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Subject: Re: poly-800 mk1 seq speed slider broken

From: "p" <peteput@...>
Date: 2010-09-19

Ok so the track inside the pot has small "blank spots" towards the top and bottom, are these tracks actually on the pcb or the pot itself? i have been trying to find a 100k lin pot @45mm with a 35mm throw but so far nothing doing, do you know where i could find one?

poly love
pete.

--- In korgpolyex@yahoogroups.com, "p" <peteput@...> wrote:
>
> Hi. So i took her apart again, resoldered all the wires from KLM597-b. and no change again. took it apart once more and noticed inside the speed pot the contact seemed much more dirty than the bend rate and tune pots. so after a better clean with Servisol Super10 and a vigorous slider session things improved dramaticallly though not 100%, now after an hour or 2 things have gone back to norman slow and slower, should i take apart the pot and give it a thorough clean? is this possible without removing it from the board?.
>
>
> thanks so much for all your help...i'd be lost otherwise.
>
> pete.
>
> --- In korgpolyex@yahoogroups.com, "p" <peteput@> wrote:
> >
> > Hi Michael,
> >
> > thanks for the reply, i didnt see this until after i posted my last one...
> > one thing im not sure about is which settings on the multimeter to use and what the resistance values should be.
> >
> > pete.
> >
> >
> >
> > --- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@> wrote:
> > >
> > >
> > >
> > > Hi Pete,
> > >
> > > the problem is more likely NOT the actual clock circuit itself (found on the
> > > main board using half of IC36 and half of IC28 and sundry other discreet
> > > components). For details of that circuit see section "4" on the main circuit
> > > schematic in the files section.
> > >
> > > More likely is that there is a problem with the speed slider pot itself or the
> > > the connector CN2.
> > >
> > > The annoying part of this is that the service manual doesn't include an exact
> > > schematic diagram of the speed pot wired into the clock circuit.
> > >
> > > So you will need to do some tracing yourself. But I would start by checking that
> > >
> > > the slider pot runs through a range of resistance first. You will need a
> > > multimeter for that. If you don't have a multimeter then you will need to find
> > > someone that does or else go buy one.
> > >
> > > And then I would check to see that the three wires going from the main board to
> > > the display board via CN2 are not broken. Make sure all thee connections have
> > > continuity.
> > >
> > > Mike
> > >
> >
>