http://www.voacap.com/ is a great resource for visualizing propagation conditions based on month, time of day, frequency, location, etc.

You can calculate maximum usable frequency between two points or show a global map based upon your transmitter location with likelihood of successful contact to other points on the globe.

(not everyone is egghead enough to use ham gear post shtf
modded CB gear may have a resurgence)
Smoking Antennas for 20'ish mhz.
Omni Dual fed choose your polarization horizontal or vertical.
http://www.jogunn.com/index.php?page=sho....

$279? They were $125 in 1989 Thanks all you central bankers *******s.
Hit a QSO to Christmas Island from central NJ once,modded Cobra 2000
driving a pride dx-350 on the low side(ceramic tube all you jabber jaws know what that means = unlimited keydown time).

The omni had a nice mount to mast monolithic base.
I never had so much fun since my PDL II quad beam that I had to always go on roof and fix since my vent pipe mount sucked.