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Installed jb sh4, super bad feedback/hum

Jsnow08

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Installed jb sh4, super bad hum
Hey guys, hoping someone could help me out with this. I recently installed a jb sh4 pickup into the bridge position of my strat. The setup is single humbucker single volume, no tone no switch no other pickups.
I have the red and white wires soldered together and taped off. The green and bare wires are soldered to the pot (used shrink tubing around them because I know the bare wire shouldn't be exposed). The black wire is soldered to the first tab of the pot. A wire is soldered from the tip of the output jack to the 2nd tab of the pot. The third tab of the pot is bent back and soldered to the pot. A wire is soldered from the sleeve of the output jack to the pot. The pot is grounded to the tremelo and to that little tab that screws into the body of the guitar.
I followed seymour Duncan's diagram for one humbucker one volume precisely. I have checked and re checked everything.
The hum does not stop when I put my fingers on the strings so I don't think it's a ground issue. It just sounds like the guitar is feeding back uncontrollably. (It happens when my amp is cranked for practice).
In order for it to stop I have to stand like ten feet away from my amp. This did not happen with the invader I had or the dimarzio x2n. I have had hot pickups before so I know it's not the fact that its a high output pickup. Plus my buddy plugged in his les Paul that has a jb sh4 in it and there was no problem.
Anything I may have missed?
Thanks guys
 
The only thing that sounds odd is "The pot is grounded to the tremelo and to that little tab that screws into the body of the guitar. "  It may be the phrasing, but I'm not sure what you mean by this.
It still wouldn't surprise me if the jack is backwards.
 
Some guitars have a tab in a control cavity ot trem cavity that's screwed in to contact the shielding (painted or copper tape).

AutoBat said:
The only thing that sounds odd is "The pot is grounded to the tremelo and to that little tab that screws into the body of the guitar. "  It may be the phrasing, but I'm not sure what you mean by this.
It still wouldn't surprise me if the jack is backwards.
 
AutoBat said:
The only thing that sounds odd is "The pot is grounded to the tremelo and to that little tab that screws into the body of the guitar. "  It may be the phrasing, but I'm not sure what you mean by this.
It still wouldn't surprise me if the jack is backwards.

its just a small tab that is screwed into the control cavity of the body like Neo Fender said. Just another ground. and no the jack is not backwards. Like I said, checked, re-checked and re-re-checked everything. Could it just be a bad pickup? man that would suck
 
I can't tell if you're talking about "hum" or "feedback". They are two completely different things unlikely to be caused by the same thing.
 
Seems unlikely to be the issue, but it seems possible this is a case of the old "hot and ground connections on the jack are mismatched" issue.  If you try reversing your connections at the output jack, see if you get any better results.
 
drewfx said:
I can't tell if you're talking about "hum" or "feedback". They are two completely different things unlikely to be caused by the same thing.

Perzactly. And we don't know if there's any output at all other than hum or feedback. Can you hear the strings?
 
Do you have a multimeter?  If you do, plug a cord into the guitar and check the continuity between the sleeve on the cord and the strings.  Then do it again on the tip on the cord.  The sleeve should ring out, the tip should not.  That will let you know if the grounding on that section is correct.  If backwards, well there you go.
Patrick

 
90%

You've got wires touching somewhere, maybe one little escapee from stranded wire touching among the lugs of the tone or volume pot, or a bare wire touching to ground around the jack? Just follow the signal geographically, the pickup bone's connected to the tone bone connected to... etc. Magnifying glass...
 
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