I knocked this one up last night and it's really noisy. I tested it before housing it and I thought "oh maybe it's just picking up noise because it's not yet inside a metal box" but it's noisy even after boxing it up, even on a battery (putting out ~8.6v).
I tested continuity at a few points and it seemed the ground might have been connected to the output but I couldn't replicate that when I checked about an hour ago. I might go back and redo the ground connections at the jacks with a bigger iron tip coz they're not great at the minute. I was super careful with the diodes and IC (how do you even test an IC with a multimeter?).
Any ideas folks?
Kit instructions