Cary,
I'd like to echo Malcom's congratulations and his
statement on your choice of station. You should
have lots of fun with it.
Steve, K7LXC, maxim to always "Do what the
manufacturer says" is definitely sound advice.
However, I'll offer an anecdotal tale of similar
installations.
I've used a Create Design roof top tower for
almost 20 years at three different locations. It
is about 7 ft tall -- had it so long I don't remember
exactly now. I use a 12 ft mast (it's just a pipe
which is another no-no according to the experts)
to support an A4S at the top. I also had an A3WS
up with the first two installations.
If you look in the ARRL handbook, several of the
earlier years' versions have it although I don't know
about the current one, it shows a bracing system
to using all-thread rod to fasten the roof top tower
to the joists(?) in the attic. I used that in all three
installations. It significantly increases the stability
of roof top towers.
I guyed the first two installations, but not the
third. The current tower base is about 12 feet,
high with the antenna at around 25 feet or so.
It's been up for 9 years and seen wind gusts in
excess of 70 mph with no problems. Being low
to the ground surrounding tree's about 50 ft or
so away help shelter the antenna from the
predominate wind directions of south and west.
I'm comfortable with my configuration as I live
in a rural setting and the only property that may
be damaged if something happens is my own. If
your planned installation will be higher, as in the
17 ft tower, I'd encourage you to guy it. It would
be a minimal expense for the added security.
Give some thought to how you intend to fasten the
guys to your house (or other structure) though. The
ARRL handbook offers advice on strengthening the
house structure for bracketed towers for example.
There will be tremendous forces at work with a
17 ft roof top tower and a mast with a yagi or two
even higher than that. You don't want to rip the side
of your house off and then lose your investment in
antenna's on top of that -- not to mention what would
be damaged if it all came down. Are you married?
If so, I'm sure the XYL wouldn't appreciate that!
Kevan Nason
K4LOX
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
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