23 years ago (!) I wrote:
K9LA wrote:
>*And another thing that clouds the issue - many of our antennas have a *
>*response to the other polarization. For example, Beverages respond to *
>*horizontal polarization off the side. *
Very true! In fact, noticing signals on my Beverage system that
were skewed by 90 degrees was usually a clue to check my dipole!
When this happened, the dipole would often (but not always) be
the best antenna. The exception to this was when signals traversing
the Auroral zone were skewed by disturbances (K index 4+). Usually
this sort of skewing would shift signals by less than 30 degrees in
azimuth but some really large disturbances would cause shifts up to
90 degrees! But that's another story and a completely different
propagation mechanism.
Back to the present, since nearly all horizontal antennas are low (in
wavelengths),
there is no way to determine azimuths (since high angles equate to
omnidirectional).
Only a Horizontal Waller Flag up >100' can to that, and these would be
low horizontal
angles, not high angles.
I put up an Inverted-V on my 30m tower in January 2004 in order to
have a "high-angle" antenna for those cases when we have that type of
propagation. The *blue *plot below shows the elevation pattern. It
turns out that 30m is about the optimum height to maximize radiation
straight up (7.14 dBi at 90 degrees), which was my goal for this
antenna. The other plot is a quasi-4 square which shows low angle
vertical polarization angles for comparison.
http://web.archive.org/web/20191102091231/http://users.vnet.net/btippett/new_page_10.htm
73, Bill W4ZV
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