Regards absorption on 80, or any other band for that matter, as
reported by guys in the upper midwest, try the following exercise:
Take a globe, draw a circle with the center at the north geomagnetic
pole and tangent to a line from Minneapolis to Gibraltar. That circle
approximates the widest area of auroral activity up to an A index of,
say 40 or so. Above 40 it starts to get bigger. Look at our paths
from your location to the areas where your qsos and multipliers are
located. Next look at the path from, say Fargo, ND, to these same
places. You will notice that the path to all of Europe and central
Asia must pass through the aurora zone. In my experience two things
happen when aurora is present (A index and K index are up). One is
absorption, experienced as attenuation of signals. The other is one
way skip. Although not common, it is very real and can result in
bizarre situations. For instance signals from the lower 48 reading 20
to 40 over 9 in Anchorage with no propagation in the reverse
direction. With a little effort, you should be able to use the globe
to approximate the size and shape of the "black hole" and to
appreciate what contesters in various parts of the country have to
deal with. You should also be able to better appreciate the
desirability of a contest site in New England!!
73
Jim
W0UO/5
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