3/14/12

Gretsch G5120 Upgrades: TV Jones Pickups, New Wiring Harness and Compton Bridge (Pt. 3)

With the old wiring harness out of the guitar, we can move forward with the new one.

Above is the complete TV Jones harness and pickups ready to to.  You can get the pickups alone, but I wanted to do a small mod on the wiring, and I figured the new pots and switch would be better quality than the factory ones.  They are - the switch is a classic Switchcraft and the pots are CTS.  And the wiring itself is better quality.

I connected the pickups to the harness and did the 'Fezz Parka' tone control mod.  The mod rewires the tone cap so the tone remains the same when you lower the guitar's volume.  With a lot of guitar wiring, you lose treble as you turn the volume down.  By reversing two wires on the tone control, this problem goes away.  I do it on all my guitars.

If you do this work on your guitar, I encourage you to
use the TV Jones method of installing the pots and output jack.  It's just (vinyl?) tubing and a dowel.  They sell this as a package - I splurged and spent the $6 rather than try and piece it together myself.

If you look closely at the dowel, you see a clever bit of marketing.

You thread the tubing through the appropriate hole in the top of the guitar, and then up through the bridge pickup hole.

Then put the end of the tubing over the pot shaft.

You need to remove the pot's nut first, but leave a lock washer on.  I found I only had space for a couple tubes at once inside the guitar.

The four tubes for the pots are the same diameter, and the switch tube is smaller.

Pull the tube from the hole end until the pot comes up through the hole.  Simple and ingenious!

Here's my neck and bridge pickup volume controls in place.  The master tone hasn't been installed yet.

After you pull the pot up through the hole, you can slide a washer and nut down over the tube and fit them on the pots.

If I did this a lot, I'd get really fast at it.

Solder the new ground lead to the old one.  I used some shrink tubing to insulate it.

For the output jack, run the dowel into the guitar via the jack hole on the side of the body.  Then stick the tapered end into the jack and pull it through like you did with the tubes.

I had a heck of a time with my jack at first.  It kept falling off the dowel.  Then I realized I hadn't reamed out the jack hole - it was too small and the jack wouldn't pass through!

Here we have the pots and switch all in place, ready to put the pickups in.  I may not have mentioned this, but be sure to use a towel or clean rag on the top of the guitar to avoid scratching it.

The pickups come with mounting screws and springs.  Run them through the pickup ring surround and into the bracket on the pickup.

TV Jones sells the rings and also spacers to raise the height of the pickups.  You'll need one spacer for the neck pickup and one for the bridge.  The just sit below the mounting ring.

There are four holes in the corners of the rings that screws go into to hold the whole enchilada to the geetar.  On my 5120, two of them didn't line up exactly and I had to drill new holes.  No big thing.  The old holes are invisible under the pickup rings.

The rings are available in silver, gold and clear.  I opted for clear.  I figured I can paint them to match the guitar if I decide to later.

With the pickups in the guitar, I plug it in and see if it works.  (Actually I tested the harness on the workbench earlier).  Lightly tap each pickup with a screwdriver and test the pots and switch.  I managed to get it right the first time.  Whoo hoo!

And now for the piece of resistance.

I'm replacing the old tune-o-matic style bridge with a new Compton titanium bridge from Wayne Compton in Minnesota.  Wayne's bridges are all the rage for Gretsch players.  He sells them in brass, steel, stainless, and titanium.  There's usually a waiting list for the latter, but I emailed him to get on the list and he happened to have one in stock.  What timing.

I know, titanium!  Crazy, huh?  I would have gone with brass or stainless, but I had to try it.

It's a piece of art.  Really beautifully made.

All posts related to this project:

Part One - Removing original pickups
Part Two - Fitting bridge base and start of wiring
Part Three (this one) - Installing TV Jones pickups
Part Four - Finished!

6 comments:

  1. I've recently purchased some tv jones classics and ran into the problem of the bridge pick up not working. I soldered the thing numerous ways to diagnose the failure, but it was to no avail. The tech support was no help; I have a question: what wiring harness is that, and is there more than one type? I'd appreciate any help I could get at this point.
    be cool to get an email: filthybrain@gmail.com
    Thank you in advance.

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  2. Hi - I sent you an email response. Thanks!

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  3. Greetings. You have a very informative and fascinating blog. I was wondering if I could ask you a couple of questions related to the Gretsch Tennessean original wiring. Are you familiar with the stock wiring harness? I have a 1964 Tenny that has an obnoxious ground hum when plugged in. I managed to pull out the switches and pots and the wiring assembly but on the original setup there are sections of wiring that connect to the pickup by a banana clip arrangement. I wasn't sure if these connections are insulated enough to protect them from touching other wires. Someone used electricians tape to hold the two sections together but as you know over time electricians tape gets goopy and eventually dry out and fall inside the cavity of the guitar. I'm hoping to keep this original wiring and try to find the source of the ground problem and hopefully find a long term solution to resolve the problem. Now after saying all that I was wondering if you can share your thoughts on how to find and correct the cause of the ground hum and also if you have a long term solution on keeping the banana clips protected from coming apart and cause it to come into contact with another wire and potentially

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  4. Finished my sentence; and potentially short or cause a ground hum to erupt. I'm Interested in any proven solutions you can share. The pickups, switches, tone controls all function so I don't feel the need to replace with a newer harness.

    Thank you for your time related to this request.

    Mark

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  5. Hi Mark -

    Thanks for the kind words about the blog.

    Congratulations on having an original Gretsch! I bet it's really cool.

    Couple of things: I'd strongly suggest you properly fix the harness. Ditch the alligator clips and solder it properly. They are not a good idea in my opinion. Those clips may just let go when you least expect it. Ditto for the electrical tape.

    You can use shrink tubing to replace anything that needs to be insulated. That's part 1.

    Part 2 - your ground issue. Since the harness has been worked on before, there may be bad grounds. My guess is there are local grounds on the backs of the pots. These may have bad solder joints or bad wiring. You can test these by plugging the harness into an amp and wiggling the various connections until you find the culprit(s).

    If I were wiring it, I'd run all the grounds to one common point if possible - the back of one of the pots or the ground lug on the output jack.

    Also make sure you have a good ground going to the tailpiece.

    See some of my other posts on wiring Teles and Jazzmasters. The same stuff applies. (Do a Google search on site:crawlsbackward.blogspot.com and you'll see more wiring stuff.)

    If all else fails, you could find a diagram of an original Gretsch harness (TV Jones has them on his site I think) and just make your own harness with new wire and keep you original pots and switches. Such a fine guitar deserves to be set up right!

    Hope this helps!

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