A long time ago I had circuit bender a mini “Buzz L’Eclair” (Toy Story) voice changer toy (the “Roboto Pitch”) and the sound was good so I decided to bring it up to date and make it something more complete today, with LFO + env …
my old version :
and now 
:
i’ve added a Casper Electronic LFO with Shape Rate and Depth, switch for long or short cap
and a Optical Enveloppe for long pulse with also a switch for long or very long (1000uf cap!!!)
here all the build process
demo of the FX Pitch Box with the Minipops dum machine
more details and schems on my blog