Lovepedal Believe Trimpot Issue

[JVO]

I bought a Lovepedal Believe which intermittently cuts out and is inconsistent in output. Because the trimpots are internal, I have to take the backplate off in order to readjust it. When I do, I believe the volume trimpot is faulty because it is inconsistent and cuts in and out.

The trimpot measures at 22.35KΩ to 40Ω. It has no markings on it which gives insight as to whether it is linear, audio, or reverse audio. It is a CTS trimpot.  I emailed love pedal but I think they are out of the game so no response. No schematic on this pedal floating around, either.

The trimpot is labeled TR2 on the board.



I desoldered it in order make sure the values were correct and to try to look for markings that could give a clue.





Here's my question: what is the name for this type of trimpot? It's the kind where there's a hole on the pcb in order to adjust it from the other side. Any way I can determine if it is an audio or linear? When I try to find trimpots, I find other form factors but not this one. Any ideas on how to fix this?

Thank you in advance!

[idy]

Almost certainly linear. Trimpots are. Other tapers make knob twisting feel better to humans. Trimpots are set with screw drivers....once.

To check taper: You turn clockwise. measure the resistance center to "left" (pin 1). Lets say its 20k. You turn half way and measure again. If it says 10K, probably linear ( possible w or s taper..) If it says something else, like 2k or 18k, you have *some other taper" like log or reverse. If you are really curious you make a little graph and write each of a dozen or so spots on the dial.

There are 22k trimpots. I don't think there are audio taper trimmers.

[JVO]

Thank you for the response!

Is there a search term I should be using when trying to find a replacement? When looking for "through-hole trimpot", I get something that can be soldiers onto a board but looks like this:



or



When looking for "horizontal CTS trimpot", I get close but these are in MXR pedals too so it's not like it's bespoke or anything.

Any help would be appreciated.

[JVO]

Actually, I found this very helpful page just now: http://www.partscaster.net/?tag=lovepedal

It appears to be a 25k linear trimpot. I'll see if I can track one down.

[idy]

The Brand looks like Amphenol. You can use any brand,  many allow adjustment from both sides of the board. Common failure, as pushing through the board with the screw driver stresses the pot.

If you are really curious go to mouser.com. Search trim pot. You will see "all" the trimmers in the world. Use the search filters. Maybe not the best place for small order, but you get to see the "universe." And download data sheets for likely suspects. 22k, 25k, value "probably" not critical. And pots have wide tolerances anyway.

But you would probably be happier doing like on the page you found. Knobs, knobs knobs.

[JVO]

Thanks for the help!

The part is 262UR253B and it is no longer made or available from Mouser.

When I go to mouser and try to find something similar, I get these results: https://www.mouser.com/Search/Refine?FS=TRUE&N=16330853+4292986627+4294437873+4292859812+4292098659+4292724556+4247544734+4292906361 which aren't close to the same form factor. Am I looking with the wrong filters?

Thank you in advance.

[Govmnt_Lacky]

There is this alternative from Bourns:

https://www.mouser.com/ProductDetail/Bourns/3306F-1-253/?qs=%2Fha2pyFaduhVnqGF2AazlbLUjGBpVsQ452Wj20mcLb8%3D

Not 100% sure if it is adjustable from BOTH sides though 

Do you have room in the box to mount it on the side of the board where you can get to it for adjustments?

[JVO]

Yeah, I think I could fit it in there but I'd be a little worried about stressing joints if I had to cram it in. Another option is doing like what the link above did where they just added an alpha pot to the case. I don't think it was a wise idea to have something like volume be a trim pot. I know that this thing was supposed to be set it and forget it but, sheesh.

Looking at my MXR pcb, it has a piher trimpot so now I'm trying to track down something that has the same pcb footprint as this does.

Thank you for all of the help!

[JVO]

It looks like musikding.de has what I need: https://www.musikding.de/Trim-Pot-10mm-25k and here's the spec sheet: https://www.piher.net/pdf/12-PT10v03.pdf