Humming from Tone Pot on SX Jazz bass

[Eyesee7]

I hope you can make it thru this convoluted introduction but I had bought a Mojo replacement kit of pots/capacitor/jack for my SX Jazz. The screw on the new pots would not fit through the existing hole in the metal pickguard panel, so I decided to just change the jack since this was my first modification attempt anyway.

So I've got the new jack soldered in and while I used to previously have a slight hum when I removed my hands from the strings, I now have a more prominent, consistent hum (whether hands on the strings or not) and it is coming solely from the tone pot (the one closest to the jack - I had to solder one of the ton pot wires to the jack unit). When I turn the tone pot all the way off, the hum stops. So what can I do to remedy this, oh knowledgeable members of Talkbass?

[mech]

Right off hand I'd guess you have the jack wired backwards. Try reversing the wires on the jack.

Diagram...
http://www.stewmac.com/freeinfo/Elec...ms/i-0032.html

mech

[Eyesee7]

Mech, I had the wires reversed to begin with and got no response when plugged into the amp. I un-soldered them and switched them and was able to get amp response.

Also, when I touch the metal pickguard plate, the humming stops, don't know if that's any help.

[joeyl]

should be in the electronics section. Tone pot is affecting hum because hum is high frequency and turning the tone knob down is cutting the high frequency noise. So the noise if not coming from the tone, so that's out of the way.

Secondly, I don't know of mojo kits but cheap kits are bad in case they have cold solder joints, bad wiring and cheap caps. I would put the original pots and jack back and see if the hum goes away.

Touching the metal parts makes hum go away, and that just tells you that the bridge ground is good. You may just need to read some tutorials on how to shield your bass!!!


Hope this helps

[mech]

Eyesee7...can you post a pic of the wiring?

[Eyesee7]

Here's the wiring pics. The only thing I replaced is the jack, never attempted the pots because the bolt wouldn't fit thru the existing hole in the plate. So the only soldering I did was on the wires to the jack.

[mech]

I can't tell what's happening with the tone pot wiring. Can you take a picture of the wiring side of the tone pot from the direction of the arrow? The all black wires makes it difficult to tell where they are attached.

thanks, mech