Rhodes Chroma Polaris

i just got another polaris off ebay---it supposedly had only a keyboard contact problem which i was going to fix...but apparently now that it arrived most of the controls are dead--- the LEDs go on but all the sliders dont have any effect...ALL sliders from volume to assignable. even the benders. I can change through all the programs (letters /numbers) and it seemed to go through auto tune- [6 blinks] ... but i cant modify the sounds. IT SEEMS THAT ONLY 3 BUTTONS DO WORK... noise, sine-square , and touch on/off for volume.
there had been a ribbin wire repair from left to right board on the lower connector ( using spliced in wire). but not the upper smaller ribbon.
i have tested for a simple continuity accross the repaired ribbon between the left and right board and it seems to be ok. any ideas which ribbon (i assume a ribbon wire) would be at fault to affect this odd array of controls. i have the service manual and schematics, but they dont show this type of info clearly to me (perhaps its in there somewhere?)

> From: wasteking1
>
> i just got another polaris off ebay---it supposedly had only a
> keyboard contact problem which i was going to fix...but
> apparently now that it arrived most of the controls are dead---
> the LEDs go on but all the sliders dont have any effect...ALL
> sliders from volume to assignable. even the benders. I can
> change through all the programs (letters /numbers) and it seemed
> to go through auto tune- [6 blinks] ... but i cant modify the
> sounds. IT SEEMS THAT ONLY 3 BUTTONS DO WORK... noise,
> sine-square , and touch on/off for volume.
> there had been a ribbin wire repair from left to right board on
> the lower connector ( using spliced in wire). but not the upper
> smaller ribbon.
> i have tested for a simple continuity accross the repaired ribbon
> between the left and right board and it seems to be ok. any ideas
> which ribbon (i assume a ribbon wire) would be at fault to
> affect this odd array of controls. i have the service manual and
> schematics, but they dont show this type of info clearly to me
> (perhaps its in there somewhere?)

If none of the analog controls work, then the problem is something in common
to all of them, which could be anything from the latch Z6 on the right panel
board, the connectors on the big ribbon cable between the panel and the main
board, or something in the A/D converter circuit on the main board. Since
all analog inputs are multiplexed onto one line, this is the sort of thing
that's difficult to diagnose without a scope, but easy to diagnose with one.

The first thing to do is to unplug and re-plug everything in sight, since
connectors can come loose, or even develop dirty contacts over time. The
only single thing that would affect both analog inputs and switches would be
the main ribbon between the main board and the panel. You may get lucky, and
that may fix it. If not, you'll probably need more than a multimeter to
figure it out.

--

Ciao, Paul D. DeRocco
Paul mailto:pderocco@...

--- In chromapolaris@yahoogroups.com, "Paul D. DeRocco" <pderocco@...> wrote:

>
> > From: wasteking1
> >
> > i just got another polaris off ebay---it supposedly had only a
> > keyboard contact problem which i was going to fix...but
> > apparently now that it arrived most of the controls are dead---
> > the LEDs go on but all the sliders dont have any effect...ALL
> > sliders from volume to assignable. even the benders. I can
> > change through all the programs (letters /numbers) and it seemed
> > to go through auto tune- [6 blinks] ... but i cant modify the
> > sounds. IT SEEMS THAT ONLY 3 BUTTONS DO WORK... noise,
> > sine-square , and touch on/off for volume.
> > there had been a ribbin wire repair from left to right board on
> > the lower connector ( using spliced in wire). but not the upper
> > smaller ribbon.
> > i have tested for a simple continuity accross the repaired ribbon
> > between the left and right board and it seems to be ok. any ideas
> > which ribbon (i assume a ribbon wire) would be at fault to
> > affect this odd array of controls. i have the service manual and
> > schematics, but they dont show this type of info clearly to me
> > (perhaps its in there somewhere?)
>
> If none of the analog controls work, then the problem is something in common
> to all of them, which could be anything from the latch Z6 on the right panel
> board, the connectors on the big ribbon cable between the panel and the main
> board, or something in the A/D converter circuit on the main board. Since
> all analog inputs are multiplexed onto one line, this is the sort of thing
> that's difficult to diagnose without a scope, but easy to diagnose with one.
>
> The first thing to do is to unplug and re-plug everything in sight, since
> connectors can come loose, or even develop dirty contacts over time. The
> only single thing that would affect both analog inputs and switches would be
> the main ribbon between the main board and the panel. You may get lucky, and
> that may fix it. If not, you'll probably need more than a multimeter to
> figure it out.
>
> --
>
> Ciao, Paul D. DeRocco
> Paul mailto:pderocco@...
>

thanks paul---it WAS a lose connector cable...the one labeled j-10.
it must have been jarred loose in shipment. now the controls work.

I was afraid it was those brittle mylar membrane ribbons which had been
repaired previously on this unit and didnt think of something way simpler. I
was suprised that those 3 buttons (noise,sine/square , and touch) were still
operative , that was what was confusing me . perhaps a couple pins still had
good contact. anyway --- you are the man.

'long live the polaris'