Neovibe Pot Range and Sweep Depth

[Stratomaster]

Hello,

I'm finally getting around to polishing my Neovibe off for mounting on my board.  It's been quite an ordeal.  I have mine mounted in an unusual wah chassis, and it has limited sweep ability.  I can only get maybe 1/4 rotation from full heel to toe travel.  Is it possible, by maybe using tapering resistors, to compress the speed range down to this travel?  If so, that'd be awesome.

Also, I've heard about ways to make the vibe effect more intense, but have not been able to find specifics.  I already installed the mix trimpot to get the proper wet/dry ratio.  But I haven't done anything else.  What else can be done to make the effect more pronounced?  Thanks!

-Omar

[Stratomaster]

No bites?  Oh well.

[Stratomaster]

I figure I'll give this one last try before I start saving up for an MDV-2...

Any suggestions?

Thanks.

[MicFarlow77]

Hey Omar,

A couple of questions:

The amount of travel you will get mechanically from the pot is a direct relationship to the amount of travel from the paddle.  Are there any options to increase that amount of travel? Would a longer rack that meshes with the pinion help you to get more travel mechanically?

If you need some rack that you can trim to fit, I'll be happy to work something out... I have a bit of it that I can part with easy enough...

Thanks,

Mick

[Stratomaster]

I really appreciate the offer, but I have an unusual wah pedal enclosure that I'm using for the Neovibe.  It uses a 2 bar linkage with a set-screw on the pot shaft to rotate it.  I can take the "heel" end of the rocker pedal to a belt sander and maybe coax out another 1/8"  rotation out of the travel, but I'm not entirely sure that will cover the entire the full travel I'm looking for.  Also, if it's just a matter of a few tapering resistors to accomplish this electronically, then that is much easier than risking irreversible damage to the enclosure.  No matter how much "rack" I have, it won't help this one particular application.  Thanks again.

-Omar

[Eb7+9]

if you look at my Univibe page you'll see I have an electronic speed control circuit that can be adjusted to suit any resistance sweep range from a std 100k wah pot ... the only tricky part is that you need two fairly matched opto-couplers to make it work - I use a two point method, ie., match at 1mA and 10uA ...

[Stratomaster]

Thanks Eb7+9, but again, I don't have a standard wah enclosure.  In fact, a normal wah pot wouldn't even fit in this enclosure without extensive modification.  It's an enclosure perfectly suited for this application (turning a 24mm dual ganged straight shaft pot) minus the short throw.  I suppose I can go the belt sander route and see if I might change the linkage system to get more rotation out of the pot.  Other than that, I guess I'm SOL. 

The fact that I can put a standard 24mm 100K pot in this enclosure and go your route is not lost on me though, and it is a very clever circuit!

-Omar

[R.G.]

I really appreciate the offer, but I have an unusual wah pedal enclosure that I'm using for the Neovibe.  It uses a 2 bar linkage with a set-screw on the pot shaft to rotate it.  I can take the "heel" end of the rocker pedal to a belt sander and maybe coax out another 1/8"  rotation out of the travel, but I'm not entirely sure that will cover the entire the full travel I'm looking for.  Also, if it's just a matter of a few tapering resistors to accomplish this electronically, then that is much easier than risking irreversible damage to the enclosure.  No matter how much "rack" I have, it won't help this one particular application.  Thanks again.

A few tapering resistors probably won't get you there, unfortunately.

However, you are set up just about perfectly for an electro-optical solution. If you use a couple of LDRs, or better a centertapped one so you don't have to waste your time matching them, you can sub in the CT LDR for the dual pots. Then you rig a light source and a mechanically actuated shutter to uncover the LDRs to the light with your mechanical travel. This can be a rotating pierced disk, a sliding tapered shutter, a movable black cloth cover like Moreley used to use, any number of things.

[Stratomaster]

A few tapering resistors probably won't get you there, unfortunately.

However, you are set up just about perfectly for an electro-optical solution. If you use a couple of LDRs, or better a centertapped one so you don't have to waste your time matching them, you can sub in the CT LDR for the dual pots. Then you rig a light source and a mechanically actuated shutter to uncover the LDRs to the light with your mechanical travel. This can be a rotating pierced disk, a sliding tapered shutter, a movable black cloth cover like Moreley used to use, any number of things.

To everyone who answered, thanks!  You've given me a lot to think about and make a plan.

R.G. you are a god amongst men.  I really appreciate your insight (especially in support of your own layouts/designs).  Been hoping to run into you if you're still in Austin to shake your hand and say "Thanks."

-Omar