Bob,
I am in no way a expert on this nor an engineer but I do easily have 25 sq
ft. of antenna (5el 20m monobander on a 48' boom and a 9 el 6m monobander on
a 35' boom) on my 80' Rohn 45 and haven't had a problem with it yet. I have
two sets of elevated guys attached to 8" 10lb. I-beam 5 foot in the ground.
The attachment point is around 6' above ground so that I can mow underneath
and not have to worry about running into the guy wire. I've reveived winds
up to 60-70mph and it's rock solid.
Just my .02
73 Matt
W5LL
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of ROBERT CARROLL
Sent: Sunday, August 28, 2005 8:05 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Your Opinion on Rohn 45 and Monster SteppIR
I am on track to take delivery of a Monster SteppIR in mid-September and am
at crunch time as to which tower to put up to support it. The Monster has a
wind cross section of about 25 sq ft. The tower will be 70' in the Atlanta,
GA area. I have narrowed the tower choices to guyed Rohn 45 or Rohn 55,
guyed. Though several folks have suggested I have not looked in the right
spot, a look at my Rohn documentation seems to point to a wind load
capability of about 15 sq feet, with some verbiage about wind loading on 3
side arms assumed to be about 8 sq feet. It's not clear to me that you can
simply add 15 and 8 and conclude the 45 could be rated at 23 sq feet or so.
Several folks have said that with three sets of guys, the Rohn 45 will on
paper carry the Monster, but I have not been able to find anything to that
effect in the information I have. Several knowledgeable and experienced
DXers and contesters have assured me that Rohn 45 will safely handle the
Monster based on their experience and their knowledge of other
installations.
Rohn 55 is rated to handle 25 sq feet, but it is more expensive and harder
to handle.
I would appreciate input on the 45 versus 55 issue for this antenna, and if
in fact I have overlooked material stating the Rohn 45 will handle more than
about 15 sq ft I would appreciate your steering me to that information.
Bob W2WG
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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TowerTalk mailing list
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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