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Re: Topband: Elevated Radial Efficiency - an inordinately long post

To: <>,"W0UN -- John Brosnahan" <>
Subject: Re: Topband: Elevated Radial Efficiency - an inordinately long post
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Fri, 30 Nov 2007 08:46:43 -0500
List-post: <>
> W5UN did extensive A-B measurements between a collocated
> elevated radial system and an extensive, ground-mounted 
> radial
> system.  And Dave chose the elevated radial system for his
> 4-squares on 80 and 160.

Then that would be the very first actual A B field strength 
test, if made in a clear area free of other ground 
influences like old ground systems, that has ever been made 
besides the one at WVNJ and the half dozen I have personally 

A single test like that, if it truely showed an A-B 
comparison would mean more than all the articles for the 
past 20 years, although not nearly as much as the thousands 
of measurements RCA made in the 20' and 30's. As anyone who 
has researched this knows, the RCA tests were a turning 
point in antenna design. The very detailed measurements of 
real systems by RCA had the effect of stopping the common 
use of resonant counterpoises.

Negating that work would require at least reasonable 
scientfic method and actual measurements. That's something 
that has never been done to this date.

> I am reluctant to characterize Dave's extensive results 
> over many,
> many months of testing although I have visited with him 
> and looked
> at his arrays.  The best I can do is to encourage him to 
> make his
> tests public.  And I know that he is very happy with his 
> choice and
> the performance of his two arrays.

"Happy" isn't the issue, but data is.

1.) Prior to the 30's, virtually most systems used a 
resonant counterpoise. Radials were uncommon.

2.) In and around the 1930's it was found that a system of 
40-60 1/4 wave radials would get array efficiency up nearly 
to the maximum possible. This was based on thousands of good 
direct scientific measurements of actual test systems where 
only the ground systems were changed.

3.) The study was so overpowering the FCC simply doubled the 
number of radials required to get out on the flat part of 
the curve, and told broadcast stations if they used that 
many radials they didn't need to do efficiency proofs of the 
ground system. (The efficiency proofs established a minimum 
field strength, not a maximum.)

4.) Sometime in the 70's or early 80's a Ham radio article 
proposed simply insulating a buried radial would increase 
system efficiency. The article did not contain a single 
verifying field strength measurement. Still, some people 
strongly believed in that conjecture and it became a point 
of debate...despite lacking any attempt of actually 
measuring field strength.

5.) When computer programs came along, someone used a 
program that really had no verification of earth behavior at 
HF to model ground systems. That article, despite the lack 
of actual field strength measurements, started the current 

6.) Some BC systems, some even with unknown amounts of old 
radials and other metal in place, were used to " prove" four 
elevated radials would equal 120 radials. The problem with 
that is anyone who understands how those tests are made also 
understands they really don't measure array efficiency 
change between the two systems. I've already outlined why 
they really don't tell us anything useful to help resolve 
this debate.

7.) Later a few articles appeared that claimed even two 
elevated radials had nearly 100% efficiency. Again there was 
no verification.

8.) A few years later another article appeared, again 
without a single verifying field strength comparison, that 
proposed the reason some elevated systems showed bad 
performance was the radials were self-resonant and different 
in current. That article suggested reducing the radial 
length would increase the signal, but once again not a 
single verifying field strength measurement was made 
comparing the two systems.

This timeline has brought us to this point. We are at a 
place where some people strongly think four 1/8th wave 
radials, or even no radials at all, are better than 60 full 
size radials...and they will argue that point endlessly.

One would think in the past 20-30 years someone who proposed 
a theory that would undo the many thousands of RCA 
measurements (this is Radio Corporation of America, NOT the 
Radio Club of America sometimes referred to as "RCA" in 
modern articles) would at least do a few dozen FS 
measurements where only the radials were changed, yet there 
are virtually no field strength measurements of any kind 

In my opinion if someone wants to write an article claiming 
something is improved and challenging the traditional wisdom 
that was based on the extensive RCA (Radio Corporation of 
America) studies, they should at least directly measure what 
they claim is changed. Every technical article should at 
least make some attempt to directly measure the parameter it 
claims is being changed with reasonable logical science in 
the measurements. Then when the weight of evidence shows all 
the real work was wrong, I'll buy into it.

For me a technical paper or article is interesting and 
valuable when it has actual data. Not when it simply makes 
me feel good.

73 Tom

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