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TopBand: Inverted-L question

To: <topband@contesting.com>
Subject: TopBand: Inverted-L question
From: K1ZM@aol.com (K1ZM@aol.com)
Date: Fri, 27 Sep 1996 20:01:30 -0400
Hi Tom

I couldnt agree with you more.

I use over 1000 radials (some over 300 feet long) under my 160m systems and
the old adage "you don't get something for nothing" sure applies in the case
of 160M ground systems!

This is supplemented by 10 runs of 48" wide hardware cloth, each 50 feet
long, on top of the radials in order to ensure maximum ground screen within
the near field to the antenna's base where I believe most of the significant
current is.

Have you any info which confirms the significance of this near field current
effect Tom??

W1ZE (now a 160M SK)  taught me to believe in the hardware cloth as he used
copper plate under the ground in the first 50 feet of the near field under
his 70 foot top loaded 160m vertical up there in MASS.

I have to take alot of stock in this approach because it sure worked for him
and I think it is helping me improve my system as well.  What else does one
do after putting down 1000 radials on the ground?  Sure beats me!

I have stopped working on this radial stuff here unless someone can convince
me there is another way yet to improve the system.

BTW, I have tried some elevated GP 160m verticals with around 8 elevated
radials (resonant eg: 133 feet).  These run from around 20 feet at the
feedpoint down to around 3-4 feet at their ends.  Yes, these do work - how
well, i really cannot say.  But given the right type of real estate (eg:
enough of it) I would always go with PLENTY on the ground supplemented by
near field coverage with a screen, if possible.

I doubt if the screen improves the ground side of the antenna much after
about 250 radials, but the REFLECTED IMAGE PLANE under the antenna just has
to benefit BIG TIME by this approach.  

I also have such a system under development on CAPE COD within 300 feet of
the Atlantic Ocean.  When completed, I will be in a position to see what such
a system can really do under ideal circumstances.

Take care,  73
Jeff K1ZM@aol.com

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