Hi Rudy,
It certainly is possible to model that tower with all the antennas, at
least to a first approximation, if you take the time to do so. It's all
XYZ coordinates. The only aluminum that matters is what has a DC
connection to the tower, so insulated elements don't need to be modeled.
From your description, I'd say that tower is likely to be resonant
below 160M, which would make it an excellent reflector. My sloping
radiators are fed about 60 ft from my tower, and need only a bit of
inductive loading to resonate them. They are insulated from the tower by
a 10 ft piece of 4-in PVC conduit, so their top is about 5 ft from the
tower.
You'll need good radial systems to get the gain -- lots of radials for
the tower on the ground and at least four on the feedpoint of each of
the sloping wires. I have one sloping to about 70 degrees and one to
about 270 degrees. I feed them one at a time, with the other shorted. I
provide the short in the shack through a suitable length of feedline
(close to a half wave).
73, Jim K9YC
On 9/5/2017 6:12 PM, Rudy Bakalov via TowerTalk wrote:
I don't really know. Seriously, the tower itself is 90' BUT there is a KT36XA
at ~65', then 4 el 40m M2 at 90', and finally another KT36XA at about ~105'. I
don't think any model can properly factor in all this extra aluminum so I will
have to actually measure it.
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