Help me find a good 25K or so Linear Taper Volume Pedal pot and Schem.

[aksman]

Please help me find a good 25k or so Linear Taper pot with the grooves fora wah/volume pedal. 

I gave up on my custom looper quest and found a good used G-system. I need expression pedals for it.  The best ones will be 25k Linear Taper. I'd like to find a good solid expression pedal with a good feel, and now.

Ideally, I'd like to just build a good crybaby/vox style one or do a replacement (with no on/off, just the taper pot) and a schem/pictorial instrucions would be greatly appreciated too (help with calibration also please).

Thanks guys.

[mr_fender]

Not sure of an off the shelf solution for that, since nearly all wah pots are log or modified log pots.  You can just use a regular long shaft linear pot.  Radio shack has the long shaft pots.  The wah pedal gears are available from Small Bear for a couple of bucks.  The pinion gear is the round one for the pot shaft.  The rack gear is the flat one attached to the wah treadle.  You'll have to cut the pot shaft to length and mount the gear, but it's pretty simple.  Keep in mind, though, dunlop/VOX style wah pedals can't rotate the pot the full 300 or so degrees, but usually only around 180 degrees.  You'll lose some range on the control, i.e. it won't go from full on to full off, but only a smaller range in between.  You can cut down the rubber bummers on the treadle and get a bit more travel, but not much.  It's just a physical limitation of this 40+ year old pedal design.

[mr_fender]

Oh, as for the schematic, none is needed.  Volume pedals are about as simple a circuit as you can get.  Using a linear pot makes it even easier since the orientation of the pot doesn't matter.  Just connect the "hot" wire of the input jack to one of the side lugs on the pot.  Next connect the "hot" wire of the output jack to the middle wiper lug on the pot.  Then connect the ground wire of both jacks to the other side lug on the pot.  That's it.  Since this is for an expression pedal, it may be easier to use a stereo jack, since most expression pedal jacks on effects use a stereo or TRS (Tip, Ring, Sleeve)jack and cable.  In that case, just connect the "tip" wire to one side of the pot, the "ring" to the wiper, and the "sleeve" to the other side of the pot.  Nothing to it.

[Barcode80]

and you'll probably want a cap across the outside to enhance treble that you will lose. probably would be a good idea to use a buffer. do a search in the gallery for buffer and you'll get some ideas

[aksman]

Hey guys,  I"m going to use it with a g-system.  It lets you set a minimum and maximum, so it won't matter if the pot is getting full travel or not.

SO, what pot can handle it?  and how do I get the Pinion to properly fit it???   

brands, resources, PLEASE?

[aron]

See if you can modify a cheaply available Bespeco volume pedal. I think it takes plain old regular shaft pots.

[aksman]

i'm using a Rocktron Hex.

I wanted to order the Piston from smallbear, which is a d-shaft one... but i'm not having much luck.

From the looks of things, the pot inside the Rocktron hex is actually just a regular ferruled Alpha brand pot (it says something like 25C25DK printed on it as well).  It looks like they just took that and threw a round piston on it and glued it in place.

[Processaurus]

Check this out: you don't need to order anything.  If it is indeed an alpha pot, and you have another linear taper alpha pot, you can swap the funny taper wafer for a linear taper one.  At Geofex.com there is an article called "the secret life of pots", it is all about what you can do when you don't have or can't get the right pot.  Swapping resistive wafers from one pot to another (almost always has to be the same manufacturer though) is one of the tricks in there.  I've done that also if it has a weird shaft that is hard to find.

Here's what I did to get a linear pot into a crybaby, it ended up being absurd, but sometimes you need linearity in your life.

[aron]

The Bespeco volume pedal costs less than $30 and I'm pretty sure can take a regular pot easily.