Hi Marcus, I thought that since the +5V part was working perfectly I'd leave them out.. But i figure it wouldn't hurt to change them anyway. Thanks for the quick reply! Cheers! //Jon --- In korgpolyex@yahoogroups.com, Marcus Wilson <JB@...> wrote: > > Hi Jon > > in my earlier email, I suggest to replace Q1 and Q3 also > > ensure they are the right way around, and see if that helps > > I also gave part numbers for those > > best regards, > > Marcus Wilson > > On 13/01/2008, at 8:19 PM, Jon wrote: > > > Hi! > > > > I just got myself another broken Poly-800. (The first one I got is > > now beyond repair. As I was > > offered a second one. I thought: Two minus makes a plus..). But > > now, after picking the new > > one appart. It seems like the -5V circuit is broken. I've replaced > > Q18. But the only reading i > > get is +0.9V where it should be -5V. > > > > Could it be that small transformer that's busted? (KD-4? xD-4? It's > > hard to read the name on > > the schematics. And it says T1 on the circuitboard). The output of > > it is +0.45V (Measured at > > leg 1 of D10), I asume it shoudl be -2.50V instead? > > > > Any ideas on how to replace it? > > > > The long way, I guess, is to replace the entire circuit with a AC- > > DC converter that takes 9VAC > > in and with a 7805 and a 7905 regulates it.. But it seems like to > > much trouble right now.. Or? > > > > Thanks! > > > > //Jon > > > > > > >
Message
Re: Not getting -5V?
2008-01-14 by Jon
Attachments
- No local attachments were found for this message.