Disappearing bridge pickup: what's going on?

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HorseyBoy
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Disappearing bridge pickup: what's going on?

Post by HorseyBoy »

Trying to figure out what's haunting my Greco Les Paul.
When I got the guitar, the bridge pickup wasn't working. The seller had a pair of boutique pups in there but removed them and reinstalled the original Maxon pups before he sent it, so I figured he'd just buggered up the wiring. So I re-did the wiring, swapping to the 50s wiring style was I was at it, and that seemed to do the trick. Except it didn't last. The bridge pup went on me again, but it was intermittent - so if I left it a while it would come back. But then the neck pup would go on and off as well. "Aha!" I thought. "It's a dodgy switch!" So I got a Switchcraft switch and wired that in. While I was at it, I put a couple of Orange Drop caps in (because I had an idea they might be leaky and contributing to the problem).
For two weeks or so, everything was great and I figured I'd solved it. But then I took the guitar to a rehearsal room over the weekend and the bridge pup went again, although this time the volume dropped off first before it died completely. I fiddled with the switch and the volume knob over the course of the rehearsal and the bridge pup came back and stayed back.
At that stage I figured it had to be either the volume pot or the pickup itself, so last night I wired a new volume pot in. Seemed to work fine, but then the volume dropped on the bridge pup again and I'm back to square one.
It's odd, because when I first got the guitar, when the bridge pup went, it was gone completely - no volume at all, no measureable signal. Almost like it was shorting out. But now there's a dramatic drop in volume rather than a complete loss of signal.
Anyone got any idea what could be going on? All that's left is the pickup, I guess, which sounds really, really great when it works. But maybe one of the connecting solder joints is flaky. I don't have a big enough soldering iron to pop open the cover and check and I'm not sure I'd even know what to look for so I'd have to take it to a luthier to get that checked out.
One thing I think could be an issue is the quality of the old Maxon braided cable. It's very different to any braided cable I've seen before. The braided shielding is very flimsy, and underneath it there seems to be intricate wraps of cotton strands. Unwrapping it is an absolute nightmare, and you end up with strands of cotton everywhere and a thin bit of wore in the core. There's a chance that a stray wire from the shiedling is pushing through into the core, which obviously wouldn't be good. So I'm wondering if it's possible to replace that braided cable with something better.
Anyway, I thought I was going about this logically but now I'm not so sure. Any help appreciated.
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skelt101
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Re: Disappearing bridge pickup: what's going on?

Post by skelt101 »

Horsey,
Sounds to me like you are approaching this logically. Are you getting a consistent resistance reading from the pickup?
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HorseyBoy
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Re: Disappearing bridge pickup: what's going on?

Post by HorseyBoy »

skelt101 wrote: Wed Mar 28, 2018 11:23 pm Horsey,
Sounds to me like you are approaching this logically. Are you getting a consistent resistance reading from the pickup?
Yeah, except for when it cut out completely early on, it's always measured at a steady 8k.
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Zuff-1A
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Re: Disappearing bridge pickup: what's going on?

Post by Zuff-1A »

Sometimes tiny loose metal hair from braided cable causes problems, can be pierced through
cotton etc, check carefully that. Or ends of the cables has been soldered several times and should be cut off
because better connection
In some cases just pickup coil wire may halfly broken and pickup may needs rewind unfortunately.
You can see it if the reading is not stable.
Connect pickup directly to guitar cable and then play to see
if pickups are ok
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HorseyBoy
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Re: Disappearing bridge pickup: what's going on?

Post by HorseyBoy »

^ Thanks, Zuff. Yeah, it has to be a problem with the wiring or the pickup itself. My current plan is to desolder, cut the ends of the cables and try again. I might have to extend the cable with some normal wire, which I seem to remember doing to another guitar years ago. I've got a feeling it could be the cable - the amount of stray wires from the shielding and tiny strands of cotton going in all directions is insane. And putting in the new volume pot seems to have made everything worse, not better, so I'll need to be extra careful.
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Dr Tony Balls
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Re: Disappearing bridge pickup: what's going on?

Post by Dr Tony Balls »

Have you tried replacing the whole thing with a telecaster? j/k j/k j/k

If the problem is intermittent and its wiring you might just wanna replace the entire shielded cable, but that might not be a job everyone wants to do. Otherwise i might just nip the whole thing in the bud and replace the pickups or pickups. There are some amazing sounding humbuckers around nowadays that dont break the bank. The Stewmac Parsons street ones are phenomenal and a set is like $120.
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HorseyBoy
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Re: Disappearing bridge pickup: what's going on?

Post by HorseyBoy »

^ I did think of going the Tele route, believe me!
I really want to keep the pickup because it sounds great, but you're right about me not wanting the replace the whole braided cable myself. I'd be terrified of stuffing it up. If I end up doing that I'll have someone do it for me. Guess I need to make sure the pickup is fine first.
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HorseyBoy
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Re: Disappearing bridge pickup: what's going on?

Post by HorseyBoy »

Quick update on this. Took the guitar to a luthier friend tonight and I think we might have isolated the problem as a dodgy connection underneath the pickup cover. First we snipped off a mangled end of braided cable at the pot (the hot wire from the pickup) and wired it back up. That worked for five minutes or so, but as I was playing the guitar the pickup went again. I kept playing while we tried to figure out what was going on - and a good firm whack on the pickup cover got the sound back immediately. So it's definitely a connection to the pickup, maybe a dodgy solder joint. Left the guitar with him so he can crack the cover open and have a look.
Fingers crossed!
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devnulljp
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Re: Disappearing bridge pickup: what's going on?

Post by devnulljp »

Sounds about time for a nice set of Reilanders or ReWinds to me.
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HorseyBoy
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Re: Disappearing bridge pickup: what's going on?

Post by HorseyBoy »

devnulljp wrote: Sat Mar 31, 2018 8:54 pm Sounds about time for a nice set of Reilanders or ReWinds to me.
If these Maxon pups (U-1000s, aka Ibanez Super 70s) didn't sound so good, I'd think about it. But they're awesome.
And I think it's finally sorted. :freakout:
Turns out one of the link wires coming off the coil was broken:

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