of course its right. there are seasonal variations in propagation and there are
skew paths that are more likely at some times of the year. but there are also
daily variations, they might as well say this:
"If your antenna is fixed in one direction, ..... you will notice that your
antenna works perfectly only during morning......... Why is this so?
Ionospheric conditions vary by time of day. This can cause deviations of up to
90
degrees from the direct path."
note, here in the north east u.s. we often get 10m and 15m openings to europe
when beaming southeast in the morning as opposed to the 'normal' northeast. and
fixed antennas pointing north east don't work well.
they could also relate that statement to the 11 year sunspot cycle, again as
here in the n.e. u.s. the skew paths are more likely to be noticed when there
are fewer spots and the normal direct path doesn't open at all. in that case
fixed antennas to the north east won't work as well as rotateable ones for years
at a time.
"Tim Makins, EI8IC" wrote:
>
> Anyone care to comment on this page ???
>
> http://sommerantennas.com/seasonal_variations.html
>
> Its saying that..
>
> "If your antenna is fixed in one direction, ..... you will notice that your
> antenna works perfectly only during fall and spring......... Why is this so?
> Ionospheric conditions vary by season. This can cause deviations of up to 45
> degrees from the direct path."
>
> If this correct, O Learned Ones ?? Because if so, all those antenna charts
> and pointing programs need a calendar built in, and fixed wire beams are
> only useful with a wider beamwidth....
>
> Tim, EI8IC
>
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