Could use some help with a grounding issue

[Jakke]

I'm wiring a pickup into my newly aquired Fender Esquire, and I have encountered a buzzing issue that I decided had to do with that there was no ground to the bridge (buzzing increasing a lot when I touch the bridge or strings, but decreasing/stopping when touching the control plate). So I taped a wire beneath the bridge, and soldered it to the volume pot, only to find that the ground shorts the entire circuit. What am I missing here? Does anyone have any pointers?

I got the advice to reverse the hot/ground wires on the jack, but all this accomplished was to switch the buzzing to when I touch the control plate instead.

 

[Greg_L]

Re: Could use some help with a grounding issue

Did you solder the ground to the wrong pot terminal? Seems like it, no? Check continuity at all ground points.

 

[Jakke]

Re: Could use some help with a grounding issue

I soldered the ground to the pot itself, just as the wiring diagram says I should*

Esquire

Continuity, how do I check for it?

 

[Greg_L]

Re: Could use some help with a grounding issue

I soldered the ground to the pot itself, just as the wiring diagram says I should*

Esquire

Continuity, how do I check for it?

Well, my wiring/electrical knowledge is rudimentary at best, but I do know that everything on the guitar goes to ground through the input jack, through the cable, and through the amp. Double check your wiring. So I'd put one end of a multimeter set to ohm scale at the ground lug of the input jack, and then with the other end touch every other spot that is supposed to be a ground. Start at the bridge. Find where there's no continuity to ground. Continuity will show as a very low resistance reading on the multimeter - preferably 0. Wiggle wires around. You might simply have a bad solder joint. Every blob of solder is a potential bad spot. Pickups and pots pick up interference. All that messy noise is supposed to go to ground via shielding and proper wiring. You touching the guitar and the noise changing means you're acting like a conductor in some way. You just gotta find why.

 

[Jakke]

Re: Could use some help with a grounding issue

Don't have a multimeter, but I did check what joints gave off buzzing when touched, it's the hot joint at the input, the joint connecting the volume pot to the switch, and the lug leading to the pickup. Pretty standard stuff, the ground is also buzzing however when touched, and I'm wondering if it is supposed to do that...

I did throw together a visual representation over the buzzing joints:


I have to apologize if my knowledge is quite rudimentary as well, but even though I can switch pickups, I don't know enough to troubleshoot when something is wrong.

 

[GEARHEAD8]

Re: Could use some help with a grounding issue

Hi , It might be your switch not grounding to the control plate, scuff the plate and switch a bit with emri paper and recheck the ground and do the same on the bridge then solder a non-stranded wire. One other thing , check your guitar cable . It should only be shielded at one end ( i.e. 2 conductors plus shield wire). Planet Waves and many others have an "instrument-end" label , your pickup is and inductor and will pick up noise much like an antena , more so because it is a non-humbucker/single coil . The shielding creates a "Faraday cage" and blocks exterior noise. another good idea is to shield the control and pickup cavities with copper tape , I did my Tele and a bunch of Strats and have 99% results.

 

[Jakke]

Re: Could use some help with a grounding issue

Should I rough it up on the upper side, or under?

Also, can anyone help figure out why the ground shorts the circuit?

 

[ParameterMan]

Re: Could use some help with a grounding issue

Also, can anyone help figure out why the ground shorts the circuit?

Somehow your bridge is connected to hot. Connecting it to ground shorts everything out. The points in the circuit you circled that buzz when you touch them are correct. If the bridge buzzes like that when touched it's also connected to hot.

The simplest way this can happen is if you install a pickup that has one wire designated as the ground, ie. connected to the baseplate(and thus the bridge when installed) and you accidentally got the wires flipped and ran that one to the switch instead of ground.

 

[Jakke]

Re: Could use some help with a grounding issue

That was exactly what had happened. I might petition Lundgren to mark their wires next time.


Thanks all for your help and time

 

[dr. ad]

Re: Could use some help with a grounding issue

for future reference, many multimeters will have a mode set to beep when resistance is 0/continuity.
check what the mode buttons do when the meter's set to measure resistance, and/or look for a speaker or soundwave type symbol on the dial.
ie:
) ) )