I built my first project (I found the box at a thrift store this morning) that was inspired by the Megadrone initially. It’s using the CD40106 to send out three tuneable oscillators, each with their own volume control. I did something wrong when translating from breadboard to build, but I sort of like how chaotic it is so I’m just calling it my first synth child. It sounds almost like the chip is being starved, I’m not really sure! here’s a video of it