Korg Poly800/EX800 Users

thetravelsource wrote:
> My Poly-800 works fine on batteries but I have not been able to use the A/C adapter for years. I think someone once fried the circuit with the wrong adapter or polarity and I am wondering if anyone has had a similar problem and knows where to begin to repair. 

Are you sure the power supply is working?  If it's not, then there's 
your answer.  I think they're negative-to-middle, 9V - same as 
Boss/Roland/Kawai, not like Yamaha.

The power connectors on the Poly-800 (and indeed anything that uses that 
type of connector) are usually pretty reliable, but tend to fail such 
that the batteries don't work and an adaptor does!  What happens is that 
there's a pin up the middle for one connection and a springy metal strip 
that touches the outside of the plug when it's in, or another metal 
strip connected to the battery (so it acts as a switch).  The only way I 
can see for the thing to work on batteries but not with a working mains 
PSU is either the pin is broken, or there is a bad solder joint between 
the tag with the pin and the board.

> I am finding it hard to search the group messages via yahoo for similar problems. Perhaps there are no other posts but if someone knows of an answer on this group, please point me to it.

Yahoo Groups search is knackered.  Utterly useless.

Gordon