Help diagnosing a problematic rewire.

[stubish]

So I rewired my strat as per the 'strat lovers strat' in the general schematics sub board. Only difference is that the grounds are to the shield, not the back fo the pot: guitarnuts2.proboards.com/index.cgi?board=schem&action=display&thread=3130

I also did the foil and glue shielding..

One i started testing. I Only get a signal at the bridge position of the 5 way (not sure which pickup it's coming through). and there's lots of hum, except what I touch my hand to anything that's supposed to be grounded (pots, bridge, pickguard screw etc). Also the hum gets MUCH worse when I touch my hand to the neck pickup.

So I've got not much idea where to start diagnosing, any help would be apprecieated. First time I've worked with push pulls, and actaully my first guitar rewire. I've installed a new pickup before but that's about the extent of it.

Thanks in advance.
Stuart

[newey]

stubish-

Hello and Welcome to Gnutz2!

I don't know that I have much in the way of advice here. A thorough troubleshooting is obviously in order.

First,

I Only get a signal at the bridge position of the 5 way (not sure which pickup it's coming through)

Let's find out which pup is active. With the switch in the bridge position, tap on the pickups with a metallic object like a screwdriver. This should disclose the active one.

Do you have a multimeter?

One thing to check is whether you have the jack wired the correct way. Reversal of the leads could explain some of your noise issues; it wouldn't explain the loss of the other pickups' signals. Did you shield the jack area rout?

Another thing is to check the pickguard assemblage with a meter while it's not mounted onto the guitar. This may disclose whether something is grounding out to your shielding that shouldn't be doing so.

[stubish]

thanks for the prompt reply.

1) yes, a multimeter is present.

2) from memory, the hum was more constant out of the pickup cavity. Actaully, I'm a little dissapointed with the shielding, I may scrap the cavitys and wait for some copper tape to arrive.

3) I did not shield the jack area rout. I figured with the two leads it should be ok. Hum does stop when I touch the jack.

[newey]

Let's wait for JohnH to weigh in here.

2) from memory, the hum was more constant out of the pickup cavity.

Do you mean that there was more hum (or, perhaps, a more constant hum) with the pickguard detached and therefore, "out of the pickup cavity"?

If so, it sounds like your shielding is having some effect. I wouldn't scrap it just yet anyway, we can't judge its efficacy until we get the guitar functioning properly.

[stubish]

correct on the hum. I'm off the case for tonight.. I'll get on it tomorrow some time. Hopefully have it up and running by saturday. Problem is I don't have a permenant home for the soldering stuff, so it's get it all out under the range hood time (ahh apartment living).

if you've got any more diags to suggest before tomorrow that would be great.

[stubish]

So after some more reading here's the plan for tomorrow. I'll try the ground to the vol pot washer trick. I'll double check everything while it's in bits. check all my solder joints. We'll see what happens from there. wish me luck!

[gitpiddler]

Hi and Welcome. Try it first with the 'blue' wires connected only to the jack sleeve wire. These are signal grounds, not shield grounds. You should run a shield connection to the jack. Cheers!

[JohnH]

stubish - theres good advice above. I would start with e multimeter, set it to the lowest ohms setting and test continuity from the jack barrel to each pot case, and all places joined by the blue ground wires, and also the strings.

Then check out which pickup is working.

Post a photo of the wiring, particularly being clear what is connected to the 5 way - there are various versions of that switch around. Your symptoms could be explained if the poles lugs are not where shown (ie those darker coloured in the diagram)

John

[stubish]

Ok, will do. Just one other thing. I'm a lefty. It shouldn't make a difference with the pots (as I don't mind them being a 'backwards' taper) but would that impact the switch poles? For references sake, the wiring I took apart was standard fender wiring, jumpered switch and all the wires where they 'should' be.

So I'd say maybe part of my problem is as follows.

1) I should wire the pots as in the scheme like so:


2) I should wire the switch like so:

Does that make sense? Or am I headed down the wrong path?

[wolf]

I figured I'd make that graphic a little bit more readable:

And welcome to GuitarNuts stubish

[cynical1]

Correct me if I'm wrong, but won't flipping the drawing and only changing the orientation of the lettering skew the wiring? ...or am I just having a Pre-Senior moment...

HTC1

[ashcatlt]

Yeah, it just confuses things. Flipping the image of the "fender" switch puts the commons on the wrong ends. Wiring it that way won't work.

You should wire it right handed and then rotate the switch 180 degrees.

[stubish]

really all the flipped diagram is used for is the 5 way switch. The pots will be wired as per the standard diagram.

[JohnH]

be careful with this left-right flippage!

Do you want the knobs to turn in the opposite direction to a righty? if so you really need antilog pots (rare), or linear pots at a pinch.

My suspicion remains centred on the 5-way switch. See on my diagram, the poles are the two diagonally opposite lugs furthest from each other? That style is less commnon (as i now know) than the type where they are the closer diagonal. Thats why we need to clearly understand the switch that you have - you should be able to look into it and figure out which lugs are the common poles, or use the meter to test connections.

cheers

John

[stubish]

Hi John,
I'm happy with the pots to be regular (reverse for me). I've wired up the switches as a righty so that's no problem.

I'll double check on the switch tonight with a meter if needed. could we number the switch ala stew mac?

[newey]

I'll double check on the switch tonight with a meter if needed.

You'll need to dewire it to do so. Rather than numbering the lugs, I use 4 colored Sharpies™ to color the 2 commons one color, the 2 "1" lugs another color, etc. This is easily visualized later when wiring. Just a little dot is enough.

[stubish]

Ok, so a fail tonight....

John, I do have the switch with the commons closer to each other. Tired to get things backward and orientated right for lefty, but didn't have much luck. Got much less hum but then I would get intermittant problems with switching. One swipe through the only thing that would work would be the bridge. then next time it would work kind of normal but with the bridge on all the time. The series switch worked the point that it would change the way the tones function. I have to be on the right track, but I"m not out of the woods yet. I actaully started again tonight, so I'm going to go back in much more carefully. It will take a few days.

Now to confirm. Is this what I'm looking for in the more 'normal' switch:
1 2 3 4
5 6 7 8

1) From the Middle left lug of the Vol Pot push pull (common)
2) Vacant
3) Middle Ground
4) Neck Ground
5) From the lower right of the tone1 push pull
6) Middle Hot
7) Neck Hot
8) to Volume pot Lug 3 (common)

thanks!
Stuart

[newey]

Now to confirm. Is this what I'm looking for in the more 'normal' switch:
1 2 3 4
5 6 7 8

1) From the Middle left lug of the Vol Pot push pull (common)
2) Vacant
3) Middle Ground
4) Neck Ground
5) From the lower right of the tone1 push pull
6) Middle Hot
7) Neck Hot
8) to Volume pot Lug 3 (common)

That's correct. As John noted, the question is whether the common lugs have been correctly assigned on your actual switch.

[stubish]

After doing a bit of work, I believe the tabs of the switch were shorting on the shield. Guitar is still in bits and I'm going to rewire soon. I'll isolate the switch area and see if there's an improvement.