Topband: 160 Meter Propagation

[Thomas Giella]

Bob NM7M Said: 
I hate to say it but I do not recognize that as a principle that follows
from Maxwell's Equations, as applied to propagation. Maybe you can
amplify on your remark. 

Thomas KN4LF Says: 
    It's kind of like not seeing the forest for the trees. If
160 meter propagation does not follow the great circle route due to
absorption through partial or total daytime stretches along the route,
then it is following the path of lesser or least resistance, plain and
simple. Lightning does the same thing, it usually follows the path of
least resistance. 
    As a Meteorlogist I'm aware of NO being trapped in the
sunless winter polar vortex and it's southward leakage, a weather or
meteorological process, from my point of view. The NO leakage to 30-40N
lat. which is ionized by the sun and beefs up the daytime D layer can
and does allow D laer existence after local sunset, as recombination is
not instantaneous. I base my thoughts on the work of E.S. Kazimirovsky
and V.D. Kokourov, Geomagnitism And Aeronomy Vol 35, No 3, 12/95, page
305. These effects manifest themselves in bursts of overabsorption in
the D layer and helps to explain some of the QSB we see on 160 meters
+/_ local sunset. Ozone depletion is also a process tied to the polar
vortex. 
   I guess the bottom line is; there is much to still learn and it
keeps 160 meter operation fun and hairpulling. 

Take Care,

Thomas KN4LF


--
FAQ on WWW:               http://www.contesting.com/FAQ/topband
Submissions:              topband@contesting.com
Administrative requests:  topband-REQUEST@contesting.com
Problems:                 owner-topband@contesting.com