In my UST documentation, the only numbers that have a PE's signature next
to them are the numbers given in the Engineering Specifications. For the
HDX-555 it's:
23.2 sq ft (350 lb wind load) at 1 ft above the tower.
70 mph basic wind speed
Max allowable antenna weight: 200 lbs
The 50 mph/30 sq ft number in the catalog appears to be a marketing
number. It also does not specify the height of the antenna above the
tower. As Steve eluded to, if you put 30 sq ft on one of these towers,
and you experience a 70 mph wind, you may need to call your insurance
agent. If you crank through the tower analysis you will find that this
tower will handle 30 sq ft at 1 ft above the tower at 60 mph peak wind
speed. So, it seems that the catalog is not misleading, just a bit vague.
Play it safe and use the Engineering Specs. and the wind loading for your
area.
73,
Frank W9JCC
On Thu, 02 May 2002 21:50:16 -0700 Kelly Johnson
<KellyJohnson@telocity.com> writes:
> US Tower catalogs state the 50 MPH ratings. If you buy the
> engineering specs
> they give you windloading specs for 50 AND 70 mph.
>
> K7LXC@aol.com wrote:
>
> > In a message dated 5/2/02 5:34:24 PM Pacific Daylight Time,
> ve6wz@shaw.ca
> > writes:
> >
> > > I have estimated the total windloading (14 sq ') of my antenna
> stack to be
> > > less than the max. recommended by US tower...this is a good
> thing.
> >
> > AT WHAT WINDSPEED? 50 MPH? In the US, the lowest rating is 70
> MPH so
> > according to the US Tower catalog NONE of them are rated correctly
> for ANY
> > real application.
> >
> > What's your local windspeed rating?
> >
> > Cheers,
> > Steve K7LXC
> > TOWER TECH
> > _______________________________________________
> > Towertalk mailing list
> > Towertalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
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