Well, to answer your question in the 5MHz, the 60M band, it's a very good band to use. The military uses it extensively. In the daytime, it has nice regional coverage from 50km to over 500km, and is a good choice for NVIS, (Near Vertical Incidence Skywave.), antenna. Meaning, the dipole is low to the ground, like 10 meters, or less, and you are using the ground as a reflector to intensify more signal going to the F2 layer, and bouncing back regionally. (If I understand the theory correctly.) At night, this band goes long, very long. More than 1,000km, and can skip over the first 400km. Amateur radio operators and the US Army actually did a test exercise last year to see if they can talk coast to coast to each other, and they did, with 100W, or less. The downside of 60M? This time of year it is very noisy with lightning crashes at night. I am trying to think what is on this band for you to monitor 60M for yourself to study propagation. WWV right at 5MHz even comes to mind from Fort Collins, Colorado. Then, there's WBCQ on 5130kHz,
http://www.wbcq.com/ Anyway, bottom line is, 5MHz, a.k.a. 60M band is indeed a good choice.