> propagation path). Couldn't the mechanism be simple refraction if the
> refracting layer is twisted? Is there any evidence of ionospheric
> layers being twisted under certain conditions just as they seem to be
> tilted at sunrise?
It's a real mess in the soup of scattered ions up in the sky on 160.
That's why we have skewed paths and scattering, and that's why
we never universally agree what works best. That's why no one can
predict an opening.
For example, off-peak my 200 ft vertical beats a 150ft high dipole
by 20dB or more. On-peak, the vertical only wins by a few dB.
Off-peak, large receiving arrays make a huge difference. On-peak,
the difference is much smaller.
What we declare "works best" is more a matter of how good the
best less-than-perfect antenna we have works compared to our
other less-than-perfect antennas, rather than how propagation
actually works.
All the multipath and scattering during a good peak makes
everything work about the same, but that certainly doesn't tell us
how the signal gets from point A to point B. It is almost certainly
just a local effect.
W1BB always felt it was because the big wall of dense ionization
was approaching, and I agree. I can beam right into that wall and
hear scattering from signals that isn't there during dark.
73, Tom W8JI
W8JI@contesting.com
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