Homebrew Vactrols

[Paul Perry]

Ironically, I was recently repairing an Ibanez wah pedal
which uses a led/ldr arrangement with a shutter connected to
the footpedal.
The original ldr was missing... after trying every ldr I could find,
the only one that worked was one I got by cutting a CLM600
in half!!! (the critical requirement was small size, and a very low
resistance at max illumination)

paul perry melbourne australia

BTW for diy use I think the main variable would be the response times 
of the ldr. Which is always faster for attack than decay.