Find plenty of new and old reading materials here.

Information on DMR

Lots of articles on antennas.  UHF to HF

Interesting link about the telegraph used in the Civil War.  Link submitted by Johyn Hager, N4KJU.

Propagation map for ham bands.

Listen to sdr’s from all over the world.  The ham bands plus  shortwave broadcast and utilities are available.  Many different modes are also available.