On 10/9/2014 3:50 PM, Lostgallifreyan wrote:
rickman wrote in :
Why would the wind tend to twist the ladder? Is your antenna highly
asymmetrical? I would be more concerned by the bending forces which can
be very high if the antenna is a considerable distance from the highest
guying point.
Even if the antenna were not symetrical, that bending would cause enough
assymetry to be bad. The only thin tall antenna mast I ever put up long term
was a receiving dipole for VHF, based on a thin angle-section scrap peice
from a a very long discarded shop front sign. It was as thin as a reed, and I
figured out that if I guyed it such that the flex above was countered by the
bowing below, then few gusts would ever cause it much risk. It twisted a lot,
but very gracefully, and despoite storm force widns it stood for fifteen
years until it rotted where it stood.
The wind never harmed it, but
corrosion eventually did.
I think you are getting confused. If the wind makes the antenna bend,
any asymmetry would be along the direction the wind is blowing and so
have no torsional force.
Or are you saying the antenna would bow of it's own weight? That is a
flimsy antenna. I think if you put this on top of a ladder you don't
need to worry about the ladder being the first thing to go.
--
Rick