There was a thread about this on the 160 reflector. I think people
incorrectly assume interferometer or other nulling/ peaking techniques will
supply the true optimum wave angle, but that isn't the case at all.
Unfortunately the wave angle would only be measured at the height of the
test antenna.
For example, with a 40 foot high antenna on 160 or 80 meters, any
horizontal signals would appear to be high angle. That's because the earth
"filters" out any low angle horizontal signals. The only low angle signals
would appear to be vertically polarized, and you'd have no idea of the
"real" optimum wave angle or polarity leaving the ionosphere. (This is why
a Beverage, with a low horizontal wire, at low wave angles responds to only
vertical signals, and why horizontal antenna performance should only be
measured at short distances unless WAY up in the air in terms of distance
between the antennas!)
If you have a really tall tower and measure signals on ten meters, by
varying height of a phased array you could get an idea of the wave angle.
But even at 300 feet on ten meters signals would still be somewhat
influenced by the earth!
You might never find the true optimum angle on lower bands because tower
height would be restricted to small portions of the wavelength, but you
could find the optimum wave angle for the mean height of your array. That
is probably all we need or want to know anyway.
> Where is a source of incoming angle by freq, etc? Has anyone ever
> *Measured* incoming angles carefully?
>
> 73, Guy.
73 Tom
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