>From one who has used baloon supported wires on 160 and
elsewhere: Forget the models, small differences are
meaningless. The antenna will seldom be vertical, due
to wind.
If it were me, I would make a full sized ground plane, with
4 radials, and have the baloon hoist that. Allow the radial
ends to rise to above ground 50' or so. The result would rise
to almost 300', and require a circle of over 250' to hoist.
You'll rapidly realize that the economics of lifting such a
bundle are unattractive. Which brings you back to hoisting
only the wire, and feeding it against ground. Now, you have
to put in a substantial ground system to be effective, and
the economics of the lifting package are STILL not appealing.
K2BMI and I fed 3/8 wave against the steel frame of the
chemistry building at Rutgers, one cq160 contest. It was
at 45 degrees most of the time.
The W1MOO field day group, in VT, contemplated a baloon supported
antenna a few years ago. I think we calculated we'd need over $100 of
helium to keep the thing up for a weekend, and abandoned the plan.
n2ea
jimjarvis@ieee.org
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See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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