Problems with DPDT Tone Pot

[ThisGuyIsNew]

Hey, Hopefully, y'all can help me out with this.

Before: Silvertone Revolver Strat. Three single coils and 5 way box switch (Pics below)





Mod: I modded a strat to have a single coil sized rail humbucker in the Neck position (coil split), changed the tone controls to have a DPDT switch as the T1 pot (set for neck only), and switched the T2 pot to the middle and bridge pickups. Diagram below.



Status: I have all of the parts in and I get power through the system so that I can get a signal through the amp. Tests with a multimeter show that connections are working too.

Problem: See below
1.) The T1 pot works as a volume control. Trying to determine if it changes tone as well, but it can cut the entire signal when turned all the way down (main problem).
2.) Coil split doesn't seem to work, I did a tap test with the humbucker and both coils make a sound.
3.) The system seams to be noisy too, but that could be expected from single coils.

Solution: I'm looking for a way to set up the tone pot so that it doens't effect the volume and can coil split properly. Can anyone give me any advice on how to fix this? Thank you in advance. This is the first project I've done so it looks rough

 

[devastone]

Re: Problems with DPDT Tone Pot

I don't have time to look at it closely right now, but you might check here - https://guitarelectronics.com/guitar-wiring-resources/

I think your problem may be that you have tied the 2 tone controls together and trying to just use 1 capacitor. Each tone control should have it's own cap and should only be tied together at ground. Also, it looks like you have a lot of solder on the pots, make sure you haven't tied anything together that shouldn't be with a solder blob.

 

[AlexR]

Re: Problems with DPDT Tone Pot

^ Fenders have 2 tone pots with 1 cap, so that should work as long as its been wired up right.

I do agree on the solder issue - OP, what wattage iron do you have?? You really need 50W+ to be able to solder onto backs of pots without the chance of damage. The back tone pot has a connection on the back which I'd put good odds on being cold.
I would be looking to get fresh components myself.....the vol pot at least is over soldered.
Strip the wires where they need to be and cut them so there is no excess bare.....or simply buy cloth push-back wire that can be pushed back to cover the bare rather than the bits of electricians tape that are doing very little.

 

[Artie]

Re: Problems with DPDT Tone Pot

Your diagram says its a .47 cap. That will cause that problem. You need .047uf. That zero is important.

 

[devastone]

Re: Problems with DPDT Tone Pot

Good catch Artie!

Thanks for the clarification Alex, I haven't wired a 2T strat in a long time.

 

[ThisGuyIsNew]

Re: Problems with DPDT Tone Pot

Thanks for taking a look, this will give me a good starting place for fixing it.

The cap is marked with 2A437K and it is the cap that came in the guitar. I just reused it and tried to wire it the way it was before.

I'm not entirely sure about the wattage for the soldering iron, but I think it is a 60W iron. I probably had the temperature too high when putting the solder on. I was having issues getting it off and getting it to melt so may I'll try a much lower temp. I had it up around 400 celsius I think.

Yeah the solder job isn't great, I think I'm gonna pull it all off and start over if I can.

Thanks for the help, any help I can get is appreciated.

 

[devastone]

Re: Problems with DPDT Tone Pot

At a quick glance, the tone pots look okay, the terminals on the volume pot seem to have way too much solder on them.

 

[AlexR]

Re: Problems with DPDT Tone Pot

Thanks for taking a look, this will give me a good starting place for fixing it.

The cap is marked with 2A437K and it is the cap that came in the guitar. I just reused it and tried to wire it the way it was before.

I'm not entirely sure about the wattage for the soldering iron, but I think it is a 60W iron. I probably had the temperature too high when putting the solder on. I was having issues getting it off and getting it to melt so may I'll try a much lower temp. I had it up around 400 celsius I think.

.

This usually indicates too cool. Too hot never causes issue with melting.

 

[ThisGuyIsNew]

Re: Problems with DPDT Tone Pot

Hey, Thanks for your help guys. I finnaly got the chance to go back and work on some of these issues. I took all the ground wires off and some of the hot wires, and resoldered them in. I wasn;t able to get the heat shrink tubing yet so I had to make do with some tape again. The only wire that I have not connected yet is the bridge ground, which you can see sticking out in some of the pictures.

The problem that I am having now is that the coil split isn't working the way I wanted it to. I plugged it into the amp and did a tap test using a guitar patch cable (first thing that I could find that wasn't magnetic). There is a lot of white noise, but that could be expected from the open ground cable. The volume knob works well across all of the pickups. on the humbucker, the first rail seems to have a much thinner sound than the second rail. It is wired to the first tone knob where the push/pull pot is. The tone spot still seems to kill the volume, although it may be reducing the tone as well (its hard to tell without the strings on). In the up position, nothing changes, the tap test shows that both rails are till on. I'm not sure what to do here since it just isn't turning off. I also noticed today that the push/pull knob only clicks going to the down position. I don't remember if it ever clicked going up, but it doesn't now. The other tone pot seems to be working fine as far as I can tell. I also put on a new capacitor that I just got yesterday.

I'm at a loss for what to do with this, so any help is greatly appreciated. Pictures attached.

 

[ThisGuyIsNew]

Re: Problems with DPDT Tone Pot

Update: So I may have found the solution aside from the fact that the pot is still probably a little broken. The seymor duncan diagrams don't say which side is up on the pot terminals, so I think I attached the ground to the wrong terminal. I moved it to terminals A and D (top two when the pot is pointing up) instead of the bottom two. I also noticed that the tone capacitor may be attached wrong. I looked at the original pic that I took and it should not be in between the pots (each leg is touching a different pot instead of both on one with a wire connecting the two). I'm gonna try moving it and see what happens.