http://www.solarham.net/
Propagation & Spotting
intended for or likely to be understood by only a small number of nerds & geeks with specialized technology knowledge or interests.


http://www.ztlearn.com/ss



Contesting
DX & DX News
Maps & Charts
Logging & QSLs
Morse Code

 
http://www.globaltuners.com
http://livehams.com/

Rules & Orgs.

Electronics

Building- Kits & Homebrew
SDR & Online Radios
https://www.jeffreykopcak.com/2017/03/15/ohio-section-journal-the-technical-coordinator-march-2017-edition/
Arduino & Raspberry Pi