Ken:
K0LR and I made some experiments to see what would be the 'preferred' or
'neutral' direction for antenna orientation during a strong wind. We did the
work back in April of 2002. What we found was a bit surprising so I wrote it
up in 2005 and it is on my web site. You can see the pictures and read the
text. We found that there was a difference when we oriented the elements
vertically rather than horizontally.
The write up is at
www.k0to.us/HAM/2Wind%20Torque%20Experiment%20-April%202002.mht
The pictures showing the experiments made with small yagi antennas have a
flag in the background that 'shows which way the wind is blowing'. Since the
flag is straight out from the pole it is obvious that the experiments were
done in a stiff wind.
The conclusion was that the boom should be normal to the wind for minimum
torque on the rotator. This is probably not the direction which places
'least wind stress' on the tower, however.
Tod, K0TO
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Ken Eigsti
> Sent: Thursday, May 13, 2010 9:04 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] STEPPIR and Wind Direction
>
> I just replaced a HAM IV that was turning my STEPPIR 3
> element with the 40/30 add on "trombone". (Brake broke) I am
> trying to figure out what direction to park the antenna (it's
> at a seldom used contest location) with regard to the wind?
> My C39 Force 12 yagi seems to like to be "pointing in the
> direction of the wind". If wind is from the west, it's pointed east.
>
> When the STEPPIR brake broke and started turning in the wind,
> I noticed that maybe it likes to have the wind blowing 90
> deg to which it is pointed.
> Wind from West, antenna pointed North.
>
> Has anyone else had some experience as to the direction of
> "least resistance" regarding the STEPPIR and wind?
>
> I thought there was a STEPPIR reflector but couldn't find it?
>
>
> Thanks
> Ken W0LSD
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