Many thanks Bud.
I will need to review which version they are using. Yes I had someone pointing
me in the direction of a freestanding tower but I think I may go to using guys.
It's either that or trade my tower sections in on a stronger better built
freestanding tower designed for that purpose. I only need about 24 to 28 feet
in height. Maximum.
Best regards - Brian Carling
AF4K Crystals Co.
117 Sterling Pine St.
Sanford, FL 32773
Tel: +USA 321-262-5471
> On Feb 12, 2015, at 12:27 PM, W2RU - Bud Hippisley <W2RU@frontiernet.net>
> wrote:
>
>
>> On Feb 12, 2015, at 9:58 10AM, bcarling@cfl.rr.com wrote:
>> I am putting together a permit application with my city which requires
>> certfication for 139 mph
>> for three second gusts as in TI-222 spec. Also steady 100 or 110 mph I
>> think.
>> We are making a 30 foot Rohn 25G tower according to the Rohn specification
>> with 4 foot
>> cube base of concrete with no guys.
>
> I’m not sure I understand what you’re hoping to find.
>
> My 4-year old Rohn catalog makes it VERY clear that 30 feet of Rohn 25 can
> hold only 1.7 sq. ft. of added antenna when the environment is 90 mph
> (ANSI/EIA-222 Rev. E) and NO ICE. (For areas that experience icing, Rohn 25
> is specified by the manufacturer at ZERO sq. ft. of additional antenna load!)
> From your e-mail address and the wind speeds you mention, I’m going to guess
> you’re in Central Florida, and I daresay a 90-mph Rohn EIA-222 Rev. E
> specification is not going to be adequate for your city.
>
> Nowhere in your posting do you mention what total antenna, rotator, feedline,
> etc. wind surface area or wind load you anticipate putting on this tower.
> But my guess is that NO freestanding 30’ Rohn 25 tower is going to make the
> grade.
>
> Also, you fail to mention which version of TIA/EIA-222 your city is using.
> The latest I’m aware of is Rev. G — a substantial revision from previous
> methods of specifying wind loading.
>
> Bud, W2RU
>
>
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