays "11 50 01".

So I think I have a problem that is very similar to yours. I know that
the 7 switch is not stuck because I swapped out the main board into my
EX-800 and it still does the same thing.

So over the next week I will be looking closely at that main board.

Does anyone else have any history with the display behaving weird in a
similar way?

Mike.

--- In korgpolyex@yahoogroups.com, "m.sislack" <m.sislack@...> wrote:
>
> --- In korgpolyex@yahoogroups.com, "korgpolyex800" <korgpolyex800@> 
> wrote:
> >
> > 1.8 in the left display is not sequencer edit mode, that's for sure.
> > 
> > If you turn the keyboard you should get 11 P. Then, if you switched to
> > sequencer edit mode the display would change to 11 50 01.
> > 
> > So it seems you have a more serious problem than just stuck switches.
> > 
> > Does the keyboard make sounds when you hit keys? If yes, do all of the
> > keys work, or just some of them? Which ones?
> > 
> > Mike.
> > 
> Hello Mike!
> 
> In deed it seems to be a more serious problem. Ehen switches on, in the 
> display is shown "1.8 50 01", but theres no reaction to key-hits or 
> pressed buttons, not even to the switches on the back. Only when VR1 is 
> turned, the machine awakes and starts to make weird noises like 
> uncontrolled key-hits and noise with cut off-modulations. This is why I 
> wonder if the problem might be caused by any dead transistors Q1, Q2 or 
> maybe Q18.
> 
> moe
>