As a ham radio operator, I have a unique opportunity to work at one of the USGS Geomagnetic Observatories. The observatory has been around for over 50 years and produces data about the earth's geomagnetic field. I'm just learning about the field and am by no means an expert. Everyday, I walk in and see the real time data spooling out on a computer screen and wonder how it relates to propagation. Here are my notes and links.