>Skewing even happens quite often on fairly short paths if they are
>obstructed. For example, LA3XI is often S-8 to S-9 plus here during
>summer when I point straight into the darkness, and he reports a
>similar path for him...straight into darkness.
>
>It just happens to be east for me, and south for him.
>
>So I think you are on to something Stan (and Thomas). It seems
>as you point out signals simply come from the direction of least
>absorption.
>
>73, Tom W8JI
>W8JI@contesting.com
G'day
It has been interesting to read the posts about skewed paths over the last
couple of weeks - interesting reading, but potentially confusing.
Tom W8JI makes an excellent and simple point above - from what I've
learnt/observed 1.8MHz signals always travel down the path where there is
least absorption - along a path which is the most (relatively) dark.
However, when it comes to how 1.8MHz signals are actually propagated
through an ionisphere - things get a bit more complicated.
That being said, as Bob NM7M says, there are only three known ways that
signals are propagated through an ionosphere:
"refraction by ionization gradients, scattering of signals by ionospheric
or atmospheric irregularities as well as irregular surfaces (ground or
water) and reflection by auroral ionization."
The mechanics of 1.8MHz propagation (i.e. the systematics of darkness) are
relatively straightforward and there are three clear and proven ways as to
how signals propagate. In the words of Scotty from Star Trek, to Captain
Kirk: "You cannae change the laws of physics, Jim".
If we are to make any progress in working out which of these three
propagation mechanisms are in operation at a particular time on 1.8MHz
(i.e. when skewing is apparently being carried out) as NM7M says, we have
to learn to report events in a complete and systematic way, in geophysical
terms - i.e. - date, time, frequency, geomagnetic and ionospheric
conditions - so that a proper analysis can be made.
It is fun having pet theories about things (I know, I have mine!), but NM7M
has taught me that this is no substitute for the laws of physics and good
scientific observation.
Let's put our egos to one side and start getting serious about the fun we
have on 1.8MHz. Let's also stop trying to complicate what isn't
complicated and is proven science. If we do that, we might actually make a
real discovery or two about how our favourite amateur band works.
Now, where should I put my ego?
Vy 73,
Steve, VK6VZ
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