Unlike automobiles, most solid-state electronics—receivers, amps, and preamps—function beautifully for years with little or no attention. But sooner or later, you may notice some of the controls on your receiver or preamp will become noisy or "staticy" when you rotate them. The volume control is the big culprit but it’s common enough for balance and tone controls to get noisy as well. Selector switches or pushbuttons may become intermittent from time to time. This condition may show up in as few as two or three years and it’s commonplace in components that are five years old. After 10 years or more, it’s unusual to find any electronic device with controls that are free of noise or static.
It’s mostly a result of oxidation of the internal metal moving parts within the potentiometer or switch, but dust certainly gums things up as well. You needn’t think these parts are wearing out. They’re not. They just need cleaning and de-oxidizing. And what better time than the advent of Spring to clean those controls? There are special sprays intended for exactly these chores. The contact cleaners I’ve found effective include ProGold GxL and Cramolin Special Spray, both from Caig Laboratories (www.caig.com), and Stabilant 22. Another similar product is Tweak. I’ve tried RadioShack’s TV Tuner and Control Cleaner, but I’ve found its cleaning effect is very short-lived, whereas the other cleaners will keep controls noise-free for years before you have to do them again.
The trick is to get at the noisy control. You have to disconnect your receiver or preamp and remove the bottom plate and perhaps the metal enclosure. These sprays come with a tiny tube that let you insert the end in any opening in the offending control. A quick spritz is sufficient. Do it while you rotate the control back and forth. Some selector switches may have a mechanical link from the front panel to an actual switch mechanism elsewhere inside the preamp or receiver. Just follow the link and spray briefly into the mechanism while you operate the switch. That’s it.