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Old September 5th 05, 10:27 PM
Walter Maxwell
 
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On Mon, 5 Sep 2005 15:31:18 -0500, (Richard
Harrison) wrote:

I appreciate Walt, W2DU`s kind words regarding my posting about ground
rods and radials.

I did not recommend any particular number or length of radials. RCA`s
Brown, Lewis, and Epstein examined how many and how long ground radials
should be in the 1930`s. The FCC accepted their experimental work,
conducted at 3 MHz, and used it to set ground system standards for
broadcasting in the medium wave band. These standards are still
applicable. B.L.&E. did good work.

Another RCA alumnus, E.A. Laport, abstracted some of B.L.&E.`s work in
"Radio Antenna Engineering". Figs. 2.17, 2.18, and 2.19 on pages 119 and
120 show field strength as a function of the number of radials. All the
Figs. show near perfection with 113 radials, so it seems the FCC rounded
up to 120 radials and made it the rule. It`s worked well, giving us
good broadcast reception when the earth is dry and sandy or wet and
swampy. Laport`s figures show performance with 1/2 and 1/4 the ideal
number of radials.

As Walter flattered me, I`ll reciprocate. Get hold of the April 1973
issue of QST. Look on page 35. Walter is pictured there. He is a real
good looking fellow!

Best regards, Richard Harrison, KB5WZI


Thank you, Richard, for considering me for the MAS (mutual admiration
society). You are too kind. The issue of QST you referenced contains
the first installment of my series of articles, "Another Look At
Reflections," which form the first seven chapters of 'Reflections 1
and 2'. Incidentally, the 3rd edition is in the publication stage. I
will be posting the release date on my web page at w2du.com.

Back on the subject of radials, unless the FCC has changed the
requirements since I was involved, the requirement is for 90 radials.
However, most of the AM BC stations I'm familiar with use 120, even
tho not required.

Walt, W2DU