On Thu, 30 Jul 2009 11:29:13 -0400, Doug Rehman wrote:
>3) No radials on the vertical (unless they're only about 18")
>4) It will be mounted to the wall of the elevator penthouse
>5) It can be tied into the perimeter lightning ground
Your 100 mph requirement without guying really limits the
possibilities. I would ask WNY no guying? If the objection is to
conductive guys that could cause problems, I would suggest a non-
conductive guy material like Phillystran, which is quite strong
and has very low visibility (it's black). Also, don't be afraid to
play the "homeland security" card.
For antenna hardware, I would look at DX Engineering -- their
hardware seems to be more robust than most, and their engineering
tends to be good. I would also try to limit the frequency coverage
to what you actually need. Anything you do to the antenna itself
to make it cover multiple bands is going make it less robust.
I'm assuming that the feedline will be relatively short (less than
100 ft). If so, I'd run RG8 to it and put up the tallest, most
robust aluminum that you can and tune it from the shack. Just make
sure that it's not close to a half wave on any band where it has
to work.
One positive thing though -- a low impedance bond of the coax
shield to the building steel and the lightning protection system
will serve quite well in place of radials.
73,
Jim K9YC
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