A Quandary

[frets]

Hi Guys😸😸😸,

I’ve got another weird problem that has me stymied. I built a regular Strat harness for a guy and sent it to him out of state. He put it in his guitar and has a problem with it. In the middle 3 positions, the bottom tone pot cuts out the signal when rolled to 10. Less than 10 and the signal comes back. What in the heck could cause something like that? As usual, thanks😺!

[Deleted]

With it being Tone
It's ever Grounding the Hot signal
Or the Hot and Ground have come Equal

Does seem strange just to be in Middle position only

[sumgai]

Jun 25, 2022 17:09:48 GMT -5 frets said:

What in the heck could cause something like that?

The only two possibilities are:

1) Physical damage to the pot (shipping, carelessness, etc.);
2) Solder glob placed where it shouldn't be placed (and thus creating an unwanted "solder bridge").

Of course, I'm eliminating the possibility of the pot being defective pot from the get-go, because you test everything you build before sending it out the door.

But for the rest of you readers..... seriously, test each and every component before you install it. A larger-the-you'd-guess percentage of all the questions we get here in The NutzHouse are found to be caused by parts that were defective before they ever darkened your doorway.  Others here will chime in and second this notion.

And here's a pro tip: take notes while testing. When the stinky-stuff hits the rotating ventilation device, your notebook will give you a pretty good idea about where to start looking for the problem(s).

Another stress-busting tip: document your entire project from the time you buy your parts to the time you hit "STOP" on your camera as you finish recording your latest-and-greatest invention for YouTube. Text, photos, drawings, sound clips, they're all fair game for your notebook.

Do these three things religiously, and I guarantee that you'll be thanking me at some point down the road.

HTH




sumgai

[MattB]

Some questions that might help:

1) Does the sound fade in gradually, or turn on suddenly?

2) Exactly where on the pot does this happen?

3) No-load or regular pot?

4)What do the middle positions sound like with the tone pot at 0? Does the tone change as the pot is rotated?

5)What connections was the customer required to make?

EDIT:

6)Does the tone pot work correctly in position 1?

( I assumed that "regular Strat harness" meant one tone for the neck pickup, and one tone for the middle and bridge pickups. If the second tone is only for the middle pickup then the most obvious possibility would be the unused lug of the tone pot being connected to ground somehow.)

[newey]

Jun 25, 2022 20:29:48 GMT -5 MattB said:

I assumed that "regular Strat harness" meant one tone for the neck pickup, and one tone for the middle and bridge pickups.

If by "regular", we mean the way Fender made 'em (and still does, at least in the classic versions), one tone pot is for the neck and the other for the middle only. There is no bridge tone control. Thus, having an issue in positions 2, 3 and 4 makes perfect sense if the middle tone pot is the culprit.

The classic Strat set-up thus has both pots active at position 4 (N + M), where the two will interact with each other. That interaction led to one of the early Strat mods, moving the middle tone pot to the bridge instead. This gives a bridge tone, which many find more useful than the middle, and avoids the interaction at position 4.

[frets]

Guys,
I just made him another and sent it to him. It’s such a simple harness and I lost about $20 on the deal.

I will say that in this last batch of CTS pots, I’ve got three bad pots out of 50. If his pot is bad, that makes 4. Not good at all. I would use Bourns pot because I can get them for a dollar fifty less per pot, but guys want CTS. Overall, CTS has exemplary quality, I just must have had the coincidence of a few bad eggs in the batch. I measure every one I use. The 3 bad pots had resistances of 80, 130 something and 190 something. I just got this batch. I hope there are no other bad ones. They cost me $4 each!!

Anyway, thanks to you who tried and help me with this “quandary”.

It’s been my month of problems. I have another weird one I will probably be posting.

[Deleted]

I never think about testing pots before I use them. I'd expect them to check out.
8% fail rate isn't good at all

[newey]

Or are they perhaps Chinese knock-offs that someone is stamping "CTS" onto?

I'm no cynical1, but if it was ordered through a Chinese vendor, I might be suspicious.

Not sayin', ya know, just sayin . . '

[frets]

No, they’re real. They’re from CDE Distributing. I have written the company to complain. Whine

[cynical1]

Jun 27, 2022 19:53:59 GMT -5 newey said:

...

I'm no cynical1...

And I lack the testicular veracity to walk out in the snow wearing just my bathing suit...with or without an instrument...

That said, back in the 70's everyone wanted a brass nut on their bass. The theory was sound...no pun intended...but after they played it a while and found it sort of sucked...I got repeat business later by removing it... I found myself eventually warning customers off of the process. If you provide a product or service it's almost incumbent on you to caution customers about certain "fables" they refer to when buying gear...

It's like horse training...make the right thing easy and the wrong thing difficult and the horse will always choose the right thing. Guitar players are just a bit harder to train as it takes more repetitions...

First, some neglected customer service training:



If the traffic insists on CTS pots, then allow for the additional QC in their cost. Based on your recent experience with your pots through your current vendor, you lose 6% off the top. You also have the time spent testing the new inventory and the cost of equipment to do so. What have you really saved here and are you servicing the customer?  Remember, they want what they want...not what they asked for.  They'll come back for your expertise, or they'll buy it elsewhere cheap online.  Either way, the quality of your customer base goes up...

My long dead economics teacher called it the Opportunity Cost...at the shop we just called it an Aggravation Fee. Either way, you can have the design with proven components for this cost...or you can have the custom CTS version with all of the additional costs and frustrations built in. That way, if it fails in the wild, you've already recovered your costs on replacement.

Happy Trails -

Cynical1