Here are some photos taken before and after cleaning the Alps 100K ohm pots used on Phase Linear 400 series II, 700B's, 700 series II, and Dual/D-500 series II amplifiers.
These days, I always dis-assemble the pots and clean the carbon track, annular ring and wiper arms. I then apply a layer of lubricant (i.e. LPS1 or De-Oxit) to the carbon track and annular ring. And of course it gets re-assembled then after.
Most people just shoot a bunch of spray inside the open end of the potentiometer hoping to dis-lodge any loose carbon particles, etc.. In this process the "pot goo" which Phase Linear had placed in the back end of the potentiometer will be thinned out and that silkier smooth feel will go away and that Alps pot will feel like that cheap pot it was in the first place.
NOTE: I do recognize that over the years that in some potentiometers the "pot goo" has been drying out and the amount of torque required to turn the pot shaft has increased.
Albeit, there are pros and cons to sealed pots (i.e. the more expensive Allen Bradley, Centralab, Clarostat, etc.) versus the open back sealed pots (i.e. Alps). Eventually the carbon track will wear and break down into loose particles. In which case there isn't much you can do to the sealed pots since they don't easily disassemble. At least with the cheaper Alps pots that Phase Linear used you can service them.
Ed
These days, I always dis-assemble the pots and clean the carbon track, annular ring and wiper arms. I then apply a layer of lubricant (i.e. LPS1 or De-Oxit) to the carbon track and annular ring. And of course it gets re-assembled then after.
Most people just shoot a bunch of spray inside the open end of the potentiometer hoping to dis-lodge any loose carbon particles, etc.. In this process the "pot goo" which Phase Linear had placed in the back end of the potentiometer will be thinned out and that silkier smooth feel will go away and that Alps pot will feel like that cheap pot it was in the first place.
NOTE: I do recognize that over the years that in some potentiometers the "pot goo" has been drying out and the amount of torque required to turn the pot shaft has increased.
Albeit, there are pros and cons to sealed pots (i.e. the more expensive Allen Bradley, Centralab, Clarostat, etc.) versus the open back sealed pots (i.e. Alps). Eventually the carbon track will wear and break down into loose particles. In which case there isn't much you can do to the sealed pots since they don't easily disassemble. At least with the cheaper Alps pots that Phase Linear used you can service them.
Ed
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