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Subject: Re: Schema for 12/24 dB filter cutoff slope mod: new file (JPG) and photo uploaded

From: "AARON" <aaron3900@...>
Date: 2012-11-12

Hi Mike,

Yes, I noticed that it was non-polarized when I was taking it out last night.

I assume that Dave came to that conclusion that it's a polarized cap because the PCB has a "+" where one of the leads solders into the board. But from the standpoint of wiring up the 12/24dB mod, the distinction is important, I think, because if you take the other lead -- the "negative" one -- and wire that one up to the switch, it won't work. So I guess he means simply that the lead that's stuck into the hole marked "+" is the one to use.

By the way, I replaced C103 with a polarized cap last night (soldering the positive lead into the hole marked "+" on the board), and everything's working fine. I guesss whether you use a polarized or non-polarized cap really isn't critical here.

Aaron

--- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@...> wrote:
>
> C103 is a non polarised electrolytic cap. It is not polarised and does not have a + or - pin. I am not sure how Dave came to the conclusion that the cap has a positive and negative side. But it doesn't.
>
> Mike
>
>
>
> ________________________________
> From: AARON <aaron3900@...>
> To: korgpolyex@yahoogroups.com
> Sent: Monday, November 12, 2012 2:25 PM
> Subject: [korgpolyex] Re: Schema for 12/24 dB filter cutoff slope mod: new file (JPG) and photo uploaded
>
>
>  
> Hi all,
>
> I'm a new member here, but certainly not new to the Poly 800 (I own two) or modding (I've done the Moogslayer mod on one of my machines).
>
> I'm glad I found this particular thread. Before I became a member today, I found a 2003 thread regarding this mod by doing a Google search. It said to use the NEGATIVE lead of C103.
>
> So last night, I excitedly got to work on the mod, wired it up exactly as instructed and got ... well, a big bunch of nothing. No sound at all. So, I had to replace C103 with a new 10uF cap (since I'd already cut the negative lead loose from the board), and the synth now works again.
>
> Tonight, I'll try 'er again with the revised instructions. I may just replace C103 with a 10uF axial-lead capacitor (soldering in just the negative lead, of course) to make the job a bit easier. I'm eager to hear how this mod sounds!
>
> Cheers to Dave for sharing the revised info (in 2007).
>
> Aaron
>
> --- In korgpolyex@yahoogroups.com, "Dave Bowman" <davidmochen@> wrote:
> >
> > Hi all,
> >
> > Having been requested by a member of this NG to provide some details
> > about the 12/24 mod (which of course I didn't happen to create, but
> > nevertheless managed to implement succesfully), I just uploaded a jpg
> > file to the Files section and a photo to the Photos section in my
> > album (Dave's Poly 800).
> >
> > I hope this may be of help, since the mod's description featured in
> > an older post, though useful, unfortunately has a mistake as regards
> > the C103 capacitor's polarity.
> >
> > I performed the mod exactly as is described in the pic/file, and it
> > works fine.
> >
> > Sorry for the spellcheck lines under the words... I created the
> > schematic using Microsoft Word and forgot to turn the autospell
> > feature off... it's late here in Argentina and I should collapse in
> > bed right now!
> >
> > Cheers,
> >
> > Dave
> >
>