Hi Bob and all,
> I was talking about paths between low-latitude stations like 9V and
> stations at higher latitudes, like in the USA. At low latitudes, 160
> meter propagation toward the USA is nearly along the direction of the
> geomagnetic field. That is called quasi-longitudinal propagation in the
> language of magneto-ionic theory and if you work with the PropLab Pro
> program, you find that ducting is a common feature for radition angles
> between 10 and 25 degrees. That gets signals into the USA with little
> loss due to ground reflections or traversals of the lower, lossy part of
> the ionosphere (even at night).
It's well established the average noise level near the Equator is
much higher than noise at higher latitudes.
It's also well-established the even quiet urban locations are many
dB noisier than rural locations.
With that in mind, how do we know it is propagation and not noise
levels that make low latitude stations "alligators"?
73, Tom W8JI
w8ji@contesting.com
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