GetLoFi has a great tutorial on how to circuit bend a Protech Drum Toy. The website has all the schematics and more pictures so you can make your own. Looks like a great way to get into the circuit bending craze.
I’m very fond of the Protech Drum Toy (or the “RY-1286T” if you read it’s most likely peeling label on the back), and it has special significance for me, as it was the first toy that I ever circuit-bent. With instruction from Patrick from Roth Mobot at a free workshop in 2005, I was able to find and figure out how to wire a pitch bend and a noise/buzz bend. Thus was born the Drum Invader, and it remains one of my favorite projects to this day.
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