1956 X-50 electronics repair question

[glebert]

Howdy!

I just joined the forum but have been a Guild fan for 25 years or so, starting with my JF-55 acoustic that I bought new, last year got a 1967 F-30, and just recently got a project 1956 (or late 55) X-50. I've got the guitar playing acoustically, and it sounds and plays fantastic, but the electronics need some work. There is a wire (or more) broken inside, and the pots are totally frozen up. I was expecting to remove the pots through the f-holes, do whatever repair was necessary, and reinstall, but the pots are too big to fit through the f-hole (at least without forcing beyond my comfort level). Hmmm. My next thought was that the pots must have gone in through the hole where the pickup goes through the top. The pickup seems quite stuck in place though. It moves a little up and down and side to side but not much.

Any advice on how to repair/replace the volume and tone pots? If I don't need to pull the pickup I wouldn't

Note: I can measure the resistance of the pickup and it comes out at about 6.4k, which seems reasonable.

Thanks in advance,
Greg

 

[glebert]

OK, I got antsy and figured out a way to get the pots out. I was able to pry up the fingers that hold the back cover to the pot, and cut the wires soldered to the cover. With the cover off the pot was small enough to fit through the f-hole.

Anyone have a wiring diagram? The wiring as it was looked kind of..odd. The volume pot seemed like it was wired like a rheostat instead of a voltage divider like "normal" volume pots. Pots are both 500k, pot is 0.05uf.

 

[jp]

Sorry, glebert.

I wish I had some answers for you, but I don't have any experience with the single PU models from the 50s. Hopefully those that do will chime in.

Welcome to the forum!

 

[Walter Broes]

OK, I got antsy and figured out a way to get the pots out. I was able to pry up the fingers that hold the back cover to the pot, and cut the wires soldered to the cover. With the cover off the pot was small enough to fit through the f-hole.

Anyone have a wiring diagram? The wiring as it was looked kind of..odd. The volume pot seemed like it was wired like a rheostat instead of a voltage divider like "normal" volume pots. Pots are both 500k, pot is 0.05uf.

That's how they were wired, and it's pretty useless because as soon as you turn dow the volume pot even just a hair, everything turns to very dark mud.

The pots and harness go in/out through the pickup cavity. The cover is attached to the guitar's top with two small screws. If it won't come off, it might have shrunk. Unscrewing the pickup polepieces will show if that's the case. With the cover off, you'll see the pickup 's baseplate is attached to the guitar's bracing with another two tiny screws.

 

[Default]

I would hazard a guess that the tone control was wired that way because Al Dronge was a pretty fair jazz player and that was was "the" jazz tone at the time. That's what Aaron told me.
Jazz mud.

 

[glebert]

Thanks for the replies. Since I was able to get the pots and cap out without removing the pickup I'm going to just leave that alone for now. Wired in a volume pot with "normal" wiring, didn't have a second pot that was the right value and size so no tone control for now. Using newer pots I could fit it in through the f-holes after soldering the wires just fine. Similarly the big silver knob is just temporary. It's definitely player grade, a fair amount of binding rot, etc, but so far I'm loving the sound and the feel.