Tom,
Thanks for the info. This is what I was looking for - info from someone who
has modeled the radials and/or actual experience with measurements.
Going over the wall simplifies things for me both for the shunt fed tower
for topband and for the radials for the 80M 4-sq.
I plan on soldering the radials together for both antennas wherever they
crisscross.
73,
N2TK, Tony
-----Original Message-----
From: Tom W8JI [mailto:w8ji@w8ji.com]
Sent: Thursday, September 13, 2012 11:27 AM
To: N2TK, Tony; 'topband'
Subject: Re: Topband: Radials over a stone wall
> Thanks for all the feedback on how to get the radials
> over/under/through the wall. After playing with this for the past few
> weeks I realize no way to go under as test poundings on rods indicates
> the wall is too deep.
Tony,
Sometimes things get lost in all the traffic on debatable topics.
You do realize there is very little disadvantage to just going up over the
wall and back down? It does not change the effective height any amount that
means anything, nor does it cause a shadow. It adds a little series
inductance, depending on the wavelength of the closed stub you form.
If you simply split the wire into two spread out wires far enough apart (a
few wall thickness apart) you cut the small series inductance in half.
It is often too easy and too common to forget the difference between
something we could ever notice even if we looked, and something that
actually matters. Usually as long as we don't do something wrong, many of
the things long discussions make sound worrisome are really insignificant.
I looked at the radials in a model, and the change on 160 from your wall
height and thickness was very minor, and could be made "very minor over N"
by adding multiple over-the-wall wires. You only added a ~3 degree long
stub.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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