Antenna polarization plays a large role in the success of a long haul DX
contact. As a medium frequency RF signal traverses Earth's magnetic lines of
force in a perpendicular manner on high and mid latitude paths say between W3
land and SM, higher angle horizontally polarized signals are more readily
absorbed then lower angle vertically polarized signals. On other propagation
paths on the globe opposite results can be found, i.e. horizontally polarized
signals suffer less absorption on a propagation path between VK6 and W6 or S9
and W4.
Southern U.S. QTH's like Florida and New Mexico to S9 may be better via higher
angle horizontally polarized antennas. The N.E. U.S. probably elliptical
polarization via an inverted L. Higher latitudes via a vertical. Of course
though what complicates the matter is that RF often changes polarization as
it's is refracted.
Magneto Ionic Power Coupling expert Bob Brown NM7M has a good educational post
on this bugaboo on the May 2002 Topband Reflector. The thread can read in it's
entirety by going to this link
http://lists.contesting.com/_topband/2002-05/msg00087.html .
73 & GUD DX,
Thomas F. Giella, KN4LF
Space & Atmospheric Weather Forecaster
Plant City, FL, USA
Grid Square EL87WX
SKYWARN Observer # HIL-249
SWFWMD Observer #574
PODX 070 PSK31 Member #349
Yaesu FT-840 & PSK31 News Group http://groups.yahoo.com/group/yaesu_ft840
10 & 6 Meter Propagation Beacon Network http://www.PropNET.org
Solar Space Weather & Geomagnetic Data Archive http://www.kn4lf.com/kn4lf5.htm
HF/MF Radio Propagation Theory Notes http://www.kn4lf.com/kn4lf8.htm
160-10 Meter Amateur Radio Resources and More http://www.kn4lf.com/kn4lf.htm
Florida Space & Atmospheric Weather Institute http://www.kn4lf.com/fsawi.htm
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