There are all sorts of metal and fiberglass telescoping poles available.
With guys, you really don't need much of a base. Carbon fiber is
overkill if weight isn't a big consideration. Guys can be Dacron rope.
You may need temporary guys on the first section and a step ladder to
get it up initially. Masts are fairly cheap and easy to put up, so I
wouldn't worry about making it survive a worst case storm. They also
won't do much damage if the fall down. Depending on the antenna at the
top, I wouldn't use the really tiny top sections.
I'm not sure what would happen to a fiberglass pole with a feedline
running down it in a lightning strike. It would probably depend on how
well the feedline was grounded. In any case, those masts aren't expensive.
I frequently use a 40 foot fiberglass mast for temporary operations. I
just set the base on the ground, with a tent stake to keep it from
moving sideways. I guy the first section with rope and tent stakes, then
push up the sections one at a time. I don't put additional guys on it,
but I don't use it in high winds. For a more permanent installation, or
a taller mast, I would add guys further up, as necessary. Probably even
up to 70 feet or so, sufficiently strong guys on the first section would
probably hold it up in light winds long enough to get it fully extended
and tighten the upper guys.
73,
Scott K9MA
On 2/16/2021 6:54 PM, Lux, Jim wrote:
On 2/16/21 4:18 PM, Michael Poteet wrote:
This is a request for opinions. I am thinking about putting up a wire
antenna. At my age (81) I have no interest in climbing towers, trees
or the
roof. Nor I am I interested in installing any support that requires a
concrete base or that weighs over 100 pounds.
I've noted there are at least a couple of telescoping masts (up to 50
feet)
that could be used to support simple wire antennas (when guyed
appropriately). One is carbon fiber, the other is aluminum. Is
there any
advantage of one of these over the other for "permanent" antenna
support?
Initial cost is not a factor.
I have one of the 40-ish foot carbon fiber collapsible poles. It's
fairly sturdy and easy to put up, but the top part *does* bend (it's
pretty small, think fishing rod tip).
The challenge is coming up with a way to support the bottom so it
stands vertically.
You don't want a big concrete base, which makes supporting a
challenge, to resist the overturning moment from wind loads and the
wire. With a 40 foot lever arm it doesn't take much force at the top
to have impressive forces at the bottom.
I've tried things like driving a 8 foot T-post about 5 feet in,
leaving 3 feet sticking up, and lashing a vertical to that. Aside
from the spectacular "trip hazard" of the T post, even with a tennis
ball on the top, it *will* bend or shift if the antenna is loaded.
And that's a fair amount of work to drive (my shoulders and back felt
it for days).
What kind of surface are you putting this mast up over? Grass? dirt?
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Scott K9MA
k9ma@sdellington.us
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