The balancing to which I referred (and which I should have defined) is wind
coming onto the Yagis broadside to the radiating elements, not broadside to the
boom.
73 de Gene Smar AD3F
Sent from my Radio Shack TRS-80 model 100 laptop
On Mon, Sep 18, 2023 at 1:21 PM, Chuck Dietz<w5prchuck@gmail.com> wrote: I
don’t understand the physics of how that works. If I imagine that I am
looking straight down from over the mast and I have a Yagi that has more
wind area in the front than the back, then it will exert a twisting force
on the mast trying to turn the mast to the left no matter which side of the
mast it is clamped to.
Chuck W5PR
On Mon, Sep 18, 2023 at 12:14 PM Gene Smar <ersmar@verizon.net> wrote:
> I believe the problem that's looking for a solution here is balancing the
> twisting torque imparted on the rotator, not bending moment exerted on the
> mast. Mounting hf Yagis on opposite or alternating sides of the mast will
> reduce the twisting torque versus having them on the same side.
>
> 73 de
> Gene Smar AD3F
>
>
> Sent from my Radio Shack TRS-80 model 100 laptop
>
> On Sun, Sep 17, 2023 at 8:33 PM, Stan Stockton
> <wa5rtg@gmail.com> wrote:
> Seems to me if you really believe mounting antennas on opposite sides of
> the mast is going to make a difference in whether the mast bends you
> already have a problem regardless of how you mount the antennas. I would
> think mounting the top antenna just a few inches lower would make more
> difference.
>
> 73…Stan, K5GO
>
> > On Sep 17, 2023, at 7:22 PM, Chuck Dietz <w5prchuck@gmail.com> wrote:
> >
> > Well my masts are very heavy. Weight of the antennas is not a real
> factor.
> > And saying someone is not an engineer doesn’t help either.
> > I believe It is a fact that the wind forces on Yagi antennas pointing in
> > the same direction are transmitted to the mast in the exact same manner
> > regardless of which side of the mast they are clamped to. It is a fallacy
> > to think that they would exert force in the opposite directions and
> cancel.
> >
> > Chuck W5PR
> >
> > On Sun, Sep 17, 2023 at 4:03 PM <k7lxc@aol.com> wrote:
> >
> >>> They were minimizing eccentric loads off the vertical centerline by
> >> putting one on either side. It won't do anything for reducing turning
> >> torque or wind loading, of course.
> >>
> >> Looks like you're not a Professional Engineer.
> >>
> >> Cheers,
> >> Steve K7LXC
> >> TOWER TECH
> >>
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