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Multimeter shows pots resistance instead of pickup resistance when conn to jack

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Rango:
Thank you so much. Ok i have done complete rewire. I think problem was on switch i had positive soldered onto negative and negative soldered onto positive. Anyhow i can now measure pickups at jack of the guitar. Also one of the grounds copper wire had poor connection or cold solder. I also fixed that.

However there is something odd here. When pots are at max volume 10 it registers 8.4k in neck and 14.4k in bridge, however when i turn pots down to middle it will actually show weird value like 40k ohms, and even something like 132k ohms. The middle when both pickups are on it reads at max volumes of both pots 5.0k ohms.

I'm pretty sure that's not normal unless 50s wiring and .022pf cap is doing this. I don't know what to make of that. I will post pics shortly. I'm tired troubleshooting this. I've been at it for 2 full days lol

Also i've done continuity on that ground wire and you ware correct it's connected to bottom log of tailpiece. For now i've tape it off with electrical tape as i'm not trusting it yet.

alsetalokin4017:

--- Quote from: Rango on October 23, 2019, 01:33:57 am ---Thank you so much. Ok i have done complete rewire. I think problem was on switch i had positive soldered onto negative and negative soldered onto positive. Anyhow i can now measure pickups at jack of the guitar. Also one of the grounds copper wire had poor connection or cold solder. I also fixed that.

However there is something odd here. When pots are at max volume 10 it registers 8.4k in neck and 14.4k in bridge, however when i turn pots down to middle it will actually show weird value like 40k ohms, and even something like 132k ohms. The middle when both pickups are on it reads at max volumes of both pots 5.0k ohms.
--- End quote ---
Actually that sounds pretty normal. In the middle you are getting a combination of the pickup and the pot resistance, the proportion of one going up and the other going down as you turn the knob. Your values are similar to what I just measured on my Ibanez.

--- Quote ---
I'm pretty sure that's not normal unless 50s wiring and .022pf cap is doing this. I don't know what to make of that. I will post pics shortly. I'm tired troubleshooting this. I've been at it for 2 full days lol

--- End quote ---
It's normal. I think you have got it hooked up like you want it now. 

--- Quote ---Also i've done continuity on that ground wire and you ware correct it's connected to bottom log of tailpiece. For now i've tape it off with electrical tape as i'm not trusting it yet.

--- End quote ---

I trust it. Just go ahead and solder it onto one of the pot bodies or another convenient ground point. This assures that the tailpiece, bridge, strings and headstock tuners are all grounded (connected by the strings themselves.)

Now string it up and see if it all works!

alsetalokin4017:
Ah... you don't have a guitar amp yet do you. Guitars can sound funny/weird/broken when amped through other kinds of amps, due to the weird impedance mismatch. So you really won't be able to tell how it sounds and if it is 100 percent working until you can try it with an actual guitar amplifier.

Rango:

--- Quote from: alsetalokin4017 on October 23, 2019, 04:47:42 am ---Ah... you don't have a guitar amp yet do you. Guitars can sound funny/weird/broken when amped through other kinds of amps, due to the weird impedance mismatch. So you really won't be able to tell how it sounds and if it is 100 percent working until you can try it with an actual guitar amplifier.

--- End quote ---

Many many thanks to you and all that helped me. I will ground that wire too. Didn't know you need to ground the outside of it too. Will do.

Luther will need to install the nut and do full setup, as i took old plastic one out as guitar would not stay in tune. Got the Tusq nut, locking grover tuners and rolling bridge as well. That should do it.

If the old nut would not be cut on weird angle i would do it myself but i don't want make things worst by filing. I'm thinking of Boss Katana 50 as it's fairly cheap but may try Amplitube 4 with audio interface first as those i have already.

alsetalokin4017:
Yep, changing out the plastic nut, (and saddle on acoustic guitars) is probably the single most cost-effective thing you can do to a guitar to make it sound better and be more playable. I put buffalo bone nuts and compensated saddles on acoustics and it is amazing how much better they sound than with the old plastic bits. If you are a real note-bender, the rolling bridge, and the Tusq nut will help for sure.  Personally I think locking tuners are a step too far, like belt plus suspenders, but yes, good high-ratio Grovers are da kine.

Just one more thing to check: the Tone controls should not affect the resistance readings at the Jack at all. The tone capacitors function by sending high frequencies to ground, removing them from the signal, and the tone pots control how much. Capacitors don't pass DC current, and the multimeter is using DC current to measure resistances, so the caps look like open circuits no matter where the tone pots are adjusted. Neat!

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