Thanks for your reply Steve. See comments and more questions
intersperced below. N4KG
On Sat, 22 Aug 1998 23:42 "Steven H. Sawyers n0yvy"
<sawyers@inav.net> writes:
>By the time the tower rotates far enough to have the torque arms
>do any good you have already used up most of the allowable lattice
>strength. Commercial installations don't use "torque arms" as hams
>do, they use things like the TA25 Torque Arm Stabilizer to get 6 guys
>to 3 anchors. Only the ones they use fasten onto the tower a lot
>better than the TA25 does and have more iron in them.
>
OK, I can follow that, but what if a base plate and pier
pin is used to allow the bottom of the tower to rotate
to accomodate the twisting movement?
It has taken a long time, but I have finally come to
appreciate that a rigidly mounted base is not a
good thing, especially if side mounted antennas
are installed, adding greatly to the torsional load.
Still, I cannot help but recall that towers with
torque arms FEEL more rigid when climbing.
Is this an illusion? de Tom N4KG
>Lots of commercial installations have 8 and 12 foot dishes side
>mounted
>to a tower, but they use the six guys to take up the torsional load
>and not feed it into the whole tower length.
Yes, I have seen some of those. NO question,
they will handle a LOT more torsion than a single
guy with a torque arm.
Your revelation that guy wire strength is the limiting
factor for towers of 100 ft or less is enlightening.
Rather than going up a step in guy wire size, would
using a torque arm stabilizer and 6 guys at the top
be a viable alternative or would the torsional loads
require heavier cable as well?
Final questions, I ASSUME that a guy bracket,
with or without torque arms, is a better / stronger /
safer way of attaching guys than looping around
a tower leg. Correct? IF one does loop a tower leg,
is it better to include the corners of the Z bracing in
the loop? de Tom N4KG
>
>de n0yvy steve
>
>At 06:45 PM 8/22/98 -0600, T A RUSSELL wrote:
>>
>>On Fri, 21 Aug 1998 22:46 "Steven H. Sawyers n0yvy"
><sawyers@inav.net>>writes:
>>>
>>>At 10:14 PM 8/21/98, Lee wrote:
>>>>
>>>>Why no torque arms?
>>>
>>>They don't do any good and are a waste of time and money.
>>>
>>>de n0yvy steve
>>>
>>Steve,
>>
>>I am confused by this response. How did you come to this
>>conclusion? Kindly provide your evidence.
>>
>>I invite you to climb 120 ft of Rohn 25 guyed WITHOUT torque arms
>>and then climb 120 ft of R25 WITH torque arms and tell me there is
>>NO DIFFERENCE. I don't buy it. Anyone else have an opinion?
>>
>>de Tom N4KG
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