Converting a standard wah to an auto wah

[mcallisterra]

Auto wah may not be the best term, as I see people call envelope filters 'auto-wahs', but I mean an LFO driven one with depth and speed knobs.

Basically, I have a Vox V87a (or something) wah that I never use, kinda got tired of the treadle side of things. I was wondering if it's possible to rip the circuit from that and have it run through automatic cycles with a depth and speed knob like a phaser etc. would have.

I'm not great at this pedal stuff by any means; I have built a few BYOC pedals and a few MadBean ones but never done any modding or hacking. So my questions are:

1) Is it possible?
2) a) How would I go about doing it?
b) Would it beyond the scope of what I could comfortably manage and hence not be worth it?

You guys blow me away with your intimate knowledge on this subject so I'd love to hear your thoughts and recommendations. Thanks! 

[lars]

Since the wah effect is controlled by the changing resistance of a potentiometer, you could conceivably build an "auto wah" by replacing the potentiometer with a Vactrol circuit (LED/LDR combo), like what's used in many tremolo circuits. So yes, it is definitely possible, but would most likely be a pretty labor intensive/ trial and error modification to get the resistance sweep correct for a wah. I know my Vox wah has a pretty tight range of less than 100k where the effect is in the "sweet spot". Anything outside of that and you don't really hear any effect at all, just volume change.