Archive of the former Yahoo!Groups mailing list: Korg Poly800/EX800 Users

Hi,

I bought a Poly800 last week which worked: I was able to load the factory presets via a .wav file and most of the keys worked.  I repaired the keys by cleaning the contacts.

While I had the synth open I decided to apply a battery modification which I found at this location  http://analog.no/cms/index.php?option=com_content&view=article&id=50&Itemid=49

I confirmed all of the connections and tested them using my multimeter.

This mod is not the same as the one I've now discovered in the file section. 

I removed C87, C88, D23 and D15. I bridged the trace at D15 and cut the trace close to C106

I have not touched R1 or D1

This is a Mk-1 Poly800 which didn't come with a memory backup battery.  There are two 'pads' where the battery holder can be soldered.

When I powered up the synth it started ok and I made a simple patch to test that all the keys worked.

I then tried loading the factory presets from a .wav file played back from my phone.

The tape load failed and when I re-started the synth I got the error message 1.8 50 01 on the display (see attached image.

I'm puzzled as to whether something corrupted when I tried loading the factory presets or have I fried something while soldering?

I put all of the removed components back into the synth and re-bridged the cut trace.

The synth is still showing the same error message.

Any suggestions on what I might try next?  I'd like to try resurrect the synth and fix whatever I've done.

thanks,

Peter