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Wiring a Telecaster With Coil-Shunt Humbucker Switching

I mentioned that the Tele body came to me with a humbucker in the neck position.  It was an older Golden Age (Stew-Mac) model.  I didn't realize it had the older style 2-conductor wiring.  I wanted to wire it with a coil shunt, so I wound up getting one of their 4-conductor models.

You can modify a 2-conductor humbucker to do a coil shunt, but I didn't want to mess with taking the pickup apart, so I took the easy way out.

(Some folks call this a "coil-cut."  Either term is acceptable, but a "shunt" is really what we're doing electronically here, so it's a little more precise.)

Anyway, you can see the 4-conductor, plus shield wiring in the top picture.

I'll be wiring the pickup through a push-pull switch so I can have the full humbucking tone, and switch to shunt the stud coil out so it will function as a single-coil unit as well.

It's easy to mount the pickup to the Tele pickguard using the screws that come with the pickup.

We need to run a ground wire from each of the two pickup cavities to the star ground that will be in the main control cavity.

You can do this a couple of ways - I used three methods just to demonstrate.

Here's one way - I did this on the bridge pickup cavity.  This works well if you don't have any lugs handy - you can fabricate your own.

Just wrap a lead around a washer, and solder it.  Then run a screw though the washer into the body of the guitar.  This screw was already on the guitar from the factory, so I reused it.

You could also just wrap the lead around the screw, but that's a bit less reliable.  You don't want to be playing the solo to "Communication Breakdown" full volume at the Concertgebouw and suddenly have the ground let go...and you get huge hum.  Not good.

Method two.  Just solder the lead straight to the shielding.  Unlike the grounds on those old Fender amps, this is easy to solder and makes a reliable connection. 

This one is on the neck pickup cavity.

Now we run all our grounds and pickup leads into the control cavity.  And here's the third method I used - put crimp lugs on the lead ends.

Even those these are crimp leads, I still like to run some solder onto them for an extra measure of peace of mind.  Lugs are the most reliable ground connection of the three methods.

Now you see why it's called a "star ground."  All of the ground leads come together in one point and makes a 'star' of sorts.

I think there are 6 leads here.  This is solid and reliable, and the best approach for low noise.  Be sure you test all the leads for continuity before you put it back together.

Notice the thin lead coming in from the right side of the picture - more about that in a second.

Here's how I wired the output jack.

On the left you see a piece of RG-174 coax cable - the thicker one.  The center 'hot' connector goes over to the right lug - which is the tip, or 'hot' lug of the jack.

The shield of the coax and a thinner gauge lead both go to the ground lug of the jack.

On the other end, the shield of the coax is not connected to anything.  The 'ground' lead goes to the star ground.

The shield is only grounded at one end.  If you ground it at both ends, you'll have a ground loop, which produces hum.  I see a lot of gear where it's grounded at both ends.  It's not good practice to do that.  That's why I have a separate lead running back to ground.  That's the one I referenced earlier.

Now we just need to wire the switch and volume and tone pots.  It's pretty straightforward - you can find a Tele wiring diagram here and elsewhere.  The only thing we have that's different than the diagram is that the neck pickup is a humbucker instead of a standard Tele neck pickup, but it's essentially wired the same way.

Check out my new wire-bending pliers!  Now I can make precise bends in leads.  Where have you been all my life? 

Here's the whole thing wired up and ready to go.

See the coax with the blue shrink insulation on it?  That's the lead from the center (hot) lead of the volume pot going to the output.  The insulation is to ensure the shield doesn't touch anything.

Your humbucker lead colors may vary from these - but these colors are accurate for the Golden Age, and also for Seymour Duncan pickups.

On the switch, the red and white humbucker leads go to the center tab, and the black lead goes to the top most tab (nearest the control plate).  The green and the shield both go to the star ground.

When the switch is down, the humbucker is in normal mode, and when it's up, the stud coil (without the screws) is shunted to ground.  I wanted the screw coil to be active since it's the closest to where the 24th fret would be - the second harmonic node.  I figured that's a good thing for tone.  Or something like that!

I could have possibly made some of the leads a little shorter, but I like to have enough so I can open the controls without unsoldering anything if for when I decide to do mods.  I put an .022 tone cap in it - I'm out of .033 Russian PIO caps!  I need to hook up with my Ukrainian connection soon.

The final touch for the wiring is this Rutters output jack cup.  Super nicely made - better than an Electrosocket!


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