Rewiring gone wrong - possible pot issue?

[axandria]

Hello everyone.

I wanted to rewire my 2019 Indonesian Squier Strat HSS from having standard 1 vol 2 tone to having 1 vol 1 tone with no auto coil split (as my humbucker doesn't have the needed wire).

I used this schematic:

I can't get the pickups to produce a sound. There is an ambient hum and then a buzz when touching the hot wire of the jack and the pin it's soldered to, but no signal beyond that. Turning volume knob has no effect on volume of that buzz. For both tone and volume I used B500k pots. Previously this guitar had 3 A250k pots. Here are wiring pics. How do I get it to produce a sound?
Pics:

[unreg]

hi axandria! Welcome to GNuts2!

I’m replying just to say:

1.) perhaps your soldering on your jack’s hot lug needs to be fixed.

2.) your images that show up on are low resolution, so it seems, even after zoom in, like you have a giant blob of solder on top of your volume potentiometer. It is possible that you’ve killed that vol pot with too much heat. Pots now are often made with cheap materials and so frying them with lots of heat from a soldering iron is really possible.

A cool alternate grounding method is a star ground. When a star ground is used your pot cases could really possibly be solder free… and so free of possible heat damage.

3.) B500K, as well as B250K, pots are linear taper; while A250K, as well as A500K, pots are logarithmic taper. The human ear responds to sound in a logarithmic manner. So, turning an A volume pot half way up will cause your ears to hear the sound at 50%. B volume pots produce sound changes in an alternate manner. Maybe you already know this. If so, sry.

[newey]

axandria-

The diagram is fine. The difference in pot values would not cause it to have no output at all. So, you're dealing with a wiring problem, not a design problem. unreg is right, possible that you fried a pot, but let's hold off on that for now.

It is very difficult to do troubleshooting over the web. Photos can help, but usually don't, since if there's a bad connection it probably won't be obvious from a photo. It is a lot easier to diagnose a problem if one of us could actually have the guitar in our hands, but we can't. But we'll try to help as best we can.

A couple of ideas to try first. If there is no output at all, that means the problem isn't the wiring from one or the other of the pickups to the 5-way switch, the problem must lie "downstream" of the switch. Best to start at the jack and work backwards. First, check that you did not accidentally swap the + and - connections at the jack. This is an easy mistake to make, I've done it myself a few times.

If the jack is connected correctly, gently tug a little at each of the jack wires, and the wires to/from the volume pot. This may disclose a bad connection. Lastly, hit the solder connections to the pots and jack, and from the 5-way to the V pot with your soldering iron briefly again, just enough to remelt the solder. This sometimes is an easy fix for a bad connection.

If none of that works, report back and we'll dig further. More detailed troubleshooting will require the use of a multimeter. Do you have one, or have access to one?

[axandria]

newey
Thanks for suggestions!

I've soldered the bare wire of the jack to the back of the pot, and the hot (white) wire to the middle lug of the volume pot. If I touch the exposed wiring of the hot wire or the middle jug with metal object, I get a buzz coming from amp. I don't get any sounds if I touch the volume pot, any other wires connected to it. No sound comes from tugging any of the wires.

Here's the video (I hope it's OK to post a YouTube link here. Apologies for messy table):

I've tried melting jack and 5 way connections to the vol pot, but it didn't do anything. 

For some reason my jack also has an additional wire, which seems to be connected to ground pin of the jack. On Reddit I was told this black wire is rudimental and can be ignored 

I do have an access to multimeter, but it's a cheap model I got with the soldering kit a while ago. Should get the job done though. 

I managed to source some A500k pots with properly shaped lugs. I will use them if these B pots turn out to be fried.

[axandria]

unreg

I've tried to look up the star method of grounding, but it just pointed me to the standard method of soldering all ground wires to one point on the volume knob. Could you please elaborate?

[newey]

What he means by "star grounding" is to use one central point where all grounds are collected, ansd wired from there to the jack -. This avoids difficulties with soldering to the back of the pots. Usually this is done by using a washer, to which one solders all the grounds, and then the washer is screwed into the side of the control cavity so it contacts the cavity shileding, assuming the cavity is shielded. There are other ways to do this as well.

No sound comes from tugging any of the wires.

I didn't expect you would get a sound, I thought it might show a loose connection.

The jack looks to be wired correctly. You are using a shielded cable for the output wiring (which is fine to do); the bare wire is the ground wire, the white center core is the hot from the V pot. And again, all that looke OK. You don't need the black wire, that is also grounded and is superfluous. It can be removed, but that shouldn't be your issue.

Using your meter set to resistance ("Ω"), you will check for continuity between the far end of each ground wire and the pot shell to which it is soldered. Some meters have a "beep" setting for continuity, but a good connection should show virtually zero resistance, a few Ohms at most. If it is infinite (or "out of range" on many meters), there is no connection. Then do likewise between the wire from the center lugs of the 5-way (the one going to the volume pot, check it at the switch end) and the tip of the jack.

[sumgai]

axandria,


Hi, and to The NutzHouse!


Number 1: I can't be 100% certain, given that your latest photo is only 2D, but it sure looks to me like the black and white wires on that jack are touching each other, thanks to the partially stripped insulation on the white wire. (About one-half inch back from the jack.) But the fact is, when you assemble that jack-and-plate back into the guitar body, there's a pretty good chance that the wires just might end up twisting around and touching each other. Try putting some electrician's tape over that bare spot on the white wire, and then test again.

Number 2: The 5-way switch has 8 lugs, whereby the center two terminals are soldered together, and a wire runs from there to the Vol pot. So far so good, but on the 'other' side of that switch is a connection to ground, seen in both the diagram and the photos. How is this not going to kill the signal for positions 2 thru 5? Break that connect between terminals 4 and 5, and see what happens.....

HTH




sumgai

[axandria]

@newly

I've put multimeter at 2000k ohm setting to measure this.

I assume that by the "far end of the wire" you meant the end that gets soldered to the pot. In that case, all ground wires soldered to the pot shell show 0 Ohms.

Measuring between the center jug of the 5 way switch (aka where the red wire is connected to the volume pot) and the metal plate of input jack gives what I assume is 10 Ohms ("010" on the display).

Measuring between a tip of inserted cable and the center jug of 5 way switch shows no continuity. The cable itself works fine and shouldn't be an issue.

If I measure between the tip of inserted cable and the jack hot wire connection, there IS continiuity. But if I measure between cable and anything past that point into the rest of the chain - I get nothing. Strange.

[unreg]

Sept 10, 2024 6:51:46 GMT -5 axandria said:

unreg

I've tried to look up the star method of grounding, but it just pointed me to the standard method of soldering all ground wires to one point on the volume knob. Could you please elaborate?

Yes, though newey already elaborated.

In the past I’ve read brains here, maybe ashcatlt, say something about ground is a destination; ground isn’t a signal. And so therefore it’s possible to move grounding connections away from the pot cases. Newey said a washer is usually used, but the star ground can really be any conductive piece; such as a (newey’s idea) paperclip. So, I used a straightened-by-my-fingers paperclip. My paper clip did have continuity from one end to its other; very important! My control cavity contains my starground; AND it was painted 4 times with a conductive shielding paint, cause I’m a low quality shield painter. Therefore, I just made a small loop at the end of my paperclip, with a round metal screwdriver shaft, and then attached my paperclip to a cavity wall using a small metal screw through that created loop. Next, I first trimmed (don’t trim too much off) and then bent the paperclip along my painted cavity wall so it matched the wall’s curves. Then, all the ground wires were disconnected (including the MOST IMPORTANT jack ground wire) and routed to that paperclip; that OR I added new appropriate length wires to star ground items such as capacitors. After all this, I unscrewed the paperclip from the cavity wall; so, that all soldering to my starground paperclip could be done outside of the cavity; I found that much easier! Finally, after soldering was done, I checked continuity from an exposed piece of each wire soldered to that paperclip to jack’s ground lug, that lug or the ground sleeve of a connected guitar cable. I attached my paperclip back on the cavity wall with that screw, then later added new pots. It works wonderfully!

The pot shells are supposed to be grounded via the cavity shield ground, but I added a grounding wire to my pot shells… that meant 1 tiny solder spot on each pot shell… and that ground wire was connected to my star ground; good that I didn’t trim that paperclip too short.


EDIT: And that paperclip was covered as much as possible, lots of wires in the way, with electrical tape.

[unreg]

Sept 10, 2024 11:10:46 GMT -5 axandria said:

If I measure between the tip of inserted cable and the jack hot wire connection, there IS continiuity. But if I measure between cable and anything past that point into the rest of the chain - I get nothing. Strange.

There is a faint possibility that this happened to me too AND was fixed after I was told to test the jack’s ground connection for continuity. It was broken, I fixed that, and I had sound again; you might try that.

[axandria]

A quick update: it seems like the issue was in a fried (or just bad quality) potentiometer after all.

I've desoldered both pots, replaced them with a higher quality full sized A500k pots, put the chain back together (this time being careful with the temperature when soldering to pots) and it works now. Thank you all for the advice! I've learned quite a bit about soldering and inner workings of guitar doing this.

[sumgai]

Sept 11, 2024 11:44:44 GMT -5 axandria said:

and it works now.

Am I the only one who sees a problem with the way the 5-way switch is wired?







sumgai

[frets]

It doesn’t look like the ground on the switch is actually attached to a lug. On the diagram, it looks like it is attached to the case of the switch. At least that’s the way it looks to me (zooming in on the diagram).

[sumgai]

frets,


Yes, if one zooms in about 1000%, it becomes a bit more obvious that you're correct. Looking at the images themselves, and zooming in, it's also obvious what's going on.

And thus, we see the dangers of using pictorial diagrams (which was what was actually posted by axandria) instead of schematics, but he/she didn't know the difference, so I can't flog him/her for that one.

I must be getting old.....






sumgai

[ashcatlt]

Sept 10, 2024 19:07:22 GMT -5 unreg said:

In the past I’ve read brains here, maybe ashcatlt, say something about ground is a destination; ground isn’t a signal.

I’m pretty sure I never said any such thing, but don’t really want to get into a whole thing about it right now. I personally try to collect grounds at actual solder lugs whenever possible. If I have a pot or switch chassis that can’t get to ground any other way, I might solder a wire to one of the washers I’m going to use in mounting that component. In this case, I think the pot cases would find their way to ground via the switch’s frame ground (that lug sumgai was worried about).

I’m not convinced the pot was borked (did we ever measure it?), but am not surprised that resoldering the whole mess made it work.