Thanks for the link! Key phrase for me, which does agree with the table in the
ARRL books: "Obviously you're much better off to using thirty two 1/8-wave
radials as apposed to a smaller number of longer radials."
1/8 wave is 60 feet and in two directions that (mostly) fits within my property
lines. But in two other directions it doesn't (things like driveways and
neighbors houses in the way!!!). Looks like I'm still doing guerilla radial
deployment on winter nights and rolling up in the AM! I would be real lucky to
deploy even 12 1/8-wave radials.
Tim N3QE
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Jim Brown
Sent: Thursday, September 27, 2012 3:07 PM
To: topband@contesting.com
Subject: Re: Topband: Short radials?
It's important to note that this data is for AM broadcast towers, which in the
time frame when this work was done, were mostly a quarter wave tall to 5/8 wave
tall. While it is considered the standard for that sort of antenna system and
budget, it is not particularly relevant unless you have a quarter wave vertical
and a lot of money to spend on copper.
The work by N6LF is far more relevant to the question at hand, because it looks
at radials in the context of shorter antennas (as a fraction of a wavelength)
that most hams use, and that this post asked about.
http://www.antennasbyn6lf.com/2010/03/relation-between-vertical-height-and-radial-length.html
73, Jim K9YC
On 9/27/2012 10:14 AM, Richard Fry wrote:
> The measured data linked below shows how the number of buried radials
> affects the performance of monopoles of various height to 90 degrees,
> for an applied power of 1 kW. Earth conductivity at the test site was
> about 4 mS/m.
>
> http://i62.photobucket.com/albums/h85/rfry-100/BLandERadials.gif
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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