Topband: HFTA, Radio Arcala, general comments

Richard Fry rfry at adams.net
Thu Oct 25 18:11:56 EDT 2012


Ward N0AX wrote:
>... The electron gyrofrequency (I just *love* saying "gyrofrequency", don't 
>you?) in the lower layers ... is much closer to 1.8 MHz and causes the wave 
>coupling to change dramatically in ways that are not well understood. This 
>changes with latitude and time of day (or night).  ... etc

At least as important as understanding how 1.8 MHz skywaves interact with 
the ionosphere is understanding the space-wave fields that are actually 
_launched_ by a monopole at various elevation angles toward the ionosphere.

Those fields are not accurately described by NEC far-field elevation 
patterns, which show the fields/pattern at an ~infinite distance over a flat 
ground plane of ~infinite extent.

NEC calculations are accurate for those conditions, however those conditions 
do not exist in the real world.

R. Fry 



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