AIRCON

[deadastronaut]

been having a lot of fun with this INFRA RED control circuit. which i called A'IR'CON.

been controlling , speed, depth, vol, feedback, wah, filters etc etc....with cool results...

much better than LDR's which are a pain with light conditions...this is a lot less fussy.

much more useable....

try it, hook it up to a pot , great fun....

[Kipper4]

Neat.
Thanks Rob. This is going on my list.
Thanks

[deadastronaut]

cool, yeah i reckon you'll like it man...pretty nifty. 

much better than all the ldr/proximity stuff ive tried...

[Mark Hammer]

This is going to need a little more explication.  The only thing I'm sure of is that LDR1 is replacing a resistance somewhere.  I have no sense of what is controlling it, though, given the inclusion of 4 LEDs.

As an aside, I have used an LDR mounted to the surface of my guitar as an expression-pedal substitute, where an expression-pedal jack only expects a variable resistance to ground.  The caveat is that it requires an available light source to block with one's pinky.  Does this get around that sort of constraint?

[EBK]

If I understand it correctly, the IR from TX is reflected off of something (a hand or a foot) and back to RX.  So, it is like the LDR-only approach, but has its own light source.  Might possibly be improved if the IR were modulated and the RX had a filter loosely matched to that frequency (to reduce the effect of ambient IR).

[deadastronaut]

here you go, a demo...a vid paints a thousand words..