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(meteorobs) Reception
300 km is very short for Es. In fact, I'm surprised that you get much MS
from that distance. Anything under 600 km is difficult for both MS and Es.
Your description is consistent with enhanced tropospheric scatter, or, more
likely, tropo ducting. This is the time of year that it becomes rather
common in some parts of the continent. Some places experience it quite
regularly. The signals can be very strong (or weak), are usually (not
always) in one particular direction or quadrant, usually are good out to
200-400 km but can be good to well over 1000 km on rare occasions. If it's
ducting, the signals can be caught in the "duct" and, if the duct is
elevated above the surface of the earth at the midpoint, can even "skip
over" stations in the middle.
There are a couple of other things your reception could be. Auroral-E
comes to mind, but is much less likely, and really doesn't fit your
description.
For more on all this, the ARRL book "Beyond Line of Sight" is a reprint of
the best propagation articles from QST over the years. Think it's still
available, about $12 (US) from the ARRL. From England, the RSGB's "VHF/UHF
DX Book" has a good propagation introduction, but "Beyond Line of Sight" is
probably the best thing currently available. It also has some good stuff
on MS, tho now this section is out of date. (See if your book store has
the Summer issue of the magazine "CQ VHF" as it has a good summary of MS work).
73, Shelby, W8WN
Shelby Ennis, W8WN - EM77bq - KY
w8wn@arrldot net
w8wn@amsat.org
Web: http://www.qsldot net/w8wn/
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