Rick Karlquist wrote:
> Bill wrote:
>> The following was Steve's question to me and my response which was snet
>> off the reflector.
>> Steve said:"Bill,
>> Are you an engineer? If so, can you devise a case, using a reasonable
>> tower and guy system, which contradicts my (and others) "theory"? I've
>> put this to a few engineers, and they haven't come up with one. I'd be
>> the first to shut up about it if an example could be shown...
> It is easy to imagine a guyed self supporter that is unsafe.
> Self supporters are strong at the bottom and weak at the top.
> If you guy a self supporter to allow a huge antenna to be placed
> at the top, the twisting force of the antenna will now overstress
> the top sections. This can bring down the tower even if bending
> moment etc is otherwise OK. You might be able to get away with
> this configuration if you counted on the mast to slip, and you had
> a breakaway coax link. You are still off the air, but at least
> the tower doesn't fall.
Another way to characterize a self supporter is to say that they are
strong at the top, and EXTREMELY strong at the base....
Of course hams tend to use the very weak ones :-)
At any rate, a "reasonable guy" system in your scenario just might
include a star bracket and double guys for the top set, but this is
getting way out of the "reasonable" range that I was thinking of.
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