Re: [chromapolaris] Digest Number 779
2017-06-26 by John Leimseider
I have many of the type 2 slide pots for the polaris. They need a little modding to fit the earlier panel boards but they last forever. They were used on the later panel boards, I assume because of the high rate of failure of the first type.
John Leimseider
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On Jun 25, 2017, at 7:21 PM, "chromapolaris@yahoogroups.com" <chromapolaris@yahoogroups.com> wrote:
6 MessagesDigest #7791aRe: Changing to 240v by synthparts2aFaulty Envelope Depth by conorstrachan2bRe: Faulty Envelope Depth by "Paul D. DeRocco" pderocco02cRe: Faulty Envelope Depth by conorstrachan2dRe: Faulty Envelope Depth by wjmwpg2eRe: Faulty Envelope Depth by "Paul D. DeRocco" pderocco0MessagesSat Jun 24, 2017 9:22 pm (PDT) . Posted by: synthpartsSun Jun 25, 2017 2:42 pm (PDT) . Posted by: conorstrachanI seem to have an issue with the envelope depth slider. It is not responsive. The only one on the keyboard that is. However it is working through the editor in midi quest so it works so this seems like a mechanical problem or something on the panel board(it hasn't new panels). Does this sound like it needs a new potentiometer?
Thanks
ConorSun Jun 25, 2017 3:46 pm (PDT) . Posted by: "Paul D. DeRocco" pderocco0> From: conorstrachan@...
>
> I seem to have an issue with the envelope depth slider. It is
> not responsive. The only one on the keyboard that is. However
> it is working through the editor in midi quest so it works so
> this seems like a mechanical problem or something on the
> panel board(it hasn't new panels). Does this sound like it
> needs a new potentiometer?
Most likely the wiper or elements are dirty, or the wiper contacts are bent. If you remove the slider from the board, you can pry back the tabs that hold it together, then clean the inside with alcohol and a Q-tip. If it appears the wiper contacts are bent, you you should be able to bend them back with sharp tweezers if you're very careful. If the contacts are broken, then you're SOL and will have to find a new slider. I've repaired quite a few sliders this way.
--
Ciao, Paul D. DeRocco
Paul mailto:pderocco@...
Sun Jun 25, 2017 4:04 pm (PDT) . Posted by: conorstrachanThanks Paul
It got the board off and it appears that the slider does not have very much resistance compared to the rest. I guess as it's unresponsive it must be disconnected on its contact that's why it feels loose on the track. Would bending the pins sort this out? Might have to be looking at finding a new sliderSun Jun 25, 2017 4:08 pm (PDT) . Posted by: wjmwpgFor what it's worth I have had great results opening up the Polaris sliders, giving them a decent cleaning, and re-bending the contacts back to where they should be ... and then closing them back up again. Personally I have found the easiest way to bend the bottom clips open is to use a small set of wirecutters and to get the edge of one blade positioned under the clip and then just gently pry it up.
Sent from my iPhone
Sun Jun 25, 2017 4:19 pm (PDT) . Posted by: "Paul D. DeRocco" pderocco0> From: conorstrachan@...
>
> It got the board off and it appears that the slider does not
> have very much resistance compared to the rest. I guess as
> it's unresponsive it must be disconnected on its contact
> that's why it feels loose on the track. Would bending the
> pins sort this out? Might have to be looking at finding a new slider
If by "pins" you mean the things attaching it to the circuit board, then no. It sounds like the wiper contacts on the movable shaft assembly, which bridge between the resistive track and a parallel conductive track, are bent so they are no longer touching the tracks, or possibly broken. As James and I said, these things can be taken apart to clean them and unbend the wiper contacts.
--
Ciao, Paul D. DeRocco
Paul mailto:pderocco@...