The prime directive on this reflector is to do exactly what the manufacturer
recommends…… however.
Many guys on this reflector put way more on a Rohn tower than specs would
suggest would work. Just look at the home pages of almost any of the big
mutli-multi and big contest ops on the web and you will see a lot more
aluminum up in the air than Rohn ever legitimized. This does not suggest
that you should be reckless, and if you put up a lot of aluminum, then you
want to make sure that everything else about the tower is done first class
(base, anchor points, guys, brackets, number of sets of guys etc. etc.
I was not a big abuser, but I had up a pair of stacked 20 meter 5 element
wide spaced yagis, one at 100’ and the other at 60’ (the bottom yagi was on
a very heavy duty custom swinging gate so it would rotate 300 degrees).
Above the top of the 20 meter stack I had a 2 element 40 meter yagi, and
near the top of the tower a 7 element 2 meter yagi side mounted, and down at
50 feet I had a Cushcraft A3S mounted to one leg of the tower.
That tower went through a lot of wind. I was located 70 miles north of the
Gulf of Mexico and took several good sized hurricanes that were still
whistling when they roared through Hattiesburg. I also had serious straight
line winds. The tower and antennas were solid. I underguyed this tower on
number of guy levels. I had only two sets of heavy duty guys on that tower (
at ~95’ and 50’) as I wanted to swing the big monobander around the tower on
a swing arm. The swing gate was just above the bottom set of guys.
What finally did bring down the tower was a tornado that passed directly
over my house and through my property, which felled three 70 – 80’ lob-lolly
(sp?) pine trees (I lost 38 trees in all) and all three came down hitting
one set of guys. When that happened, the pressure of the trees pulled the
guy wire through the guy clamps on one of the opposite side guys on the top
set of guys and that folded the Rohn 45 right in half, just above the bottom
set of guys and guy bracket. Bottom 50 feet of tower was fine. However, I
really had no complaints on the tower…. Not much would have stood up to 3
large pine trees hitting the guys just about simultaneously. Before the
tornado got me, my set up was up for a good 10 years and really PERFORMED.
My opinion is: watch what you do, think it through carefully, talk to some
experienced tower and antenna guys, surf the net carefully, and then put it
up.
73 Gary W5FI
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