[TowerTalk] Rohn 25G

[K7LXC@aol.com]

In a message dated 2/27/2006 9:02:09 A.M. Pacific Standard Time,  
towertalk-request at contesting.com writes:

>  I have purchased several sections of Rohn 25G - 3 straight  sections, and 
the 8' top section with rotor plate. I want to attach this to  the side of my 
two-story house, at two locations (top header board, and the  bottom board on 
the second story).  This is about 10' and 20' up from  grade.

>  What additional things do I need to purchase besides  the 10' piece that 
goes in the concrete; the house brackets; and a thrust  bearing for the mast - 
what else is required?


    Umm, any section can go in the ground. The  short-base is just 
half-a-section anyway. Just make sure there's 4-6" of sand  for drainage in the bottom. 
 
    Two housebrackets is per the manufacturer's specs  so you'll need them. 
Be sure to have a backing plate on the inside of the  housebracket to spread 
the forces out. 
 
    The only kicker might be that you're proposing  being 18 + feet  
including the concrete base section above the top  housebracket. Rohn specs only want 
you to go about 14 or so. I don't think  it's a fatal problem, just be sure to 
err on the conservative side in your  installation. 
 
>  Antennas planned are Hy-Gain TH3-MkIII, CC 505S, CC 215 and a  M2 432-9wl 
antenna....
 
    You really don't need a thrust bearing since your  rotator will be able 
to take any vertical load that you can put on 25G -  especially the ones below 
that you're proposing.  




Tony's, K1KP, article is a  real engineered house bracket installation 
including reinforcing the rafters so  you can see how involved it can be. 
 
Cheers,
Steve    K7LXC
TOWER TECH -
Professional tower services for amateurs
Cell: 206-890-4188