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[TowerTalk] Measuring DX Performance of Verticals

To: <>
Subject: [TowerTalk] Measuring DX Performance of Verticals
From: (Ward Silver)
Date: Wed May 7 12:58:58 2003
Yeah, but actual performance would depend so greatly on local ground screen
characteristics, terrain, and quality of installation and connections that
any one-time tests would have little merit on a long-term basis.  The
subject of ground-screen/radials has been covered thoroughly elsewhere.

73, Ward N0AX

----- Original Message -----
From: "Pete Smith" <>
To: "Ward Silver" <>; "Towertalk Reflector"
Sent: Wednesday, May 07, 2003 9:54 AM
Subject: Re: [TowerTalk] Measuring DX Performance of Verticals

> 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
> >sky-wave path is pretty much an exercise in futility.  Signal levels
> >wildly +/-20 dB in a matter of seconds, so comparisons would have to be
> >on a second-to-second basis..  You would need synchronized antenna
> >systems and some fairly sophisticated test gear to acquire the data and
> >separate it into the individual signals.  This is out-of-scope for
> >tests and unlikely to provide any real meaningful data.  I have no reason
> >this point to question correlation between the range tests and
> >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
> >sky-wave tests."
> >
> >Now, about the horizontal-vs.-vertical question...there are many
> >in which horizontal antennas have been observed to work better over DX
> >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
> >antennas."
> Couldn't the signal produced at the VERY low angles between local sites
> vary substantially depending on the extent to which a given vertical
> 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
> The World HF Contest Station Database was updated 11 April 03.
> Are you current?

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