Vox AD30VT power level knob

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>>1026469
A common problem and a legit solution, the carbon track (black ring in pic related) deteriorates or gets dusty, which means the wiper (silver thing, arrow related) makes intermittent contact, resulting in crackling.

Unless the potentiometer as had a real rough, dirty life, you may find it needs replacing anyway. Cheap pots do wear out over time. The cleaner will help short term but it might be time to start looking or a replacement.

The only risk of damage to the amp broadly would be a transient (reads, sudden pop or crackle) introducing enough signal to blow something further down the line. This is very unlikely in my experience though.

>>1026469
It is common problem with pots. An alternative to contact cleaner spray would be opening the pot for manual cleaning.
Either way, the results are usually good. You can also repeat cleaning, if the first try didn't work.

>>1026469
>and everything else
Also, don't. You just need to spray the inside of the pot. Find where its wires connect and blast in from that area, try to shoot some down the shaft as well. Run the pot back and forth from min to max a few times, hit it through the holes again to wash out the shit that just got cleaned off, give it 30 odd minutes to dry and you should be golden. May as well hit any other control pots while you're at it.

You do not need to hose down the entire innards of the amp if that's what you're getting at.

>>1026472
I wouldn't be trying to disassemble it, you'll never get it together as tightly as it was from factory, and that back will come back off eventually. If it is far enough gone that you need to take it apart, go but a new one for a few bucks.

>>1026471
Pardon my newness, but the potentiometer is what controls the wattage? The whole mechanism in its self I'm assuming? Do you think I should try to manualy open the pot like other anon suggested and manually clean it? And if so should I use switch spray?

I'm not gonna seriously tear it apart. Haha. I've had to unmount the chassis like six times already anyway due to their shitty factory input jacks falling in. I'm a skeptic if you hadn't noticed, mostly because I'm not super knowledgeable of the electricity aspect of the instrument. I live in a super small town so our 1 music shop is bound to charge me a ton just to ship it off for weeks and likely screw me.

>>1026476
Pardoned, and that's accurate. A potentiometer is a variable resistor. The can be used for anything from light dimmers on your wall to tone controls on the front of your amp to position sensors in remote control car servos. They operate by presenting a resistive load that varies depending on position ("turned all the way down" would be maximum resistance, "turned all the way up" would be minimum resistance). Think of them like a water tap. A tap varies the flow of water, a pot varies the flow of voltage. In this circumstance, they are used to adjust the output level of your amp (where watts = measure of output power). You could just as easily call it a volume control, after all, adjusting this pot changes your output power, hence the volume.

As I say, if I had a pot that was so far gone that it still sounded like shit after a clean, I would be looking for a replacement. You'll never get it back together as tightly as it was from the factory, which will allow dust and other junk in, and result in poor performance and eventual failure.

That's actually some perspective. What I here sounds like multiple lacking areas of contact throughout the rotation which is shit in between the track and wiper. I'll just get the cleaner and give it a good work over along with the other pots and inputs.

On a last note.... Is Deoxit d5 cool to use as far as you guys are concerned?

And in the event of utter defeat and depression, suggestions for replacement potentiometer?

Thanks for all the help and input fellas. Trying to become a man of action when it comes to repairs and upkeep of my gear, so it's cool to get advice from people who know what the hell they're doing. I'll check back in a little to see about the spray and plan b alternate potentiometer suggestions. Gotta get some shut eye while I can.

new pot = will work with 100% certainty, good for 10 years, less costly. requires soldering.

contact cleaner = will work with 75% certainty, good for a year maybe, costs more. no soldering.

to choose a pot, you need to know the resistance (like 10K) and the taper (either linear or logarithmic - the latter is used for volume pots). plus the mounting shaft should be same size or slightly thinner. if the shaft is very long, you may have to cut it, making sure the aluminum dust doesnt get inside the pot. one trick to doing that is to hold the head of the shaft in a vice. you dont hold the pot in the vice, obviously.

>>1026498
OP here again. Got my cleaner.one last question. Contact cleaner is NOT good to get on boards and shit right? The fucking potentiometer is in like the worst fucking spot ever to actually hit the pot. And after pulling out the chassis unit I've come to the conclusion that I should probably clean more than just the pots. I need to get a cover for this damn thing or something. Will post pics in a second if anyone cares or is even still around.

>>1026753
Contact cleaner is NOT good to get on boards and shit right?

Nah, it's good. As long as you let it dry completely before you fire it up you'll be fine.

> post pics
Do it, might not be as bad as you think

Cool. I used a little homemade air duster so it's already cleaner. I sucked it up and found a way to the pot. Hit it from there and from the actual peg slots on the outside. I took extra care to not leave puddles or anything. I used some q tips with the contact spray on it too to get the nooks and crannies.

>>1026476
You could look at a potentiometer as two adjustable resistors. It's only one circular resistive strip, but the movable wiper lug is a connection point between the other two.

In a guitar amp any time you see gain or volume, the pot is pretty much guaranteed to be used as a voltage divider.

Switchcraft jacks are really inexpensive online. The same goes for alpha pots.

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Shot of my tube and power pot.

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From the top

Well shit man... Sounds like it did the day I brought it home. Thanks for all the help. Hopefully this holds out for a while. My day has been made.

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>>1026812
Nice dude, glad to help.