Scratchy, Non-Uniform Old Volume Control

[Avogadro33]

Scratchy, Non-Uniform Old Volume Control

We just restored a Fisher 800 (TA-800) receiver. One remaining problem: the volume control exhibits areas of scratchiness and non-linearity.

I am aware that there is a spray product called “DEOXIT”, mentioned in these forums. However, I also read a message from someone who stated that Deoxit must NEVER be used on a volume potentiometer (maybe tone control pots as well). Deoxit is for switches and other metal contact points only, such as tube pins. On a volume pot, instead use a product called “FADERLUBE”. However, in other posts the recommendation for the volume pot was to FIRST use Deoxit, THEN use Faderlube. So we see that there is a conflict in the recommendations.

I have not (yet) ever used either. Can someone provide a brief rundown: which, when and why?

Thank you.

 

[larryderouin]

DeOxit (D-5 or D100) is the cleaner. Not to be used on "SLIDER controls" as it has minimal to NO lubrication. You CAN use for Rotary Switches and Rotary POTS!
Faderlube (F-5) is more lubricant than cleaner (it still has a little cleaner). It was designed for SLIDERS, but is used AFTER D-5/D100 to replace lubricant washed away by D-5/D-100.
Shield (S5 / S100) is a long term protectant with lubricant properties.

Give the Volume pot a shot of D-5. turn it a couple times to enhance operation. (It works best with time and friction, by scrubbing off environmental crud, then allowing it to be flushed out). After an hour or so, give it a short shot and exercise the pot from lock to lock 30-40 times. Now give it a shot of Faderlube. Let sit overnight so the carrier will dry off and evaporate. Test. Rinse and repeat if necessary.

 

[Avogadro33]

Thank you, Larry. Your instructions are very clear.