A novice's questions about scratchy volume controls

Scratchy normally means worn , if a standard pot (usually isn't) then replace. If not standard, then dismantle an "recondition", details on one of my tips files off URL below. Squirting anything is usually pointless .

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

~db~® wrote in news: snipped-for-privacy@4ax.com:

Depends on what's causing the "scratchy" behavior.

It can be as simple as a speck of dust on the resistive element, so each time the wiper goes over it, there's an abrupt change in resistance. In that case, you can sometimes cure the problem by turning the knob back and forth many times to sweep the speck of dust off the element (or grind it down to dust).

Another case is a very cheap resistive element which has a rough surface. Replace it. A proper resistive element, after extensive use, may develop a rough surface. Replace it.

Of course, if the volume control is specialized, you might have a hard time finding a replacement. An internet store such as

Can you get at the part of the volume control that has three terminals, or only from the front of the radio/tv set/whatever/ It is almost impossible to do anything from the front. If you can get to the back of the control where the three terminals are located, you can spray tuner lubricant into the control throught the spaces where the terminals go into the control. I have also sprayed naptha into controls. After spraying, with the device UNPLUGGED, rotate the control back and forth several times. Then allow the lubricant to dry, at least 15 minutes, maybe more, and then use the device. The lubricant will help loosen dirt that may be on the track, It may not help, but it should not make things any worse. I have also sprayed a little WD-40 when nothing else was available, it helpd noticeably.

H=2E R. (Bob) Hofmann

If I tried replacing every switch or volume control I came across, I would spend most of my time doing that. Alcohol is probably most common cleaner and works well. A lubricant after cleaning often helps or is necessary. There are not many lubricants made for volume controls. CRC 2-26 is not a bad product. I used a product once that was made in the 60's, was a white grease spray for controls. The pure red form of deoxit wold probably be very good, and there is a blue lubricant from Caig made especially for controls.

greg

"hr(bob) snipped-for-privacy@att.net" wrote in news: snipped-for-privacy@l77g2000hsb.googlegroups.com:

Yikes!

I have used Servisol Super 10 aerosol switch cleaner / lubricant for many years, and the genuinely dirty pot that this excellent product cannot recover, is rare indeed. As others have said though, mechanical wear on the track is a different matter, and control replacement is usually the only long-term solution.

Arfa

Go to Radio Shack if you are in the US and buy Deoxit...spray a shot in the pot and turn it lock to lock about 10-20 times and try it again...Deoxit Gold is not for pots... see website for details...J.P.

J.P. wrote in news: snipped-for-privacy@4ax.com:

wrap a wire or string around the pot's knob and use that to see-saw the pot lock-to-lock;you can do it much faster and easier.

lawl mang i ned help fo my projet i alredy posted biout i really ned to no ;___;

is

Thanks, everyone ... in this case, deoxit did the trick. And this is a good thing since the volume control is integral to the on-off switch -- or vice versa. ~db~®

If you get DC through any of these things you get a scratchy volume control. Check for screwed electro.

Another way to clean the pot, but not a long term solution is turn off the set and turn the pot from end to end lots of times, it moves the dirt about on the track.