Crackle/static Bursts

[Electric Mulch]

I just completed my first wiring job on a PBass knockoff.

My soldering skills were a bit out of touch but I did a better job than I expected, but I'm unsure if I got everything quite right. I think my grounding is wrongish.

When I adjust the volume pot I get a static burst/crackle. If I maintain contact with a string, there's a bit of a buzz.

Any suggestions?

[Akula]

Sounds like the pot's dirty. You can get cleaning products for them, but if it was a cheap pot, its probably better to just replace it

As for the buzz, it goes away if you take your hands off the strings? Maybe your output jack's wired up back to front...

[Samba Pa Ti]

i use wd40 to clean pots, sprayed in the little hole on the casing and then i turn the wiper from 100% to 0% a few times and spray a bit more and repeat till its all nice and slick.

[Paul Marossy]

Do you have active pickups? It sounds like you might have DC (direct current) on the pot somehow and/or a bad connection to ground. Look for a "cold solder joint" on your volume control connection to ground.

Edited April 19, 2010 by Paul Marossy

[Electric Mulch]

Sounds like the pot's dirty. You can get cleaning products for them, but if it was a cheap pot, its probably better to just replace it

That should be the Allparts Pot. The Tone's a Fender branded. Ended up at two shops since one only had a 250 and the other a 500. I might have that flippflopped.

As for the buzz, it goes away if you take your hands off the strings? Maybe your output jack's wired up back to front...

Yes, it does.

I may give that a try.

[Electric Mulch]

Do you have active pickups? It sounds like you might have DC (direct current) on the pot somehow and/or a bad connection to ground. Look for a "cold solder joint" on your volume control connection to ground.

No, it is a passive system.

[Paul Marossy]

If you had the pots switched around, it wouldn't cause that problem. It's either a grounding problem or maybe due to reversed wires on your output jack.

Or possibly a defective pot. That's rare, but it can happen.

[ShadesOfGrey]

I had something similar yesterday when I installed two new humbuckers in my mockingbird knockoff.

No output except for static / hum when I touched anything ground related, like the knobs or the jackplate.

Found out my hot-wire was broken off from the jack, with the ground-wire still remaining.

But yeah, seems it's ground related. If the ground didnt fit somewhere in the equation, touching the strings shouldt result in static.

So my guess is that the ground wiring 'bleeds' into the hot somewhere. The volume pot seems a good start to look, but might just be a sepperate issue with a dirty pot.

Check that you have no broken wires, spilled bits of solder, bad joins or exposed wire touching things they shouldnt.

If you cant find the problem, try elimination of the problem by rewiring it without the volume pot to see if the problem persists. If so, just replace that.

EDIT:

If you had the pots switched around, it wouldn't cause that problem. It's either a grounding problem or maybe due to reversed wires on your output jack.

I hadnt thought about that. That could actualy be the cause.

[Electric Mulch]

Went to add some pictures as I finally had a chance to get the pickguard off today and every single one was a little blurry or bright from the flash. So. No pictures. Aside from the general body shot of the bass.

Bought a new input/output jack - that was the only piece I recycled from before, redid the ground soldering on the tone pot, switched out the cap for another one, and used a different solder ( 63/37 instead of 96/4 ) and put it all back together again. Not a bit of buzz or hum unless I put my hand right on the pickups - which I understand should happen.

I didn't reverse the wiring on the jack, so I'm guessing it was that crap soldering job on the tone pot - it had broken loose.

[Paul Marossy]

Cool, glad you got it fixed.