Towertalk
[Top] [All Lists]

[TowerTalk] Re: Broadcast Tower Re-use

To: <towertalk@contesting.com>
Subject: [TowerTalk] Re: Broadcast Tower Re-use
From: K7LXC@aol.com (K7LXC@aol.com)
Date: Wed, 19 Feb 1997 19:49:10 -0500 (EST)
In a message dated 97-02-19 12:43:01 EST, aa6eg@tmx.com (Pat Barthelow)
writes:

>    We at the N6IJ contest station in Marina CA, have been
>offered a dismantled broadcast tower for use at our contest
>station.  It is 7 ea., 20 ft. sections of heavy steel triangular
>tower, 15" face width.  The vertical are 1 - 5/8" steel tubing,
>and the cross braces are only the horizontal type (no diagonals,
>like Rohn) but heavy, 1/4" thick, 2 inches wide, and spaced
>every 23".  At the top and bottom of each section, there are
>heavy, (3/8" thick) welded, triangular gusset plates/flanges at
>the inside of each corner, and are drilled to accept 3/4"
>assembly bolts.  The base has a conical ceramic insulator, which
>we may just choose to not use, and bury the first section in a
>poured concrete base.

Hi, guys --

     Please install with the base insulator in tact.  More hassle but much
more useful in loading up that mutha on 80 and 160M.
> 
>          Our wish is to use this at the site, guyed, at the full height,
>to mount a large Yagi Array.  We have a KLM-Derived, dual band
>Yagi,  3 element 40, 5 element 20 meter,  with a 56 foot boom
>for the top Yagi.  Perhaps rotate the whole tower/perhaps using
>a Tic-Ring Rotator for intermediate level yagis.  We inherited from
>the Ft. Ord military base large amounts of 5/16" ehs guy strand,
>still on new spools, and 10 ft. guy anchors, with steel
>expandable bottom fixtures. (Will these anchors with the expandable 
>fixtures (approx 12- 15" expanded diamater) be strong enough to anchor the 
>tower in compacted sand, or will we need to use concrete?) 

     I'd suggest using an equivalent Rohn tower and specs to give you an idea
what you need.  

     The surplus 5/16" EHS sounds grea if it's germane to your tower
installation.  The screw anchors don't.  If you know the geological soil
classification and soil holding power,  the screw-in anchors may be
okay...but I doubt it.  Loose fine sand and even coarse sand has little
"holding power".

>          The tower donor is a Crane company, (that took down the
>tower) owned by a newly licensed ham, who will offer to use his 110 ft
>crane to help assemble the tower.  We are looking for expertise
>in tower construction to advise us of pitfalls, safety issues, and
>structural capabilities of this tower.  We have large open areas
>on the top of a hill, (guying is no problem, space wise) and
>sandy soil.  We will hire a PE to do the design calcs, (obviously)
>but would like to have some idea of what this PE certification
>will cost, not having done this before.

     In 25 words or less??  This is a big topic with lots of things to take
into consideration.  Talk to W6EEN who is a PhD EE and PE for further
California info (w6een@ix.netcom.com).  

     The actual erection with  a crane (the best way to do it) is further
down the road until you get some of the  initial issues resolved.  

73,  Steve  K7LXC

    TOWER TECH -- professional tower supplies and services for amateurs


--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Sponsored by:             Akorn Access, Inc. & N4VJ / K4AAA

<Prev in Thread] Current Thread [Next in Thread>
  • [TowerTalk] Re: Broadcast Tower Re-use, K7LXC@aol.com <=