mod wheel fix

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voyager0500
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Re: mod wheel fix

Post by voyager0500 » Fri Mar 29, 2013 5:51 pm

Hi guys,

I would also like to know if the mod pot is replaceable because on my Electric Blue when a function is modulated by the mod wheel it scratches just above 0 and its getting really annoying.

I started considering to get the after-touch mod for the sake of the mod and to get rid of the scratching caused by the faulty pot.
'i used to be a plastic cup..'
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CZ Rider
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Re: mod wheel fix

Post by CZ Rider » Sat Mar 30, 2013 2:46 pm

voyager0500 wrote: I would also like to know if the mod pot is replaceable.
Depends on your skills. If you are able to solder and re-assemble the wheel mechanism, should be no problem. For a drop in solution, the upgraded aftertouch would be the way to go. Moog music seems to believe this is the solution, as the aftertouch upgrade is a simple circuitboard swap. But they only seem to offer the whole assembly that is a very expensive upgrade giving you a new complete assembly.
Those Bourns pots should be easy to source, 10K linear. Think I found them listed at around 10 bucks. They look like this:
Image

I was able to upgrade to beefier AB type pots but ran into all kinds of clearance issues. So I would recommend replacing with the original Bourns type pots.
I had a different problem with my pitch wheel not returning to center. Especially noticable if I set the wheel to any interval a fifth or over. My pitch wheel would throw the Voyager and any MIDI connected synth out of tune. Bad, really bad! This issue I am finding has more to do with the return spring on the clear plexi wheel machanism. The plastic molded set has a different stop, and seems much better at returning to the same spot. Here are the two different wheels.
Image
After doing some measurements, it was easy to see why the clear wheels did not always return to the same resistance. There is too much play in the return mechanism on those clear wheels. Even after replacing the pots with new ones, I still got readings that would not center with any repeated accuracy. While the molded wheels were spot on.
Image

So I'm just going to use the molded ones. Always thought the lighted wheels were kind of cheesy anyway. But I was able to fit the AB type in the mechanism. Very tight fit with the clear wheels. Had to first alter the bracket and enlongate the mounting hole and drill a new locater hole so the new pot would not slide.
Image
The clearance on the clear wheels was too tight with the lock washers on the screws that held a plate on top for the spring stops. So I had remove the lockwashers and it cleared. This is where the clear wheels and the molded one differ. The molded ones have the stops molded in, so no screws or lockwashers used on them. Plus there is a hard surface on the molded wheel. The clear wheel uses some kind of taped covering that wears out over time. Can see the screws touching the top with the lockwashers in place.
Image
I was able to mount the AB's in there but the clearance due to the width of the back of the pot limited any adjustments.
Image
From the top you can see they just fit. The molded wheels are thinner and this is not an issue with them.
Image
So in the end I found the problem I had was more to do with the clear wheels centering, then it was the actual pots being the reason. The new AB pots do feel more solid, and do not have as much side to side play as the Bourns do. But I don't recommend it as a suitable replacment, especially with those clear wheels.
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voyager0500
Posts: 56
Joined: Fri Nov 10, 2006 4:56 am
Location: London
Contact:

Re: mod wheel fix

Post by voyager0500 » Fri Apr 05, 2013 4:40 pm

CZ Rider wrote:
voyager0500 wrote: I would also like to know if the mod pot is replaceable.
Depends on your skills. If you are able to solder and re-assemble the wheel mechanism, should be no problem. For a drop in solution, the upgraded aftertouch would be the way to go. Moog music seems to believe this is the solution, as the aftertouch upgrade is a simple circuitboard swap. But they only seem to offer the whole assembly that is a very expensive upgrade giving you a new complete assembly.
Those Bourns pots should be easy to source, 10K linear. Think I found them listed at around 10 bucks. They look like this:
Image
.
Hey CZ Rider!

First of all thank you for the detailed explanation of the issue along with the pictures that you attached.

Do you have the Voyager After Pressure upgrade on yours? How much of an improvement is it compared to the old one do you know?
As of now I dont really use the after touch on my EB simply because it acts as a on/off control atm.

It surely is on my list of "to get" things but it is not a priority since im in the UK and dont think anyone stocks the parts over here.

Check this out: http://uk.mouser.com/ProductDetail/Bour ... Bh0jm4Mw==

This seems like the pot I need for the MOD wheel. They are less than £2 so no wonder the quality is crap. If I had the upgraded LH component I might go through the trouble of replacing the Bourns pots but since its the old type Im not going to bother.

Having said that I really need to replace the MOD pot as its affecting the wheel a lot in the lower range. This only becomes even more evident when the wheel CV is sent through the mult.

Thanks again!
'i used to be a plastic cup..'
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CZ Rider
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Re: mod wheel fix

Post by CZ Rider » Fri Apr 05, 2013 11:32 pm

voyager0500 wrote:
Do you have the Voyager After Pressure upgrade on yours? How much of an improvement is it compared to the old one do you know?
As of now I dont really use the after touch on my EB simply because it acts as a on/off control atm.

It surely is on my list of "to get" things but it is not a priority since im in the UK and dont think anyone stocks the parts over here.

Check this out: http://uk.mouser.com/ProductDetail/Bour ... Bh0jm4Mw==
I have the aftertouch upgrade. Works great and it was just on/off before the upgrade. I did find it more usefull though by using the VX-351 and routing the CV via the attenuator, to adjust the ammount of aftertouch CV. For stuff like a bit of extra filter cutoff from aftertouch, it seem easier to dial in the ammount I wanted via the VX-351.
I did not order a Bourns replacement from Mouser, but the one you listed does not look like the correct one. The original part number comes up obsolete, #3852A-282-103A. Mouser has listed a #3852A-282-103AL? Not sure what the L is for, but here is a Mouser UK link to what looks to be the newer part.
http://uk.mouser.com/ProductDetail/Bour ... YwFcWEg%3d
A little more expensive at £7.23, but looks to be the proper replacement. Might want to ask Moog's service if that is the correct part before ordering.
The aftertouch upgrade is a full set of wheels, so that would be another way to go.
Last edited by CZ Rider on Fri Apr 05, 2013 11:41 pm, edited 1 time in total.
1P Modular,Minimoog,VoyagerRME,CustomMinimoog,Prodigy,MG-1 TaurusII,Opus3,Rogue,Source,Liberation,Micromoog,1125S&H,
1130Perc.x2,1150Ribbonx2,Custom1150,1120Pedal,Songprod,CP-251,VX-351
VX-352,Etherwave,Synampx2,Lil'Phatty,Sonic Six

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