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Prophet 08 Potentiometer problem

Prophet 08 Potentiometer problem
« on: October 17, 2018, 02:05:18 AM »

I have a Prophet 08 converted to PE.
After changing it over everything was working just fine for a certain time.
I didn't touch the synthesizer for several months and now I discovered that one of the potentiometers does not work as it should. At first, it jumped from 1 to 127 without intermediate values. After calibration, it reaches only the value of 20 jumping to 127 at the end of the scale.
I tried air duster, was changing PotMode settings - all without much effect.

In addition the value of the parameter starts to "tremble" closer to the end of the scale.

I've searched this forum for a similar issue, but didn't find an example describing exactly my case.
Do I need to replace the potentiometer somehow or is it possible to repair it?

Re: Prophet 08 Potentiometer problem
« Reply #1 on: October 17, 2018, 06:52:24 AM »
As a last possibility, you could try cleaning the potentiometer housing with deoxit.  That was the old solution around here, but it was usually only a temporary fix.  Otherwise, you may have a faulty individual potentiometer, rather than a software issue.  Contact DSI:

Phone: (415) 830-6393 x1
Fax (707) 286-5501

Re: Prophet 08 Potentiometer problem
« Reply #2 on: October 18, 2018, 03:48:18 AM »
To me, it also looked like faulty pot, but part of me just didn't want to believe it.
So I was (still) trying to do as much as possible before things will come to disassembling the synth and soldering.

Thank you for your answer.

Re: Prophet 08 Potentiometer problem
« Reply #3 on: October 18, 2018, 05:52:40 AM »
Your welcome.  The folks at Sequential will take good care of you.