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The "pots" issue

The "pots" issue
« on: December 27, 2016, 04:52:18 PM »
I've had a PEK now for about 2 years and love it, but lately have noticed values jumping around when I turn some of the controls. After further investigation I find that I have the early version with the  sketchy pots for which you can get the PE upgrade kit (currently out of stock at DSI).

I found on You Tube a video that showed fixing this problem with a high quality contact cleaner which seemed to work.

Question: is this the typical issue with those older pots and is cleaning them an OK, if temporary, solution? For some reason I thought this pot issue was something to do with relative vs absolute data reads where the value would jump to the new value when you selected a new sound (with the old pots) and the newer pots didn't do that.

I don't mind cleaning the pots every year or so if I can save a few hundred dollars!

Re: The "pots" issue
« Reply #1 on: December 27, 2016, 05:28:59 PM »
The endless encoders can develop all types of annoying behaviors, from taking large leaps with just a touch to hardly changing no matter how you turn the parameter.  I had the problem with two Prophet '08's.  Cleaning the housings with deoxit is fairly easy (it took about 30 minutes) and solves the problem for at least several months at a time.  I'd say you could get by if you did it once or twice a year. 
« Last Edit: February 01, 2017, 05:56:15 AM by Sacred Synthesis »

Re: The "pots" issue
« Reply #2 on: January 31, 2017, 09:59:59 PM »
I bought one of the early models and had this issue quickly! Ended up selling the keyboard at first opportunity.

Re: The "pots" issue
« Reply #3 on: February 01, 2017, 06:55:05 AM »
Yeah, I would never live with the erratic endless encoders problem.  Either sell the instrument with a full disclaimer to the buyer, or pay for the upgrade.

Re: The "pots" issue
« Reply #4 on: February 01, 2017, 09:01:18 AM »

I had this problem fairly soon after I got my PEK.  The Deoxit (Radio Shack used to sell it) worked well for the PO8.  I treat mine every year for the knobs that need it.   For the PEK I have had somewhat less success.  It was my oscillator shape knobs were especially screwy acting.   So I applied the deoxit treatment an noticed some effect of success, but the "jumping" started to reoccur a few months later.  It looks to me that the open port on the side of the little encoders is smaller on PEK and it's harder to get the fluid into the part.    I eventually wrote to DSI who sent me two free encoders to replace my bad actors.   It requires soldering, which I can do somewhat, but not extremely well.  Anyway,  I managed and while not pretty at all, I was able to replace that encoder.

Keep in mind in the meantime that you can just use the master soft knob by the display for any parameter you are currently adjusting (provided that isn't jumping too).
DSI Equipment: Poly Evolver Keyboard, Evolver desktop, Prophet 8,  Pro-2, OB6, P-12

Re: The "pots" issue
« Reply #5 on: February 21, 2017, 02:30:45 AM »
I bought an MEK last year that had the issue and contacted DSI who provided replacement boards for the cost of shipping as some models have a known fault - definitely worth looking into, they were really helpful about it and didn't care that I wasn't the original owner.