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[TowerTalk] AN Wireless

To: <towertalk@contesting.com>
Subject: [TowerTalk] AN Wireless
From: "Jim Thomson" <jim.thom@telus.net>
Date: Mon, 9 May 2016 07:39:30 -0700
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
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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