Due to a combination of just receiving a picture with a rare perspective
of my antennas and recent discussion of Beverage vs. transmit antenna
spacing I thought that I'd offer a link to a picture of my antennas. It was
taken from the vantage point of an airplane's view of them. Due to the
highly directive nature of the Beverages during actual reception, their
coupling to my transmit vertical array is minimal at best. The transmit
array has three parasitic elements in-line to Europe (or the South Pacific).
Another element (what I call a High Hy-Tower--a Hy-Gain Hy-Tower
which has three added tower sections) serves as a parasitic element
towards Asia or South America. You have to have a good imagination
to see the Beverage antennas from the view of the airplane. Because
of that I've hand entered their approximate positions. The 56? Beverages
actually continue to the left of the picture much further than shown, but,
like the actual airplane view, they can't be seen due to being hidden by the
trees at the airplane's angle (the Beverages come close to the trees, but
never through them).
Towards Europe I phase two parallel 881' Beverages at 56? that are
spaced six feet and stagger fed about a quarter wavelength apart.
That combination is then combined with a much wider spaced 1325'
Beverage at 43?. Since their azimuths are not the same, their spacing
varies. The 43? Beverage is fed at a point "behind" both of the 56?
Beverages. The three European Beverages are combined via two
MFJ-1026 units. Many on air tests have shown that the amount that
reception is improved is virtually identical when using just the two
close spaced Beverages vs. just one of those with the wider spaced
Beverage. The differing azimuths don't improved reception in a
single direction, but permits greater range of slewing the main lobe.
Besides the obvious advantage in varying the lobes direction, I've
found that it also permits easier observation of the amount of slewing
of the signal on a given day. It does take a greater familiarity with
the adjustment of the MFJ-1026 controls than a simple switch to a
different Beverage, but I found a greater feel for the state of conditions
once that familiarity was learned.
Anyway, I've probably gone into too much detail for the reflector already,
so you can the airplane view of my antennas at:
http://images.andale.com/f2/115/106/3610785/1043225113391_AirPixBv.jpg
73, Bill K0HA
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