Johnny Marr wiring help please!

[El Reclusa]

Hello all.

Just finished (mostly) a Jag build with an MJT body, vintage Musicmaster neck, and Novak pickups. So far, for having not even set it up yet, it's great! The only hitch is -and I've quintuple checked against the wiring diagram- with the 4 way switch, I'm getting neck only and three both pickup settings, with no bridge only. What would cause this? I'm flummoxed as I see nothing obvious wrong. Any help would be super appreciated. Thanks!

[hpr_hpr]

1. What is the diagram you are using? link / actual picture?
1a. what are the different positions supposed to give you . . .

2. I get you are getting sound in all 4 positions of the switch BUT 3 of those sound like both pickups are active?

I don't suppose you have a multimeter?

First things first, tap test . . . set the switch, tap both pickups carefully with a metal object (wrapped in something if you want to make sure you don't scratch anything) record if one is louder than the other for each position of the switch (so you end up with a 2 column, 4 row matrix with loud, soft, no sound in each cell, columns are pickup, rows are switch position).

EDIT -----------------------------------------------------------

OK here are 2 variations of the 4 way switch diagram:


In you case what is labeled neck hot lead here probably comes from the switches in the upper bout . . . not sure without the actual wiring diagram . . . BUT . . .

Hmm, you could have a short in your switch . . . do you have a multimeter (or continuity detector = 2 leads, a battery and a bulb) to test that? Unlikely though . . .

. . .given the above diagrams it seems to mean that neck COIL START (ground lead above) is permanently connected to actual GND as neck COIL END (hot lead above) is alway connected to the volume (so switching the neck PU off is done by disconnecting COIL START from GND which doesn't seem to happen in your case). OK check ONE . . disconnect the neck COIL START (ground lead) from where ever it is connected an check that you now get the bridge PU signal in the bridge only and parallel settings of the pickup switch (and no signal in the other two positions) . . . if that's true you have now verified that the problem is the switching of the COIL START (ground lead) of the neck PU.

If you haven't yet . . . and plan to do more (re)wiring . . . get a multimeter, you only need a very basic one that costs $6 and they are REALLY handy to find (or rule out) specific problems.

EDIT 2 -----------------------------------------------------------

... just had a look at the Novak pickup page . . . seems they have 2 leads BUT they do have some electrically conductive parts on the bottom . . . did you perchance shield your cavities with copper foil? If so you may somehow have a connection between the foil and the bottom of the pickup . . . I'm assuming you grounded the foil correctly . . . . . . put a piece of electricians tape (any adhesive tape will work for testing at the very least) over the bottom of the neck pickup and see if that solves the problem.

[El Reclusa]

Thank you. I'll post pics/links from an actual computer a bit later.

I think my problem is the Fender JM Jag diagram is for non rwrp Bare Knuckle pickups. After perusing some other threads I think my problem is the claw of the neck pickup needs to be disconnected from the bottom of the pickup as the Novaks are rwrp...

[hpr_hpr]

If your 'claw' is grounded then there is your potential problem . . . the claw is making contact with the COIL START wire and thus COIL START is always connected to GND regardless of the state of the switch . . .

[mylona]

Johnny Marr did not want RWRP on his pickups in the JM Jag as he said with RWRP one pickup pole would be attracting the string while the other was repelling it. He said he could here this and wanted a much more pure string vibration with both pickups wound the same.

[mylona]

I have just replaced the Fender pickups in an American Pro Jag that has the 4 way selector. It works OK. But what I would say is that the ground soldered to the claw is not connected to the coil ground via the pickup. They are only connected via the central earth point, that is on the back of the volume pot or where ever you have decided to ground. If you look at the underside of the claw there are holes around the poles so the claw is insulated from the windings.

[hpr_hpr]

Here's a pic of some Novak Jag PUs



Would not be surprised if the solder points on the bottom would make contact with the claw unless precautions are taken . . . then again I've never worked with Jag pickups so what do I know

Johnny Marr did not want RWRP on his pickups in the JM Jag as he said with RWRP one pickup pole would be attracting the string while the other was repelling it. He said he could here this and wanted a much more pure string vibration with both pickups wound the same.

Not going to debate that, but I don't believe the amount of magnetic force from a pickup would have an effect that could be heard because of the deformation of the string . . . . . now a pickup magnetizes the string and the vibration of magnetic string is picked up through the coil . . . the magnetism of the string obviously extends throughout the string so I could believe that there is a difference in the intensity of the magnetic force of the string can exert due to the reverse polarity of the pickups as the two induced magnetic forces would 'fight' each other instead of reinforcing each other as with PUs with the same polarity . . . .

Also the idea that one PU attracts and the other repels the string presupposes that the string is a magnetic entity in it's own right. This is clearly not true, the only magnetism a string has is induced by the pickup.

[mylona]

I think the pic of your pickup shows the problem. The coil is not switch grounded but permanently grounded by the claw. So put a thin strip of insulation tape over the offending link on the pickup base, refit the claw and hopefully you will be playing.

[El Reclusa]

viewtopic.php?f=7&t=86239&start=30

I'm using the same Fender diagram referenced in this thread- see the bottom couple of replies on page 3. I have similar questions to those last two on page 3. I haven't had the free, undistracted, non-exhausted time to do any more to the Jag yet, but I have been thinking about it a lot. My Novak neck pickup I have the ground from the claw and the pickup ground connected, and I am 98% sure disconnecting those two will solve my problem.

I *am* a little confused by the area marked with a question mark on the diagram at the bottom of page 3 on the thread referenced above though, near the bridge pickup. I assumed based on the diagram that was the short ground wire from the brass shield, and that in this wiring scheme it's NOT connected at all, as it's not shown connected to the pickup or claw or anything. I just insulated the end of that wire with tape and disregarded it.

At some point, once I get a few free minutes to sort out linking photos correctly here, I'll do so. Aside from the wiring weirdness and needing a much better setup, I'm really happy with this build.

Thanks all!

[El Reclusa]

viewtopic.php?f=7&t=86239&start=30

I'm using the same Fender diagram referenced in this thread- see the bottom couple of replies on page 3. I have similar questions to those last two on page 3. I haven't had the free, undistracted, non-exhausted time to do any more to the Jag yet, but I have been thinking about it a lot. My Novak neck pickup I have the ground from the claw and the pickup ground connected, and I am 98% sure disconnecting those two will solve my problem.

I *am* a little confused by the area marked with a question mark on the diagram at the bottom of page 3 on the thread referenced above though, near the bridge pickup. I assumed based on the diagram that was the short ground wire from the brass shield, and that in this wiring scheme it's NOT connected at all, as it's not shown connected to the pickup or claw or anything. I just insulated the end of that wire with tape and disregarded it.

At some point, once I get a few free minutes to sort out linking photos correctly here, I'll do so. Aside from the wiring weirdness and needing a much better setup, I'm really happy with this build.

Thanks all!

I should clarify, I mean separating the neck pickup and claw grounds from each other, not entirely from the guitar!

[timtam]

I *am* a little confused by the area marked with a question mark on the diagram at the bottom of page 3 on the thread referenced above though, near the bridge pickup. I assumed based on the diagram that was the short ground wire from the brass shield, and that in this wiring scheme it's NOT connected at all, as it's not shown connected to the pickup or claw or anything. I just insulated the end of that wire with tape and disregarded it.

Without reading the other thread, I believe it grounds the shielding plate under the pickguard. The wire is grounded in the cavity and then contacts and grounds the plate by being sandwiched between it and the body. I could be wrong ... but you can see a similar technique used to ground the trem (and therefore bridge and strings).

I also believe I'm correct in saying there is no need to separate the coil from the claw on the bridge pickup on the Marr - only the neck needs that (see the separate green wire from the neck's claw). In fact you can see one side of the bridge coil grounded to the volume pot. It doesn't hurt to separate them on both pickups though.

[El Reclusa]

I *am* a little confused by the area marked with a question mark on the diagram at the bottom of page 3 on the thread referenced above though, near the bridge pickup. I assumed based on the diagram that was the short ground wire from the brass shield, and that in this wiring scheme it's NOT connected at all, as it's not shown connected to the pickup or claw or anything. I just insulated the end of that wire with tape and disregarded it.

Without reading the other thread, I believe it grounds the shielding plate under the pickguard. The wire is grounded in the cavity and then contacts and grounds the plate by being sandwiched between it and the body. I could be wrong ... but you can see a similar technique used to ground the trem (and therefore bridge and strings).

I also believe I'm correct in saying there is no need to separate the coil from the claw on the bridge pickup on the Marr - only the neck needs that (see the separate green wire from the neck's claw). In fact you can see one side of the bridge coil grounded to the volume pot. It doesn't hurt to separate them on both pickups though.

Grounding to the plate under the guard would make sense, though I don't think the wire on my shield is long enough to reach that far? Then again, I didn't really try so there's that. That would sorta complete the Faraday cage effect though. Interesting. In any event, I feel confident that wire isn't the source of my troubles. I'll try separating the pickup and claw grounds on the neck pickup tomorrow evening and report back. Cheers!

[hpr_hpr]

I also believe I'm correct in saying there is no need to separate the coil from the claw on the bridge pickup on the Marr - only the neck needs that (see the separate green wire from the neck's claw). In fact you can see one side of the bridge coil grounded to the volume pot. It doesn't hurt to separate them on both pickups though.

Yep, because bridge is switched at the COIL END (hot) the COILD START (ground) can stay connected. It's only the neck pickups that's switched off by disconnecting the COIL START from GND - COIL END is permanently connected - so if COIL START is permanently connected to GND (by a short at the base to the claw) that pickup can not be switched off which would lead to the results reported so far.

Grounding to the plate under the guard would make sense, though I don't think the wire on my shield is long enough to reach that far? Then again, I didn't really try so there's that. That would sorta complete the Faraday cage effect though.

And yes to get the full effect from the shielding the plate under the guard also needs to be connected to ground somehow . . . it doesn't matter where but you have to tie it in somewhere. So if the wire isn't long enough to get to the exact spot indicated . . . just find another convenient spot . . .

[El Reclusa]

FINALLY got enough free time to dig in, and got the wiring FIXED!

In the end all I had to do was, as speculated above, disconnect a wire on the neck pickup, as the Novaks I have are RWRP and the Bareknuckles in the Marr are not.

As soon as I get a chance to sort out how to post photos here I will. I still need to do some final setup and intonation but so far I really dig the Jag. The added series position with the Marr wiring is really cool; I'm glad I did it.

[edwardskim]

Can we please see some pictures of the build thus far? I'm looking at putting a vintage Musicmaster neck on a Guitar Mill body.