Date: Sat, 7 May 2016 19:47:29 -0500
From: "ve4xt@mymts.net" <ve4xt@mymts.net>
To: David Gilbert <xdavid@cis-broadband.com>
Cc: "towertalk@contesting.com" <towertalk@contesting.com>
Subject: Re: [TowerTalk] AN Wireless
Hi all,
It seems to me the question isn't if AN makes good towers or whether they spec
bulletproof bases. Clearly, they do. Dave is certainly to be congratulated for
a first-rate installation.
The question is whether an experienced, respected tower professional opining
the base may be overkill, or whether Trylon is good enough for the average ham,
rises to the level of defamation.
Does anyone think it does?
Difference of opinion does not equal defamation.
73, kelly, ve4xt
### LXC sez to follow the prime directive, do what the manufacturer sez to
do, including the base..and dont 2nd guess, and play...junior engineer, and
dont get involved with....
hip pocket engineering. AN uses a big base, why, cuz it’s a BIG, HEAVY tower,
that designed for a BIG windload. Those angle frame towers are not
streamlined, and the tower
itself presents a big windload, never mind the ants on top. Put 14 foot of
mast above the top of the tower, and you have almost effectively added another
section of tower to the mess.
Worse case is if the tower is loaded to its max windload rating, and you
experience extreme high winds some day. Do the maths, and the overturning
moment at the base of the
tower is extremely high. Think of a free standing tower as a giant torque
wrench, but with a big windload on the tower iteself, then add the load of the
ants on top. This is before you
add any ice to the mix. And some of the ants are not at the top of the tower,
they are as much as 14 ft above the top of the tower. Ever gone through a
75++ mph windstorm, and you will
wish you had twice as much concrete.
## I view it as a one shot deal, just use the prescribed amount of concrete,
and then some, to begin with...and use 4000-5000 psi strength, and lotsa
rebar. Pay once, cry once. You cant
add more concrete...after the fact, too late.
Sure, the trylon is good enough for the average ham..... but not when it cost
more than the AN, is far weaker, and NO pe stamp available. The light duty
trylon titan series windload ratings
drop like a rock, as the wind speed exceeds 70 mph. They are not ice rated,
nor earth quake rated. They were originally designed as a cheap, generic
tower, for the masses, for non critical
application use. They are not cheap anymore. They are not the big bang for
the buck they once were.
## Ok , if you want an angle framed tower, designed to handle winds up to 120
mph, huge windloads, and 1 inch of ice, seismic rated, and can have a PE stamp,
then trylon offers the real deal, in several
different formats, like their super titan series, ( which use just as much
concrete as the AN does, virtually identical concrete specs for a similar
width /height tower). The super titan uses 90 deg angle steel, that has been
bent in 15 degs on each side, part way out from the 90 deg corner...to achieve
the 60 deg angle. Rohn uses the same process on its 60 deg angled legs.
Available knocked down, or pre-assembled. Available up to 190 ft.
Trylon also now makes welded free standing towers, that use tubular legs and
solid round bracing. They come in 10 ft sections, and each section is heavy as
hell, check it out. Bottom section weighs > 1000 lbs alone,
decreasing as you move up to the smaller sections. Huge flange
plates..similar to rohn 65G, but bigger..and thicker. Now these welded
freestanding towers are also unique, they are streamlined, which increases
ant windload even more, since the windload on the tower itself is vastly
reduced vs the angle frame towers. They also come with several horizontal
7/8 inch solid rod climbing steps..on one face only. They look
like Z bracing on one face..and W bracing on the other two faces. The
climbing, horz 7/8 inch bars are welded between the tower legs.each one also
comes with a steel plate welded below each climbing rung,
to attach several heliax feedlines.....all the way up one face. They are
priced similar to the super titan towers, and will also handle 1 inch of ice
and 120 mph winds. Available up to 150 ft.
## The legs on both the AN + the light duty Trylon both consist of bent
plate..formed into a U shape, with a 60 deg angle. The AN uses stronger steel,
50 ksi vs 32 ksi, and a lot thicker legs.
Both use bent plate to make the braces, same deal again, the AN uses thicker
steel, and a lot stronger 50 ksi vs 30 ksi. AN forms the legs, punch the
holes, THEN hot dip galvanizes the
legs...ditto with the braces. Trylon shears the leg lengths from existing
galvanized steel sheets, then punchs the holes. End result on the trylon is
the edges of the legs have no zinc on em..and will rust, and
ditto with the punched leg and brace holes.
## So steve is wrong on both counts. I would not call it defamation by any
stretch. AN shouldnt be worried at all, they sell a superior product...for
less $$. Their independent Peng analysis of AN vs
Trylon tower sections proves that.
Jim VE7RF
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