Crackle & pop - Fixing and old Amp

[dreamspy]

Hi there

I hope that this forum is not to HighTech for my question

But I have a coulple of old amplifiers, and I think that the buttons are starting to loose contact. I get allot of crackles when I press/turn buttons, and sometimes the sound gets distorted, but goes back to normal if I turn the knobs a little.

Can anyone recommend some good way of fixing this issue? This is probably just some standard maintenance thing, but I'we never done this so I'd like to hear your opinions.

I was thinking about just removing the buttons and front plate.
Blowing all dust away with an aircan.
Clean the electronics with alcohol.
Let them sit and dry.
Go to the electronic store and get some "contact spray" (if that's what it's called), and spray that on the electronic part of the buttons.

How does that sound? Am I on the right track?

regards
Frímann

[nigelwright7557]

Either use a contact cleaner spray or replace the offending components.

Personally I would replace them.

[dreamspy]

Originally Posted by nigelwright7557

Either use a contact cleaner spray or replace the offending components.

Personally I would replace them.

Replace them, really? It's about every other button.

I'm curious though, it's not that hard to replace them? I'm quite handy with the soldering iron, but I'we never actually thought about replacing the buttons.

[sumaudioguy]

Tech Spray "blue stuff" is the best choice for switches but do not use on level controls. For level controls use Caig MCL.

[Spiny]

On old kit its usually difficult to get switches that fit but Switch cleaner will get them working most of the time,

Volume and tone controls are a different problem, these are the rotary controls and whilst sometimes switch cleaner sprayed into them will cure the crackles. I find that sometimes the resistive tracks are pitted where the pot has been left in one position for decades....

In these cases replacement is the only cure. The value of the potentiometer should be stamped or printed on the case of the control and suitable replacements can be found from the usual suspects (Mouser CPC Farnell Digikey etc.)