Twisting isn't the issue ... bending is.
Look at it this way. Instead of yagis on the mast, picture blocks of
equal weight strapped to the same side of the mast. To extrapolate for
illustration, picture several weights spaced along the mast instead of
just two of them. With all the weights on one side of the mast it would
seem pretty obvious that the mast would bend in that direction. Now
alternate the weights on either side of the mast ... it more or less
balances the bending force on the mast.
73,
Dave AB7E
On 9/17/2023 11:14 AM, Chuck Dietz wrote:
If someone has a copy of or link to that article, I would like to read it.
The logic of it mystifies me.
I would think the Yagis, assuming they are pointing the same direction,
would put twisting torque and bending moments in the same direction no
matter which side of the mast they were attached to.
Chuck W5PR
On Sun, Sep 17, 2023 at 10:58 AM k7lxc--- via TowerTalk <
towertalk@contesting.com> wrote:
Any consensus on mounting two yagis on opposite sides of the mast?
YES. It is the preferred method. Dick Weber, K5IU, a Professional Engineer,
wrote an article for QEX some years ago that made it quite clear that that
was the way to go due to opposing vectors. Cheers,Steve K7LXCTOWER TECH
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