Korg Mono/Poly

It works now! Here's what happened tonight, I changed the volume pot 
to a new one (I had ordered a replacement a few years ago, never got 
around to installing it) and it didn't fix the problem.

Then it occurred to me after messing with this for a bit, that it 
might be the MIDIJACK I installed on this last year - sure enough, 
one of the wires had come disconnected. Reconnecting it solved 
everything! 

So there was nothing wrong with my Mono/Poly, only the wiring for 
MIDIJACK kit I had put in. This whole ordeal at the very least got me 
to change the potentiometer, and learn a bit of troubleshooting. 
Thanks for your help Florian, I appreciate it. 

I also decided to purchase the Korg Legacy 2007 collection, since I 
don't own any official emulation synths. It will be nice to have a 
backup if one of these go down again. It just kind of makes sense to 
perform with a controller and laptop, this synth belongs in the 
studio, less gigging with it means less repairs. I just hope the 
software version sounds pretty good, I imagine it does!

Working with the Mono/Poly and Polsix has been taxing because of 
frequent repairs (and I cannot afford to ship them out for 
professional work) but still very gratifying. The only thing that 
bothers me about the Polysix is the key contacts, I've tried multiple 
repair techniques without a solid fix. I tried a few methods, one 
recently which worked great for a month or two, and now a number of 
the keys are back to not playing, or intermittent. I also used the MG 
Electronics keypad repair kit, which worked great on my Mono/Poly, 
still working 10 years later with no key dropouts, but the Polysix 
for some reason has always had a problem. 

Anyways, I'm so glad it's working again. Back to normal. 

Rich



--- In korg_mono-poly@yahoogroups.com, "hoggybogger" 
<hoggybogger@...> wrote:
>
> Thanks for the reply Florian - I am wondering where to measure on 
the 
> low/mid/high switch, there are eight points - do I just choose any 
> one of the four pairs and do them across? 
> 
> I'm confused on how to measure the VCA out and VCF out testpoints, 
> would I be looking for some kind of voltage reading, or is that for 
> placing the output to an amp like an audio cable to test for sound?
> 
> Thanks again for your help, I will have a chance to test some 
things 
> out when I get out of work in around five hours.
> 
> Rich
> 
> --- In korg_mono-poly@yahoogroups.com, Florian Anwander 
> <fanwander@> wrote:
> >
> > Hi
> > 
> > hoggybogger schrieb:
> > > The only sound I seem to be able to get out of this, with it 
> > > completely cranked up, is when the noise potentiometer is 
turned 
> up, 
> > > and the resonance and cutoff turned up. I can get a very faint 
> hissy 
> > > noise when I'm playing, and if I turn the resonance and cutoff 
> while 
> > > playing it changes the noise like you'd expect it to. Just 
almost 
> > > completely inaudible, this was all the way up and then fed into 
a 
> > > mixer with the gain all the way up.
> > This is good. It says the SSM2044 is not broken.
> > 
> > > I took the knobs off and backed the nuts off the pots, and took 
> the 
> > > CN16 connector off and measured pin 3, but I didn't seem to be 
> > > getting anything. Should I be measuring it from the wire 
harness 
> that 
> > > goes into it? That's where I measured it. I could be doing 
> something
> > > wrong. I did not check the CN2 pin 3, I was having difficulty 
> finding 
> > > it and had to quickly come up with an alternate solution for 
> > > performing this wednesday night. 
> > 
> > Basically I still think it is something not very troublesome; 
maybe 
> the 
> > low/mid/high-Levelswitch or the volume potentiometer is dirty or 
> (in 
> > worst case) broken. But both you could temporarily heal by 
bridging 
> them.
> > 
> > You may try to measure (or listen with an cable) to the following 
> > testpoints:
> > 
> 
http://fa.utfs.org/diy/korg_monopoly/mp_13_klm_353_layout_testpoints.j
> pg
> > 
> 
http://fa.utfs.org/diy/korg_monopoly/mp_14_klm_355_layout_testpoints.j
> pg
> > These show the pcbs from the solderside, so you don't have to 
> remove the 
> > pcbs from the front. The testpoints are marked yellow.
> > 
> > 
> > Florian
> >
>