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Old August 4th 08, 07:02 PM posted to rec.radio.amateur.antenna
Jim Lux Jim Lux is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default Telescopic aluminum question

Ed wrote:
I am considering putting up a ground mounted vertical antenna, based
on using telescopic aluminum tubing such as is available from Texas
Towers or DX Engineering. Tubing available ranges from .500 inch to
2.125" with corresponding increase in price as diameters increase.

My vertical should be limited to a maximum of 30 feet, but preferrably
around 23 - 25 feet. I will feed it with an SGC coupler at the base and
operate 80M - 10M.

My question: Using the 6' long aluminum pieces, what is the minimum
diameter sizes I should start with to enable the antenna stand up to a
75mph wind UN-GUYED. Also, how much "overlap" should I use in the
telescoping pieces?



How much flex do you want to allow? You can make it pretty small, if you
don't mind it bending a LOT in the wind.

Are you constrained to aluminum? i.e. what about a 15-20 foot length of
chainlink fence top rail ( aka galvanized pipe) with a standard mobile
whip on top. If you're worried about conductivity, run some copper wire
or a stripe of copper tape up the side.