Donna,
I would consider the USTower heavy duty series of crankup towers.
(an example is below)
I would definitely go with a crank up tower vs a guyed tower in your
situation.
With a crank up tower you can lower it down partially during high wind
periods or leave it normally partially
retracted as I do. With the overlap increase even with a partial
retraction the wind load capacity goes up
exponentially. I have a USTower HDX589 and it usually resides at 75%
of its maximum height. This way there
is a huge increase in wind load capacity, much more than the towers
rating at full extended height.
When wind is not bad and there is a new DX station on I need, it only
takes a minute to extend it up to full height.
You do not have this flexibility with a guyed tower. This arrangement
give me about 70 feet antenna height normally which works very well and
about 95 feet if needed. I rarely raise it all the way up. Usually it
is when chasing an all time new country and it's probably unlikely the
added height really helps,
but it makes me feel better :-)
Also its not just about the tower. In a severe wind situation, the
antennas also fare much better at lower height. About a year ago we had
a storm with very high winds and the elements on my yagis were pushed
way back from the wind in almost a u shape. I lowered the tower all the
way in this storm so the yagis were up only about 35 feet.
Another thing to think about in a high wind area is the raising and
lowering system. You can get telescoping towers with a winch that only
raises the tower. When retracting, the take up drum simply goes in
reverse and rolls up the cable from the weight of the tower as its
coming down. This works fine except when in very high winds.
In high winds the lateral force on the tower sections can (and will)
prevent the tower from coming down. The cable becomes slack ! I had
this situation years ago with a tower. I came home from work and the
winds were very high. I ran out to the tower to lower it down (yes I
should have left it not fully extended :-) and tried lowering it. It
wouldn't come down ! I was helpless. The cable was slack. I finally
was able to lower it by tiny increments, the tower would jump down a
tad, then I would hit the winch a little and wait for another jump dowm,
you get the idea ! It took quite a while.......... BTW I have no
affiliation with USTowers, hihi. The thing to do is to get a tower that
not only pulls up the sections but pulls down also. The USTower raising
and lowering systems on their HDX towers use a take a drum and pulls in
both directions when raising or lowering. No more stuck tower when in
high winds, it pulls down too.
here is the HDX689 model:
http://www.hamradio.com/detail.cfm?pid=H0-002312
73,
Bob
K6UJ
On 10/30/16 10:33 AM, Donna Hinshaw wrote:
Hi all - Seems that I live in a beautiful but dangerous (according to
engineers who approve towers) place. My County adheres to the Rev. G of
TIA standards. I want to put up a Class I tower (typical ham use) but am in
a Category D QTH. So... what is the source of all those towers we see on
mountain tops? Which obviously withstand high winds? FYI - the AN
Wireless HHD series is not sufficient for my QTH for more than about 5 sq
ft of windload at a measy 50 feet. Not that it is a bad tower, just high
winds are POSSIBLE here.
Any pointers to sources will be appreciated.
----
Donna Hinshaw
AG6V
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