I only know basic electronics (Transistor, resistor, diode ,...) So the 'baby-talk' is ok :) Thank you all so much for the quick input so far. :)
There was no beep when testing the Diode.
I'll try the 9V test, and the 2SB744 right now... After I figure out the schematics.
:)
Thank you all for the help so far!
--- In korgpolyex@yahoogroups.com, Martin Ator <cyllall@...> wrote:
>
> OK.Not sure what those readings are. You could try to apply power and see if you can find the 9v after the power socket. Is there a continuity tester on your multimeter? i,e is there a way you can make it beep if there is a short circuit? Some settings depending on the meter, will make a beep if you touch the meter's leads together, so if two parts of a circuit are joined you can trace it easily. First find the negative of the power socket, and then use the positive meter lead to check each side of the diode. If you find the 9v, follow the circuit until it disappears. Sorry if you think that I'm talking to you like a baby, I don't know how much experience you have. You can also identify an IC from the circuit diagram and test if power is getting to it. This might be easier. Try IC24 80C85. Pin 20 is negative/VSS and Pin 40 is Positive/VDD
>
> There is a link to some schematics earlier in this message. These ones by Mr Pearce are probably the clearest images around.See if you can find the parts you are checking in real life,here.
>
> Don't forget the 2SB744
>
>
>
>
> ________________________________
> From: kjelle.vergauwe <bobsrampenbedrijf@...>
> To: korgpolyex@yahoogroups.com
> Sent: Sunday, 29 July 2012, 10:32
> Subject: [korgpolyex] Re: Poly 800 MK 1 Short circuit
>
>
> Â
> I'm not really good with a multimeter, but....
> Just tested the Diode. I'm measuring 587 and 1. No beep though.
>
> Also noticed when measuring that the wires from the diode are black, I could scrape black dust off of it. (see picture)
>
> http://dl.dropbox.com/u/7760238/poly%20800/Diode.JPG
>
> --- In korgpolyex@yahoogroups.com, Gordon JC Pearce <gordon@> wrote:
> >
> > On 28/07/12 18:33, Martin Ator wrote:
> > >
> > >
> > >
> > > If there is no pop and nothing on the display, or any other noises, then
> > > probably power isn't getting into the circuits. Any of the parts
> > > designed to protect against short circuit in the power circuit could be
> > > dead. The diode I told you about is a good candidate to start looking
> > > from. I have had to replace one in the past. If you have a diode test
> > > you can check this or just see if 9v is getting to the other side of the
> > > diode.
> > > I think it is the same as a 1N4004 diode.
> >
> > http://www.oldcrows.net/~patchell/poly800/poly800.html
> >
> > Check the 2SB744 "pre-regulator" regulator, which is in the negative
> > lead from the power socket.
> >
> > D2 is just to protect against incorrect polarity.
> >
> > --
> > Gordonjcp MM0YEQ
> >
>