How do you (generic "you") know what loads your roof will stand? How can
you be sure that a good strong wind -- 60mph, 80mph -- won't take the
antenna and the tower and a section of roof -- or the whole roof -- with it?
Alan NV8A
On 08/24/04 10:37 am W4ZW put fingers to keyboard and launched the
following message into cyberspace:
One often overlooked, inexpensive tower option is the roof mounted tower. I
use the Glen Martin 9' roof mount here and it is a great tower for less than
$400. My house is three stories on the ocean and the tower and elevation
above sea level gets me to the 80' level before I put on the mast. I have a
flat roof with a substantial deck built on it that is bolted into the steel
and concrete construction of the house. Only problem I have is the coupling
with the steel in the house when turning the antennas. I also use the Rohn
push-up masts. I have several of the 50 footers, one telescoped to 20'
that is used to hang either a full wave loop on 80 or a bi-square from the
top of the house. The other is only the first three sections fixed to the
elevator housing at three points with thrust bearings and a Ham-M at the
base. The sections are only partially extended to about 14' overall height
and supports a CC A4S.
These work very well and all have withstood microbursts off the gulf that
have exceeded 75 mph. I disassembled the yagis but left the booms up for
Hurricane Charley's winds, but the towers are still straight and secure.
Charley passed about 35 miles south of me here. If the Glen Martin 9'
model is properly installed, and the roof well waterproofed, it is a great
tower. I did have some problem initially with some drumming sound in the
third floor main room, but that was cured by using longer pieces of 2x6"
beams to spread the stress over the deck area.
I have a CC 402CD and a SteppIR on the Glen Martin. I have four A4S's that
I put up as the need arises on several of the Rohn push-up masts that I guy
with sailing Dyema line at three levels on the masts. The CC A3S and the
A4S are very good, lightweight, effective tribanders that are easy to
assemble and install. I do all my antenna tower work by myself and being
able to readily access the antennas and rotors is great.
Years ago, I had a short, sturdy rooftop tower on a two story house that
turned a TH-6DXX that also worked well.
YMMV,
Jon Hamlet, W4ZW
Casey Key Island, FL
"A little piece of paradise in the Gulf of Mexico"
_______________________________________________
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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_______________________________________________
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.
_______________________________________________
TowerTalk mailing list
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