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[TowerTalk] Adding ground radials to Gladiators

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Subject: [TowerTalk] Adding ground radials to Gladiators
From: (Jim Reid)
Date: Tue, 28 Apr 1998 15:41:50 -1000
At 06:15 AM 4/23/98 +0000, you wrote:
>I pay just over 2 cents a foot for buss wire (in 5000 ft single 
>piece lengths on a reel), so it costs less than most troublesome 

Wire gage?

>By the way, I just made ANOTHER series of measurements on radials. 
>These are actual field strength measurements taken at various 
>distances with a 1/4 wl vertical in a clear flat open pasture, and 
>also compared that antenna on the air with other antennas.
>Four elevated radials were down ~1 dB from sixteen BARE wires 
>stapled to the earth, and 60 radials were about 4-5 dB better in all 
>The same results appeared in over the air tests, where listeners 
>reported the four radial vertical 5-10 dB down from other antennas. 
>When 60 radials were added, the difference disappeared.

Hi Tom,

I believe I am now convinced!  I now have seven monoband Gladiator
verticals up.  All are on Radio Shack push -up poles,  so the antenna
bottoms are up around 10 to 12 feet.  Four full length 1/4 wave,
elevated radials fan out at the base of each vertical.  You can
walk around under the radials near the poles.    The radials
for the 160 spread a loooong ways!  For the bands above 30 meters,
I was able to get the radials to slope away from the antenna bases
at about 45 degree angles  a la ground plane configuration.  However,
I am able to compare the higher bands,  to either "drooping dipoles"
(on 30 and 40M)  or my Mosley TA-34-XL  tribndr( four elements,  each
trapped,  21 foot boom).  On 160 and 80,  I can compare/contrast
the performance to my rather low 1200 foot long,  center fed
doublet!!      I have been using these with the FT-1000D
as antenna diversity signal rcv set up,  inputting the vertical in use
to the 1000's so called BPF-1 external rcv antenna input to VFO B.
Works well for CW stereo;  sometimes the signal to the ear
listening to the vertical channel is actually louder,  signal polarization
wandering about,  I suppose.

Anyway,  obviously the signal levels are lower from the verticals,
usually,  sometimes higher.  However,  from reading your inputs,
it seems I ought to go ahead and buy a reel of wire from Press
Jones,  The Wireman,  and start adding ground radials.  Would
the correct connection be to run the radials lying on the ground
up the side of the RS push up pole,  and tie them in common
with the elevated radials??  That is,  the vertical would have
both elevated radials,  and a bunch of ground mounted ones.
Perhaps ground mounted radials require that the base of the
vertical be down at ground level,  not up on a push-up pole.

Six of these Gladiator verticals are on the side of a hill just
behind my QTH,  and are all spaced around within about
a 75  foot or so diameter circle,  so radials do criss-cross;  though
none of the elevated radials touch one another;  however,  
obviously ground lying bare copper wire radials would be
bound to cross many radial wires running out from other
verticals.  Perhaps this would completely destroy the value
of adding ground radials to these rather close together
verticals.  But your report of picking up 4 or 5 dB with
60 ground radials would certainly be worth the effort.

Maybe the radials on the ground should  use insulated wire?

The ground here,  years ago was pineapple plantation;  soil is
several million year old decomposed volcano debris!
University of Hawaii Ag Dpt folks say the typical Kauai plantation
land soil conductivity is around 300 to 500 deci-Siemens/m.
I presume this translates to 3 to 5 mSm/m as usually measured
in our HF antenna language,  though not certain of that.  When
asked about it,  they said deci-S/m was the "new standard",

Anyway,  should you care to comment,  would appreciate
any input,  Tom.

Mahalo and 73,

Jim,  KH7M
On the Garden Island of Kauai

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