http://en.wikipedia.org/wiki/HF_radio#Propagation_characteristics http://en.wikipedia.org/wiki/HF_radio#Propagation_characteri... I'm no expert in HF, but my g

http://en.wikipedia.org/wiki/HF_radio#Propagation_characteristics http://en.wikipedia.org/wiki/HF_radio#Propagation_characteri... I'm no expert in HF, but my general understanding is that while auto band-hopping could be helpful, you are never guaranteed there is a usable band.