Version 1.0 of the ChronoDot has a critical flaw. It does not fit on a standard breadboard. Because of it’s round shape, one can’t use pins outboard of the PCB. To fix this shortcoming, I decided to shave it down to size. A few passes on my disc sander and, I can now just get 1 row of pins on each side. See the photo below.
However, after doing this the ChronoDot stopped working. Apparently in the process of shaving the PCB edges, I cut a trace. Sure enough, after a couple of checks with my trusty Radio Shack Digital Multimeter (Model 22-820), I discovered I had cut the trace going to a ground plane which fed the ground pin of the DS3231. If you look closely at the photo you can see my “greenwire fix“. My wire is actually “white”.