Some years ago I bought a booklet called ‘making music with the 566’ by Thomas Henry. The first time I read it, I understood maybe 10 percent. Since then, every year or so, I’d read it again, and it started making more and more sense. And last year I decided it was time to try and make a PCB for it. So here it is. I’ve added a wave shaper to turn the triangle wave into a saw wave. I made some minor mistakes in the first PCB design, but these are fixed in the schematics below.