500k Pot going crazy

swampblues

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put a new set of CTS 500k 10% in my les Paul and the Bridge volume has gone nuts. Worked fins for a few days then the craziness came about. When the volume pot is rolled back to about 2 everything is fine, the volume drops as it should but any lower than that there is a funny sound and volume jumps back to full volume. Thought it may be a cold or bad solder joint so I redid all the solder to this pot. No help, doing the same thing. Bad pot possibly even though they are brand new? This are the spec’s from Art of Tone
500K Ohms/5% Tolerance (485K-535K)
Audio Taper
Bakelite base plate
Solid brass c-clip reinforced shaft
Solid brass bushing
3/8-32 US thread
3/8" (short shaft) bushing height
Split, fine 24-tooth, knurled, .236” diameter shaft
Chamfered shaft for easier knob installation and removal
Each pot comes with hardware - nut, dress washer and lock washer
Requires 3/8" diameter mounting hole
Pot is manufactured and branded by CTS specifically for The Art Of Tone (TAOT), Part # 450S500K TAOT.
 

DarrellV

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Simple...

Do you have an ohmmeter?

Unsolder the leads from it, you don't have to remove it.

Touch your ohmmeter leads to the center and the non grounded lug.

Set the pot to full on (zero ohms)

Rotate the control...

Note the value as it climbs toward 500K

Near the end does it drop to something lower and closer to zero ohms?

Its shot...

New doesn't mean too much anymore... these are machine mass produced no matter how fancy the name sounds.. sometimes things get by.

Look at Gibson QC!

Maybe warranty?
 

cooljuk

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The first thing many assume is a factory bad pot or pot damage by overheating.

Those are almost never the case.

It's almost always a soldering/wiring error.


I've been buying CTS pots in the thousands and testing/sorting each one for approaching a decade now. I know they are Asian-made and I wish there was a US equivalent I could use, but I have to hand it to CTS. The only factory-bad ones I've ever found were a few that arrived with a leg broken off and a few that were out of stated tolerance (but still worked fine, and I actually find these desirable for voicing some guitars). I have yet to receive a single one that just didn't work.


Pots can be damaged by overheating, but one has to really try hard to do that. They are a pretty tough electrical component. If you only have your iron on the pot for a few seconds, you won't damage it. If you need more than a few seconds to solder anything, you're doing it wrong and/or using the wrong tool.
 

Moni

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The first thing many assume is a factory bad pot or pot damage by overheating.

Those are almost never the case.

It's almost always a soldering/wiring error.


I've been buying CTS pots in the thousands and testing/sorting each one for approaching a decade now. I know they are Asian-made and I wish there was a US equivalent I could use, but I have to hand it to CTS. The only factory-bad ones I've ever found were a few that arrived with a leg broken off and a few that were out of stated tolerance (but still worked fine, and I actually find these desirable for voicing some guitars). I have yet to receive a single one that just didn't work.


Pots can be damaged by overheating, but one has to really try hard to do that. They are a pretty tough electrical component. If you only have your iron on the pot for a few seconds, you won't damage it. If you need more than a few seconds to solder anything, you're doing it wrong and/or using the wrong tool.
The only bad pots I’ve seen is the metal contacts inside not lining up or bent so when the knob is off all the way it isn’t. Seen a couple on the bench where a previous so,during job dribbled down inside the pot from the tab by accident.

Agreed, usually silly things like that.

Just had a microphonic pickup customer concern issue with bleed through when turned off. I replaced the pots and fixed that, the previous owner had solder all over the place.
 




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