For TopBand Reflector:
Tom, KN4LF writes:
>>In simpler terms the MF RF transmitted from Norway towards Maine in New
England that traverses the "radio" auroral oval region, usually suffers
absorption and/or unpredictable scattering and does not arrive in Maine.
Let's call this the path of "most" resistance. As the transmitted signal
from say a 1/4 vertical, is not a narrow beam like a 300 gig laser, it has a
relatively wide horizontal beamwidth and in the vertical plane probably
radiates a signal between 90 and 15 deg., that reaches the ionosphere. Due
to the wide range of angles radiated in the horizontal and vertical planes,
some of this signal skirts south and west of the "radio" aurora oval and
arrives in Maine from the SE instead of a more expected NE direction. In a
practical sense you can say that the skewed signal arrived via the path of
"least" resistance or absorption. This is especially true if the signal
arrives via the E-Valley/F Layer duct, versus multiple refractions between
the E Layer and land/ocean surface.<<
Isn't this implying - confirming that we are (also), perhaps more on low
bands, propagating waves by ducting/refraction, rather than
bouncing/reflections by the atmosphere/ionosphere? And that we can explain
more of those "weird" modes by ducting as I described it in my article in CQ
Magazine, June 1980?
http://members.aol.com/ve3bmv/bmvpropagation.htm
Not based on physics laws, but on observations over the years using high
performance antennas.
"Mirrors" theory sure would have problems why signals take the turn rather
than go bouncing straight according to rules of geometry.
73 and CU in the contests!
Yuri, <A HREF="http://members.aol.com/k3bu/index.htm";>K3BU</A> , <A
HREF="http://members.aol.com/ve3bmv/index.htm";>VE3BMV</A> ,VE1BY, etc.
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