This PCB is a scaled-down version of the Looney board, implementing up to 6 oscillators using a single 40106 chip, plus a diode mixer. It's primarily intended for workshops, and can be built by novices in a couple of hours. We've presented this project numerous times at libraries, arts organizations, schools, and Makers Fairs, with participants as young as 12.
Complete workshop instructions are given below, implementing a 3-oscillator light controlled synth from Nicolas Collins' excellent book Handmade Electronic Music: The Art of Hardware Hacking. The PCB is laid out to support many options, and supports experimentation and building many of the popular CMOS oscillator projects found around the net.
This PCB was originally made for TECHNE, a fantastic educational organization whose programs introduce young women and girls to technology-focused art making.