Propagation and Ionsonde
 

The bands here up north seem as bad as I can ever remember. While I
realize we are at a solar minimum, I sometimes seek reassurance that my
antennas do indeed still work. With that in mind, I have been trying to
research high latitude propagation. I do not live far from the HAARP
facility in Gakona, Alaska, so I have been rooting around their website:

http://www.haarp.alaska.edu/haarp/data.fcgi

I find the HF waterfall plots and the ionsonde charts to be of
particular interest. The HF waterfall is fairly simple to read, but I
find interpreting the ionograms to be a little more challenging. I did
a google search of how to read an ionogram and came up with this site
which sheds a little light:

http://www.mporzio.astro.it/CVS/index28_evA.html

The Italian site also links to some other ionsonde facilities. I would
imagine that radio users down south may not find much use for the
specific HAARP data, although I would guess it might help predict over
the pole paths.

I am curious how others may interpret the ionsonde data, or if anyone in
the group has experience reading these charts.