[CQ-Contest] It's not the sunspots, folks

Carl Luetzelschwab carlluetzelschwab at gmail.com
Tue Nov 1 14:49:44 EDT 2016

Yeah, CQ WW SSB was tough. I was hoping to pick up Zone 2 on 160m, but I
heard none of the active stations - even when they were spotted.

Unfortunately the declining portion of a solar cycle (where we are)
historically has the most geomagnetic field activity due to coronal holes.
CMEs (the other trouble maker) are more likely at solar maximum.

Ed N1UR asked about cosmic rays affecting 75/80m and 40m. For all intents
and purposes on 160m and HF, ionospheric absorption is inversely
proportional to the square of the frequency. So when we double the
frequency from 160m to 75/80m, the ionospheric absorption decreases by one
fourth. It would decrease even more (by one sixteenth) on 40m.

So if cosmic rays are going to affect us, it will be on 160m.

Carl (not Karl) K9LA

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