Rhodes Chroma Polaris

One pot, by the gold colored chip is a trim adjustment for the DAC.  
The polaris's CPU uses this to generate CV voltages that are clocked 
into the various sound generating parameters.  When the Polaris was 
designed, DACs were expensive so there is just one and that is 
shared.   The service manual describes calibrating this, and I've 
done it (I had a bad DAC and built a new one using modern parts) but 
you need a very good meter.   I doubt that is your problem. 

Another by the power supply (I think) pot is for the "power ok" set 
point.  You shouldn't need to touch that either unless you are having 
issues getting your keyboard to reset properly on power cycles.

As for the sliders, the service manual describes how to do a s/w 
calibration of the sliders.  You put it in this mode (I don't have 
service manual in front of me), and then just move the sliders 
through their range. 

However, it sounds like you have the common problem of 
damage/cracking on the aging ribbon wires that plug into the contol 
panel.  Carefully examine them, and if they are cracked they will 
need to be repaired.  On my polaris, I cut back to good material and 
used a meter to verify contact.

Also, the resonance control isn't 12bit analog like the others, it 
has only 8 positions (3 digital control lines).

-Ben


> --- In chromapolaris@yahoogroups.com, johnsound1@n... wrote:
> > Not sure what the pots are for, I do have the schematics and 
could 
> look when I get some time, but I wouldn't touch them if I were you. 
> > The Oscillator volume and other calibration/setup procedure is 
done 
> from the front panel, the steps are in the manual I believe, if you 
> have one. If not, I could forward them in a couple weeks.
> > Good luck w/your machine.  
> > 
> > 
> > 
> >