2 Nov
2025
2 Nov
'25
11:53 a.m.
Try cleaning it as Paul saysand se if that works.
Carbon pots get a groove worn into them after time and the wiper ends up making
intermittent contact.
Usually you can take them apart and visually check.
It’s possible that just the wiper is worn.
Also possible the carbon element is cracked.
It all cases it’s just easier to replace the control.
Sent from my iPhone
On Nov 2, 2025, at 11:48, Paul Koning via cctalk
<cctalk(a)classiccmp.org> wrote:
On Nov 2, 2025, at 2:15 PM, Rob Jarratt via
cctalk <cctalk(a)classiccmp.org> wrote:
I have the contrast control on the monitor of my Olivetti M24 which has
become unreliable, you only need to touch it and the display will disappear
completely. It doesn't look too hard to replace the rotary potentiometer,
but I was wondering if there is any way to "repair" it to keep the original
part. It looks like this:
https://1drv.ms/i/c/fc758a5a91b91301/ESPGlbvW5wxGpXPC5kXfzVMBTUUW96GThzDMqZ_
i8jq7tA?e=Ehmo1T
I have a spray can of cleaner from Radio Shack that's designed to do this. I used it
a year or two ago to clean the pot on my toaster (the toast darkness control). The can
says it is "Tuner control cleaner & lubricant, part number 64-4315. The
ingredients list mentions 1,1,1,2-tetrafluoroethane, cyclomethicone, and mineral oil. I
suspect it's considered non-PC nowadays, but I'm keeping it.
It may be that turning the pot through its range a bunch of times will rub off crud.
paul