It went up in smoke. I changed Q1 and Q18. Checked the pin-out - and I'm sure i got it right. (Otherwise Q1 and Q18 would have been hot - and they weren't). Anyway - what happened when I plugged in the power was that KD4 (the small transformer in the -5V area) went up in smoke. And that's kinda odd..? So now I'm thinking of building a new powersupply for it. Since getting a new part for KD4 (I think it's called T1 on the board, but I'm not sure) will be kinda hard..? Any other suggestions? Cheers! //Jon --- In korgpolyex@yahoogroups.com, Marcus Wilson <JB@...> wrote: > > Q1 and Q3 can be replaced by: > BD140 > > http://www.dse.com.au/cgi-bin/dse.storefront/ > 4735dc390a33bb062740c0a87f9c06b4/Product/View/Z1444 > .85c ea > > Q18 can be replaced by: > BD139 > > http://www.dse.com.au/cgi-bin/dse.storefront/ > 4735dc390a33bb062740c0a87f9c06b4/Product/View/Z1443 > .85c ea > > just be sure to ensure they are in the right way around! > > I have had 3 polys with no powerup, and dirty looking transistors. > > By replacing these 3 transistors I have been able to resurrect 3 > polys so far! > > this secret is now out, and good luck to all who wish to try to > repair a dead poly using this replacement method. > > Once these are replaced you should be able to see 11 P on the display > of the poly, and re-load your patches. > > Best Regards, > > Marcus Wilson > > > > On 10/11/2007, at 10:35 PM, korgpolyex800 wrote: > > > Jon, > > > > I did a google search on "NTE185 replacement" and "NTE254 replacement" > > and got plenty of hits where you can get those transistors. > > > > Let us know how you progress. > > > > Mike. > > > > --- In korgpolyex@yahoogroups.com, "Jon" <shonokij@> wrote: > > > > > > Hi! > > > > > > New to the group and proud owner of a broken Poly 800 MKII! > > > > > > The guy who owned it before me tried to restore it, with poor > > results (I think his plan was to > > > cover it with solder and pray it works afterwards.. it didn't!). > > > > > > I've cleaned his mess up. But I'm missing Q1 and Q18 looks kinda > > abused. > > > > > > Since Q1 - B744 is no longer in production. It's replaced by NTE185 > > - hard to get for me and > > > expensive. And it's the same with Q18 - B794 replaced by NTE254. > > > > > > So I was wondering if you guys have any suggestions for other parts > > i could exchange Q18 > > > and Q1 with? > > > > > > Thanks! > > > > > > //Jon > > > > > > > > > >
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Re: where to find parts to replace Q1 and Q18? bringing dead polys back to life!
2007-11-20 by Jon
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