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[TowerTalk] Measuring DX Performance of Verticals

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Subject: [TowerTalk] Measuring DX Performance of Verticals
From: (Pete Smith)
Date: Wed May 7 12:55:22 2003
At 09:49 AM 5/7/03 -0700, Ward Silver wrote:
>The bottom line is that trying to make any kind of an A/B comparison over a
>sky-wave path is pretty much an exercise in futility.  Signal levels swing
>wildly +/-20 dB in a matter of seconds, so comparisons would have to be made
>on a second-to-second basis..  You would need synchronized antenna switching
>systems and some fairly sophisticated test gear to acquire the data and
>separate it into the individual signals.  This is out-of-scope for amateur
>tests and unlikely to provide any real meaningful data.  I have no reason at
>this point to question correlation between the range tests and performance
>over a low-angle sky-wave path.  Introducing the sky-wave path would also
>introduce so many uncontrolled variables that any conclusions would be of
>questionable validity. These are all code words for, "We are not going to do
>sky-wave tests."
>Now, about the horizontal-vs.-vertical question...there are many instances
>in which horizontal antennas have been observed to work better over DX paths
>than vertical and vice versa.  The angle at which signals arrive changes
>dramatically over the course of a single band opening, as well as the
>preferred polarization.  Having different antennas on the low-bands often
>pays big benefits, no question.  This is code for "You can't have enough

Couldn't the signal produced at the VERY low angles between local sites 
vary substantially depending on the extent to which a given vertical design 
is affected by ground quality and/or radial fields.  This is sort of a 
cousin of the question I had about the tribander tests, but if anything 
would appear to be a more serious issue with verticals.

73, Pete N4ZR
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