I have on my bench a late 70's (pre Ernie Ball) Music Man Sabre 1 electric guitar. Sometime before it came into the shop, someone decided they needed to replace the input jack, but it never quite happened, and the loose wires were still hanging when I opened it up. The 3 way switch was also partially burned up from someone's previous work, so I replaced that as well. It has a preamp - I found a drawing of the correct wiring for this model and used it to be sure nothing else had been monkeyed with.
Well, imagine my surprise when after all this work both pickups are hot in all 3 switch positions! I have gone over the wiring and the diagram several times today - examined - re-examined - and as far as I can tell everything is as it should be. I am pretty good with electronics in guitars, but this one has me stymied.
Does anyone have any idea what I have done, who might be good to talk with about this, or if it could it be something gone south in the preamp causing this problem? Many thanks for any suggestions!
We need some pics and diagrams , flying blind .
It sounds like the selector switch is either wired incorrectly or defective. I believe this is a typical Fender style 3 position switch so it is easy to visually follow the signal path. The pickups themselves are passive so I would wire the output from the switch (which would feed the preamp) to an amp to make it easier to see what's what.
See attached photos. 2 of these are of the actual wiring, one is the template for how this is supposed to be wired.
My confusion seems to be with the phase switch - I guess I don't understand how all those lugs are supposed to work with each other. When I put a meter to it, they all seem to be coming back to the 3 way switch thru the white wire on one side and the yellow on the other irregardless of the phase switch position.
It's a strange setup, it looks like the phase switch also switches on both pickups when in the out of phase position
. It would be possible to wire the switch wrongly if you had it rotated 90deg. To understand the phase switch , the hot and cold wires go to the middle contacts , and in one pos'n they connect hot to 3 way and cold to ground , and in other pos'n they get hot to ground and cold to 3 way .
In this setup it looks like the lead pickup gets added in ,in the out-of phase pos'n via the yellow wire so you get out-of-phase sound in rhythm and middle pos'n ? Sorry this is not helping ! The purple wire from the switch to preamp is the output of 3 way , Id cut it and use alligator leads to hook up a lead to an amp , one from black link on 3 way to tip of lead , and one from ground to sleeve of lead , see what you get in 3 pos'ns .
Thanks for the help - I was just wondering if the phase switch was not laying the same as the drawing. Fortunately, it was.
I took off the purple wire and tried the pickups - the 3 way switch worked correctly without the preamp. So I wired the purple wire back into the circuit - low and behold, the pickups work as they should!
At first I thought it was a voodoo repair (you know, you take it apart and find nothing then put it back together and now it works) - then I discovered the problem. I am ashamed to say it, but here is is for anyone else who works on one of these - if the phase switch is engaged, both pickups are hot in all positions! when it is not, they work as they should. Whoda thunk it?
Many thanks to the folks who made suggestions - I am going back to my acoustic repairs!
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