Note on Vertical vs. Horizontal polarization.
It is not just a question of polarization of the signals, but the difference
in the radiation pattern. Similar antennas, similar heights but different
polarization have drastically different patterns. Where horizontal has a lobe,
vertical has a null. So one has to be careful at what we are looking at - is
it because of polarization or because of difference in the pattern, or both.
So if you have two antennas H and V polarized at the same height, you are not
just switching polarization but also two different patterns.
Dual (-3dB) or slanted polarization use is not new. I used it on our
"slanted Quad" on 1976 St. Paul Island XJ3ZZ/1 DXpedition as described in my CQ
<<Antenna #1. Cubical quad, two elements, for 20 meter band. Because of poor
ground on the island, pure rock, the quad seemed to be the best solution in
that it provided a lower angle of radiation and more gain than a three element
Yagi at lower heights. The quad was tested in our backyard on a 20 foot tower.
Feeding the loop was the VE3BMV special, i.e., fed in the bottom corner of the
driven element in a square configuration. The antenna was tuned for the
middle of the 20 meter band, and the test showed surprising results. It was
the same as a TH6 at 70 feet. The important discovery was that the signal was
more stable and indicated no QSB, which was very noticeable on the TH6. This
was very encouraging. (Spacing was 8 ft. no balun was used, s.w.r. at resonant
frequency 1.2 : 1. The braid of the coax was connected to the bottom horizontal
side, and center conductor to the vertical side.) <<
Yuri, K3BU, VE3BMV
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
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