K6NA wrote:
> I think the answer is: When Rohn designed these towers they probably were
> looking exclusively at the "two-way" market, which in those long-ago days
> meant some kind of omni-whip or simple derivative.
>
> I seriously doubt any design engineer at Rohn ever contemplated a big
> ROTATING structure with significant distributed moment like a long-boom 20m
> yagi, let alone a full-size 40 or even 80m yagi. When was Rohn 45 designed?
> 40 years ago? I doubt there were five full-size 40m yagis in the world then.
Hi, Glenn,Thought we might hear from you on this one. These are good points and
I expect accurately describe the original design environment.
Everyone should understand that my comments are not an attempt to disparage the
Rohn Company or the original designers. let's face it, there are very many
successful applications of the Rohn tower sections out there.
I wanted to share some of my observations to expand the general knowledge about
the safe care & feeding of these things.
It's really useful to know and observe the maximum rev limits for the engine in
your car!
73, Kurt
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