CQK8DO@aol.com wrote:
> I have experimented with my 4 el M2 40 meter yagi... I have found that it
> seems to ride the quietest, i.e. the least amount of visible thrashing,
> bowing, jerking, torquing the tower, etc., when it is quartering to the
> wind... For non sailors, that means with the boom (the keel) at roughly a 45
> degree angle to the prevailing wind... It does not seem to matter which end
> {i.e. dir or ref} of the antenna is upwind... Now, I need to build a weather
> station and interface to the computer and the rotator to keep it that way as
> the low pressure system slides past and the wind shifts constantly....
>
> Cheers .... Denny
[Cooper, Stewart GM4AFF]
I agree with the 45deg men. It's not constant wind speed that destroys an
entenna, it's the sudden gusts. We get a lot of wind here, and boom at 0 deg
really lashes the elements around. Boom at 90 deg puts more (how much more??)
strain on the tower/stub, I suppose. Boom at 45 deg displays the least
thrashing and torquing. No theory, just watch it and fiddle with it! I have 4 x
144MHz yagis in a 12ft box on another tower. Lets have some suggestions for
minimising load/thrashing on that! (They sit best at 90 deg to the wind).
Stewart Cooper
GM4AFF
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