Wiring help

Mugician

Active member
Messages
82
I wired my guitar exactly to this diagram:

tech02.jpg


And I'm not getting any sound. I've triple checked all the wiring. Bad pot? I only replaced one pot to back to a push-pull. When I crank the amp all the way up, I get sound from the guitar. How do I use a multimeter to check if the pot is bad?

 

Mugician

Active member
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82
So my dad helped me out with the multimeter. The pot is a 500k push-pull that I used as the volume control/master split. We were getting nothing across terminals 1 and 3, nor 1 and 2. So we tried another 500k push pull, and across 1 and 3 read ~.250. That's not right is it?
 

line6man

Senior member
Messages
6,443
It looks like the output and ground terminals are mixed up on the 3 way switch...

Swap the black and green wires on the 3 way switch, in the diagram you provided.
 

Mugician

Active member
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82
Are you absolutely certain? Because my guitar was wired like this before I put in the new pot.
 

exalted

Senior member
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723
The push-pull pot is the only new element in the schematic?

I'm no expert, but it looks like you've got the ground running in to your signal in the switch. The ground should be in the bottom terminal - not the middle. If I'm reading that right, the middle is a common terminal, so even when the switch is 'off', I think you still have the ground running into your signal.

But hey, I could be wrong.
 

Mugician

Active member
Messages
82
Well what happens if it's wired like this? The guitar was previously wired exactly to this diagram and worked fine, does it actually matter?
 

exalted

Senior member
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723
If I'm right, then your guitar will be dead, sound-wise.

Try switching the ground wire in the push/pull pot to the bottom terminals, and leave the middle terminals empty.
 

Patrick from Davis

Senior member
Messages
2,197
To test the pot, it should be the middle pin to one of the outside pins at 0 ohms and the other at close to the value of the pot with the pot turned all the way to one side.  Turn it all the way to the other side and the max value should swap with where the zero was.  They flip/flop.  It is probably an audio taper pot so the 50 % of a turn will not be half of the max.
Patrick

 

ognolman

Senior member
Messages
351
Do you have any shielding in the electronics cavities?  Sometimes it can touch something it isn't supposed to touch and cause a short.
 

Mugician

Active member
Messages
82
Well, if I'm not mistaken, the push-pull is dead. I couldn't get a reading on the multimeter - I tried for 2 hours last night...

As for the sound of the guitar before I put the push-pull in, it sounded great.
 

Mugician

Active member
Messages
82
ognolman said:
Do you have any shielding in the electronics cavities?  Sometimes it can touch something it isn't supposed to touch and cause a short.

Shielding paint, yes. What could it possibly be touching other than the pots? I didn't know this, I'll take another look.
 

ognolman

Senior member
Messages
351
I've had the copper tape shielding touching bare wire before, shorting out the circuit.  These can be tough to find sometimes.
 

blue313

Senior member
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2,824
exalted said:
I think you still have the ground running into your signal.
If I'm reading that diagram right, that's what it looks like to me.  The hot lead from the 3-way seems to continue all the way to where the ground leads from the pickups are hitting the ground on the output jack.

If its correct, then try cutting the connection where Ive put a red X.

edit: btw heres another diagram to consider
http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=2h_1v_1t_3w_1pp
 

Mugician

Active member
Messages
82
Blue13: I just did your little correction, and now I can't mute the guitar when the volume is all the way down. It's about the same as when the volume is at half. The grounding issue stopped though. I can't hear the buzz unless my fingers are off the strings now and it's quieter than the last set up before I did this little correction. Also, before, when I touched the shaft of the volume pot, I got LOADS of buzz even if I was touching the strings. Anyway. How do I fix the volume problem now?
 

blue313

Senior member
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2,824
The volume must not be grounding well. 

It looks like the ground wire that runs between the 3-way and the volume pot isn't tied into the other grounds.  Try temporarily connecting that lug to the ground on the backside of the pot.

If this fixes the volume issue, you may notice that its working in reverse and need to swap the connections on 1 and 3.  Hence the temporary part.
 

Mugician

Active member
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82
I'm not sure what you mean. You're aware the green wire is ground right? I'm just a little confused here.
 

exalted

Senior member
Messages
723
SD has a pretty detailed schematic for what you're trying to accomplish, and it looks like it has a few differences from yours. I'd try this schematic out and see what happens.

http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=2h_1v_1t_3w_1pp

 

blue313

Senior member
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2,824
Is that a Les Paul style 3 way? If so, the green wire is the hot lead and the one on the backside is the ground lead.
 

exalted

Senior member
Messages
723
Blue313 said:
Is that a Les Paul style 3 way? If so, the green wire is the hot lead and the one on the backside is the ground lead.

That's not necessarily true.

I have an 'angled' LP-style switch.
It has two rows of terminals, three on top, two on bottom. Like this:
o  O  o
o    o

Logic (and looking at other diagrams) told me the upper terminals were input-output-input, and the bottom terminals were ground.

After much trial and error, I figured out that it was actually input-ground-input on the top, and output-output on the bottom. His diagram could be right, if that's the case.

 
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