This great infographic looks like it could really help me figure out who’s talking on all of those data channels I pick up with my RTLSDR.
Click through for the full size, a 3.5MB JPEG. You could also get your own wall sized poster in high quality directly from the U.S. Government Bookstore for $12 with free shipping.
A pdf and text version of “United States Frequency Allocation Chart” is available here:
http://www.ntia.doc.gov/page/2011/united-states-frequency-allocation-chart