Hi Pat.
No didn't get to the bottom of it, but it wasn't any of the following...
Filter chip, electrolytics, filter caps, control inputs (multiplexers), VCA
transistors (just incas it was a loading issue).
The only thing I did that seemed to make difference was to clean the board
with isopropyl. The effect of doing this was that once the Polysix
has warmed up.... The problem disappears.
I can only think that the issue is related to either spillage, or
electrolyte on the board in that area.
If you have any joy, please let me know.
Cheers
B
No didn't get to the bottom of it, but it wasn't any of the following...
Filter chip, electrolytics, filter caps, control inputs (multiplexers), VCA
transistors (just incas it was a loading issue).
The only thing I did that seemed to make difference was to clean the board
with isopropyl. The effect of doing this was that once the Polysix
has warmed up.... The problem disappears.
I can only think that the issue is related to either spillage, or
electrolyte on the board in that area.
If you have any joy, please let me know.
Cheers
B
On Wednesday, July 31, 2013, murger wrote:
> **
>
>
> Hi Bob,
>
> Any luck with this one? Got the same issue. Looking at the 560p between
> pin 4 and 5 of the ssm.
>
> Pat
>
> --- In PolySix@yahoogroups.com <javascript:_e({}, 'cvml',
> 'PolySix%40yahoogroups.com');>, Robert Stewart <bob@...> wrote:
> >
> > First thing I did.
> > Problem is not the SSM2044
> >
> > :-s
> > On 10/07/2013 14:53, alesisfusion8hd wrote:
> > >
> > > Have you swap SSM2044 with another voice to make sure the issue
> > > follows the filter? Never serviced a Polysix though, but I had a
> > > similar behavior on my Trident MkII. The SSM2044 was faulty.
> > >
> > > HTH
> > > Fran�ois
> > >
> > > --- In PolySix@yahoogroups.com <javascript:_e({}, 'cvml',
> 'PolySix%40yahoogroups.com');> <mailto:PolySix%40yahoogroups.com<javascript:_e({}, 'cvml', 'PolySix%2540yahoogroups.com');>>,
>
> > > "blzproductions" <bob@> wrote:
> > > >
> > > > Hi
> > > >
> > > > Servicing a Polysix for a client, and have come up against a weird
> > > issue, which I can't fathom. Hoping someone out there has had a
> > > similar issue, and may be able to help...
> > > >
> > > > One voice has a faulty filter section in that the resonance can be
> > > adjusted as per the line up procedure, but then if you lower the cut
> > > off, the resonance decreases.
> > > >
> > > > I have ruled out the problem being the SSM2044, all signals coming
> > > into the chip (ie. cut off/resonance control etc.) look correct, and
> > > are comparable, and I'm pretty sure it's not the filter caps as
> > > they're not electrolytics or Tantalums.
> > > > Also the connections between the caps and the filter chip are all OK.
> > > >
> > > > If anyone has any ideas, please get it touch. It's beginning to
> > > drive me mad.
> > > >
> > > >
> > > > Bob
> > > >
> > >
> > >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
[Non-text portions of this message have been removed]