Scott, have you measured the self-resonant frequency of your tower
with beams on top? If it's anywhere close to 1.8, it will drastically
affect the feedpoint of the L as you show it.
Without knowing the tower's self-resonant frequency, it's going to be
very hard to anticipate the feedpoint Z of the L. You may want to
consider just loading the tower with one of the wire gamma match
arrangements to be found in the various antenna books. Given the
tower's thickness, and all the beams on top, you may not need the L
for anything.
I would estimate you couldn't put an L anywhere on your property
without the tower modifying the L impedance and/or pattern.
73, Guy
On Wed, 02 Dec 1998 04:12:33 -0600, Scott Neader KA9FOX
<neader@QTH.com> wrote:
>
>I have a small city lot with a single 72 foot self supporting tower. I
>would like to get on 160m mainly for domestic contests, but also to play
>with some DXing.
...snip...
Guy L. Olinger
k2av@qsl.net
Apex, NC, USA
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