Are there places that can repair a trim pot?

[skiraly017]

I have a Dearmond Pedal Phaser that has a trim pot that's shot. I have not been able to find a direct replacement for it and since the pedal is all original I'd prefer not to monkey rig something in there. Are there places that rebuild or recondition? The trimmer looks like the one in the picture. Thanks.

[Mark Hammer]

Whenever folks diddle with the components in a vintage amp, and worry about the resale value, the typical recommendation is to replace those parts that need changing with new components so that it works right, and save the old parts in a bag for whomever might one day buy the amp, and let THEM decide whether to re-install the original parts.  I think the same advice applies here.

Given that trimpots are not supposed to encounter heavy use (i.e., they are supposed to live a set-and-forget life, not the exahsuting life of a wah pot), it seems unlikely that the resistive strip is worn down.  So either it only needs a decent cleaning, or else the chassis has been misshapen by heat or whatever over time and the wiper is not making decent contact (in which case it needs replacing).

[skiraly017]

The pedal was sold as not working. When I got it I noticed the top of the battery had either rotted or exploded and it destroyed the battery clip. Once I replaced that the phase seemed weak so I went to adjust the trimmer and the resistive strip cracked into pieces and fell apart. I have no problem replacing the trimmer with a new one but have been unable to find one that matches the footprint of the existing one which is why I was looking at options.

[yodude]

How about using a little daughter board?

[skiraly017]

How about using a little daughter board?

An option, but as I stated in my original post I'd prefer not to rig something up if I don't have to.

[Mark Hammer]

There are a LOT of different trimpot footprints available.  When I look in my parts bin at the various trimpots I have, there are at least 30 different footprints.  I'm not questioning the breadth of your search, but the universe of trimpots is bigger than a scour of Mouser, Digikey, and Small Bear would suggest.  There are also all those surplus sources for "vintage footprints".  Maybe if you gave us some specs or a pic, someone might be able to direct you to a suitable replacement.

[skiraly017]

Hey Mark...the trimmer need is the same one in the picture. I did check Mouser but no matches. I'll pull it this weekend and do pics and dimensions. Thanks.

[Mark Hammer]

Sadly, I can't see any pictures.  They block links to image archive sites here at work. 

[skiraly017]

Sadly, I can't see any pictures.  They block links to image archive sites here at work. 

I'd be hosed if my company started blocking stuff. 

[Mark Hammer]

I can actually see a fair amount, but they block the most popular sites like photobucket.

[axg20202]

By the sounds of it, it definitely needs replacing. Have you desoldered and removed the dead trimmer yet and do you know what value trimmer it is? If you can provide some details of the pin spacings as a triangle, with measurements for each 'side', I may have one that will do the job, but I need to know the R value too.

[Mark Hammer]

Here is a dumb question that should have been asked already:  Is thetrimpot in question used as a voltage divider or simply as a variable resistor?  If the pedal is only using it as a variable resistor (e.g., many phasers use a trimpot as variable resistor to set the maximum resonance before the circuit breaks out into oscillation), then all you really need to do is temporarily wire up a pot, identify the critical resistance, and solder a suitable fixed resistor to the two trimpot pads in question.

[axg20202]

*slaps forehead* Of course!

Although if the trimmer is the 'mix' trimmer between the dry and the phased signals, the OP could be out of luck and back to plan A. Although I guess you could still work out the optimum mix (resistance on each side of the pot) using this method and sub in two fixed resistors. Or....I could be talking through my hat....

[$uperpuma]

Skiraly, if you can get a closer pic and a value, I'll check in my stash of old trimpots.. I probably have 3 pounds of them in all shapes and sizes... its a long shot but if I can help, I'd like to.

[skiraly017]

Hey guys...detailed pics and measurements will go up this weekend. There are a lot of ways I can fix this. The truth is the pedal was hard to find and I would like to keep it stock looking. This is just me being a little anal retentive about it. 

[axg20202]

Fair enough. Once we have the measurements and specs I'm sure one of us will be able to find a suitable trimmer....