Gretsch Junior Jet Controls Upgrade

Gear
27

Can you send me a schematic of how you wired the controls with the individual volume knobs, treble knov and jack ?
Thanks
Rich Vineyard

2 Likes
28

It’s wired just like a jazz bass. A search for “jazz bass wiring” will turn up a gazillion diagrams, step-by-step videos, etc. Here is one such diagram, courtesy of Stewmac:

Oh, and welcome to the forum! :smiley:

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29

So that i understand, you changed the three way toggle switch to a rotary dial tone control, then changed the other two rotary pods to volume controls fot the individual pickups.
Is that correct.

30

Essentially yes, although here is exactly what happens:

  1. The existing volume control becomes the neck pickup volume.

  2. The switch is replaced with a pot that becomes the neck pickup volume.

  3. The tone control remains the tone control.

This layout seemed logical to me, although you can arrange the pots any way you like as long as the wiring is correct.

2 Likes
31

Thank you very much for your help. I like that setup and am going to try and do it. So all I need to follow is the Jazz wiring schematic you sent and purchase 3 new pods. Should I go with the 250 or the 500 pods? Should I change the stick jack also you think.

Again new at this but willing to try. Thanks for replying so quickly.

Rich

32

Good question. When I did the upgrade I was under the impression that the pickups were “mini-humbucker” dual coil units.

We now know that this is not the case; that the pickups are in fact single coil units.

That being said, the original pots metered at 422K ohms and I used 500K pots. They work just fine, but if you feel like experimenting . . .

I replaced the jack with a True Tone multi-contact jack because I had things apart and why not? However there is nothing wrong with the original jack.

The only scary part of this upgrade is enlarging the holes for the pots. Use a tapered reamer and work very slowly!

1 Like
33

I’m noticing a hum or interference at different volumes so i lined the cavity just with copper foil but i still get the interference, could it just be the stock pods you think. 1 also installed a set of flat wounds do thats not the issue I’m sure.

34

Is your foil all connected to ground in some way?
If not, it won’t help you.

2 Likes
35

How do i do that ?

Rich

36

Do I solder a wire from the foil to one on the pod cans?

37

You can do that, or the ground on the jack, any ground point will do.

1 Like
38

Thanks Ill try that

39

I lnow when I opened the cavity that there was only one wire coming in from each pickup, i dont know how their grounded as i didnt pull out one to check.
Rich

40

I’ve seen them grounded to foil or that conductive paint/goop.
I don’t like that, its the cheap-o way do to things.
You could run the wires that are probably grounded under the pickups back to the pots to eliminate any current or future issues.

I have a few J basses that they use the control plate as the ground connection between everything, don’t dig that either.

41

I guess I’ll need to pull the pickups and chech how their grounded, possibly foil cover the cavity at the same time.

Rich

42

Where do you normally fo your grounding, on the back of pot cases.
Rich

43

Wish i had a schematic of the original circuitry to look at.

Rich

44

Im not familiar with where the best ground places are truthfully.

Rich

45

I take the long capacitor ‘legs’ that get snipped off and run them through the pot ground connector and from pot to pot in a sort of ground bus.

46

Learning alot here.

Rich

1 Like