(changed the title from 17m..)
Again an excellent paper from Jim.
Had one quick read.
This is going to take days to digest and consider.
Although it is obvious to me that height is important, this is the first
time I have seen it quantified.
Vy gud.
My favorite line in the entire paper was:
"Don't let "great" become the enemy of "good"... (or something like that).
EXACTLY MY POINT on nearly all of the antennas I post on my web site.
Most of us will never have a great antenna, for a long list of reasons:
e.g., Space, Money, HOA, XYL, Neighbors, etc.
There are a lot of simple antennas that work and work well.
And there is no single one which will work best for most people.
Each of us must evaluate our own situation, under consideration of the
points above and determine what is going to work best for us.
BTW Jim, if you ever want to do an increment to the paper, I would be
interested in seeing how much difference rotating the dipole will make in
real life at various heights.
On the other hand, if you can manage to have two dipoles perpendicular to
each other, there is no need to rotate.
I have only ever had that once in my life and it was on 80m with both
dipoles 75 ft. high.
The results varied from no difference at all, to several S-Units.
We have a d-i-y add-on to our 3-band or 5-band wire Yagi antennas which
adds a short end-loaded 40m dipole to it, but rotated 90 degrees. It uses
the 20m director and reflector for capacity end-loading.
We have enough installations of this antenna in the field to conclude that
when compared to a fixed full-size wire dipole at a similar height, there is
no noticeable difference in most directions but in some directions
(presumably off the ends of the fixed dipole), the short dipole is several
S-Units stronger. We have never measured this with instruments, but
experience it every time we use the antenna.
It would be nice to see this quantified, so Jim if retirement life is boring
you a little, here's a little distraction for you! (hi)
Thanks for the paper and the link, Jim.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Brown
This link is to a slide show for a presentation I've done several times
about this set of issues. It doesn't address delta loops, but it does
compare horizontally and vertically polarized antennas at various mounting
heights.
http://k9yc.com/VertOrHorizontal-Slides.pdf
73, Jim K9YC
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