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Old May 4th 04, 03:29 PM
Crazy George
 
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Bill:

You need to enlist a little geometry and mechanical engineering. We like to
keep our top guys at 45 degrees or less (ground up to guy) where space
permits. The down force on the mast for each guy is then .707 of the guy
tension. As the guys get steeper, the down force on the mast becomes a
larger and larger portion of the total tension. So for a smaller
'footprint' with the guys near straight up, any side force on the guy from
wind or antenna tension becomes a larger down force on the mast. I need to
make drawings to clarify that point, so find someone mechanically inclined
to wave their hands and draw lines and make calculations for you.

As far as the stepladder on the roof, consider the average male is just
under 6' tall, with an 18" up reach. So he has to stand only 4 feet above
the mounting level of the base of the mast to erect it. A 5 foot stepladder
straddling the peak of most roofs is relatively stable if you are young,
limber and agile. Having the first (bottom) section SOLIDLY guyed is a
must. At least that's what I remember from the middle of the last century.

--
Crazy George
Remove N O and S P A M imbedded in return address
"zeno" wrote in message ...
Hi John,

For a 50' tall mast, what would you say would be the minimum acceptible

square
dimensions from vertices (on a flat plane with the base) of the guy wire

anchor
points?

Bill K6TAJ

John Moriarity wrote:

"zeno" wrote in message

...
How the heck did those TV crews of yesteryear erect 40+ foot
telescoping antenna masts sitting atop pointed roofs? Its not
exactly like you can set up a step ladder on such a roof to
get up the first 10 foot to pull up the rest of the sections.


That's exactly what we did! When you are
young and fearless and believe in your
personal immortality, it's amazing what
you can do ;-)

73, John - K6QQ




 
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