Thread: Vertical Yagi?
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Old July 13th 08, 09:28 PM posted to rec.radio.amateur.antenna
John Ferrell John Ferrell is offline
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Default Vertical Yagi?

On Sun, 13 Jul 2008 11:22:44 -0700, "Bryan"
wrote:

John Ferrell wrote:
Why do we always mount our HF Yagi's in the horizontal plane?
Antenna maintenance would be much easier for those of us with tilt
over towers if the antenna were in the horizontal plane when down for
maintenance!

John Ferrell W8CCW


Over the past 38 years, I've had HF yagis... a homebrew 3-el 15m monoband
yagi (16' boom) and 3-element triband trap yagis (12' booms) on tiltover
masts. I've never encountered maintenance issues with operating them in the
horizontal plane. A step lader is all that's needed to reach the driven
element, and the antenna can be rotated to reach both parasitic elements.

It seems to me that while Front/Back ratio might be similar, a vertically
polarized yagi would have a significantly reduced Front/Side ratio. If
operated in the vertical plane, I'm guessing that performance may also be
adversely affected by a conductive mast in the near-field. If performance
was same/similar and maintenance was much easier, I think you'd see many
more vertically polarized HF yagis.

Bryan WA7PRC

There have been several very credible posts that have convinced me
that I do need to stick with horizontal polarization with the Yagi.

Fortunately, the physical limitation of "no ladders" will go away in a
few months as I continue my recovery from two knee joint replacements.
However, as I get older I may find the limitation returning. I want to
be prepared for that time.

My antenna is modest in that it is only a Cushcraft A3S and I
generally keep the crank up antenna height at about 50 feet. This area
(Greensboro NC) does get an occasional hurricane and some ice storms.
There are times when I would like to reduce my risks on the forecast
weather.

I expect I will pursue a lighter (home brew) version of the Tilt Plate
system.

Currently the coax is fouled at the rotor and I will need outside
assistance to clear the problem. It is not a big issue but I do like
to solve my own problems!

John Ferrell W8CCW