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Re: [TowerTalk] elevated radials vertical

To: <>
Subject: Re: [TowerTalk] elevated radials vertical
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Sat, 9 Jun 2007 07:45:46 -0400
List-post: <>
> 120 radials might make a huge improvement with a single 
> band vertical on 80 or 160

 I've never seen a system where that happens. Almost 100% of 
maximum FS in any soil condition come with the first 40 or 
50 radials, assuming they are at least 1/4 wave.

The 120 radial myth comes from the BC industry where the FCC 
allows stations to short-cut certain complex field strength 
measuring requirements if they use 120 radials 1/4 wave 
long. Somehow people seem to think the FCC bases that on 
performance changes, but it is really all about taking the 
worse situation and overkilling it by a factor of two.

A lot of this is just subjective emotional opinion. Very few 
people actually measure anything meaningful, but when they 
do the general trend is you lose a few dB, perhaps 2-6dB, 
with a sparse elevated system close to earth and once you 
get the 40 radials or more it doesn't matter if the system 
is in the air or on the ground.

99% of antenna talk is really about how the antennas make us 
feel, not how they actually work.

73 Tom 


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