In a message dated 98-12-26 01:03:41 EST, ni6w@yagistress.minden.nv.us writes:
> > In otherwords, does 15 sq foot rating assumes the antenna is at the top?
>
> For the Rohn configurations, Yes!
According to the Rohn engineer that I talked to, the rating is for the
WHOLE tower and is regardless of where the load is. Remember these towers are
designed/configured for commercial applications which many times means
antennas and dishes all up and down the tower. It's my understanding that the
capacity is more or less a constant.
I will always defer to your technical and engineering knowledge so am
obviously interested in your comments. A caveat: Rohn engineers and specs are
obviously meant to be useful to anyone so the specs have built-in engineering
overhead and have worse-cased potential configurations with their liability
and risk-exposure interests in mind. In other words, there is a good sized
"fudge factor" built in already for everyone's protection.
>
> > Distributing the loading differently could get you extra capability?
>
> In most cases, Yes.
I understand how this is possible but I think this requires you (Kurt or
any other installer) to make your own assumptions and calculations. This is
not a course I would suggest anyone undertake (pun intended). If you're not a
good engineer and can't do the calculations with a great deal of confidence, I
would recommend going with the factory specs and not trying to second guess
the manufacturers specs. (The LXC Prime Directive always applies - "DO what
the manufacturer says".)
Cheers, Steve K7LXC
Tower Tech
Champion Radio Products
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