Mike,
Please explain how you arrived at your 14.4 sq ft figure for this tower
configuration. Based on the information at:
http://www.rohnnet.net/rohnnet2001/catalog/pdfs/25G/25G-7.pdf
the answer is 8.7 sq ft, assuming round antenna members. The 45G guy tables
have additional sq ft taken into consideration for antenna supports, beacons,
etc. as referenced in the "Notes" section of the guy drawings:
http://www.rohnnet.net/rohnnet2001/catalog/pdfs/45G/45G-9.pdf
but no such assumptions appear in the 25G drawings.
Brad: My recommendation to you is to replace your 25G tower with 45G and stick
to the drawings' limitations.
regards,
Mahlon - K4OQ
From: Michael Pfeuffer <wq5c@texas.net>
Date: 2004/06/14 Mon PM 03:25:10 EDT
To: "Brad Hedges" <bhedges@nc.rr.com>
CC: towertalk@contesting.com
Subject: Re: [TowerTalk] Rohn 25 - how many beams?
Hi Brad,
Take a look at the Rohn engineering docs on their web site. The "guy
details" pages list the maximum windload for each configuration. At the
top of each diagram is two numbers one in an oval the other is in a
rectangle. The oval indicates the rated windload for round members, while
the rectangle is for flat members. For example, a 120' of 25G in a 90MPH
area is rated at 14.4 sqft.
GL,
--Mike WQ5C
At 01:21 PM 6/14/2004, Brad Hedges wrote:
>I'm planning on upping my Rohn 25G to about 115 ft this summer (from 45 ft),
>and I'd like to stack as many beams as I can, up to five, if possible (HF).
>
>I intend to guy every 30 ft, +/-, and only the top two - either a KT-34A or
>a TH7-DXX, and a HyGaine 2L 40M - would rotate. The plan being to fix
>additional tri-banders on JA at ~90 ft, on EU at ~70, and on SA at ~50 ft.
>Phase fed through a pair of WX0B Stackmatches.
>
>Is this possible? or should I just accept as fact that it is too much load,
>and find a heavier tower (I've got my eye on !00 ft each of Rohn 45G and
>AB-105)?
>
>I live in central N.Carolina - I'm Army, stationed at Ft. Bragg - and the
>soil is mostly sand over clay. Wind rating is 80 MPH. Where can I find guy
>anchor recommendations? Anybody able to help me here?
>
>Thanks,
>
>Brad
>K0BHC
_______________________________________________
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