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Re: [TowerTalk] Tuners

To: towertalk@contesting.com
Subject: Re: [TowerTalk] Tuners
From: Rik van Riel <riel@surriel.com>
Date: Mon, 29 Nov 2010 13:01:16 -0500
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
On 11/27/2010 09:08 PM, Rick Karlquist wrote:

> VK1OD did a nice analysis.  Unfortunately, many hams are simply
> in a mode of "don't bother me with facts".  They desperately want to
> believe in the paradigm of a tuner in the shack and a simple all band
> antenna at the other end of the line, such as a plain vertical conductor,
> or a random wire, or a "loop skywire", a "G5RV," or some sort of "Windom"
> antenna.  All continue to live on in ham folklore.

The big horizontal loop antenna seems decent, provided it is
cut at a length that gives it a good match on not just the
primary band but also the others:

http://surriel.com/radio/multi-band-hf-loop-antenna

One big factor that cannot be overlooked is the antenna
height.  If the antenna is low, performance will suck, if
the antenna is high it will have a low takeoff angle and
do fairly well.

It is also an easy match to the radio, with an SWR below
2:1 for pretty much all of 80 and 40 through 10.

As for windom / g5rv / random verticals ... they all have
takeoff angle and/or matching issues that make them essentially
single band antennas - some of them not good at any band :)

I realize that a properly installed beam antenna will outperform
a wire antenna any day.  However, given how poorly some people
install their beam antennas (30' tower, lossy coax, not exactly
sure where it's pointed, etc), I would not be surprised if a
properly planned and installed wire antenna outperformed a fair
number of the poorly installed beams out there.

My point?  Even a good antenna can be a poor performer if the
entire antenna system is not carefully planned.  Conversely,
a simple wire antenna can be a decent performer if the system
around it has been carefully planned (low SWR loss, good takeoff
angles, etc).

What matters is the antenna system.

-- 
All rights reversed.
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