No, you are correct as far as I know, Barry. But my gut feeling is if 90+
will take down 100' oak trees nearby (and it did), gust OR sustained, I
don't want to take any chances. Besides, how long is "sustained" compared to
a "gust"? We had 20-30 seconds of 90+ here last time we had this happen. Was
that a gust? In either case, if the tower isn't up to it (actually, the
tower probably isn't the question, it's the guy anchors and guys), it won't
matter, I guess. As I mentioned, the difference was less than $200 more to
build it to 110 mph vs. 80 mph. Heavier guys, bigger anchors. Compare that
cost to the $4K - $5K investment in the tower and antennas, and IMHO only an
optimistic moron (or an extremely cheap person) would design for the lower
speed in order to save a few dollars. On the other hand, if the person that
did that did it because of the money, he wouldn't have spent a bundle on a
new tower to start with - so that rules that out, leaving only the moron, I
guess. :-)
73, Jerry W5KP
----- Original Message -----
From: Barry <w2up@mindspring.com>
To: J. Kincade <w5kp@swbell.net>; <towertalk@contesting.com>
Sent: Tuesday, September 11, 2001 6:42 AM
Subject: Re: [TowerTalk] Paranoid vs. Overkill
> Correct me if I'm wrong, but the Rohn specs are for SUSTAINED
> wind speeds, not gusts. Big difference!
> Barry W2UP
>
> On 11 Sep 01, J. Kincade wrote:
>
> >
> > If my feeble memory serves me, I'm in an 80 Mph zone. In the past year
> > alone, we have had two occasions of officially recorded straight-line
blasts
> > of over 90 mph (recorded at the airport about 4 miles east of me). The
last
> > one took down a dozen or so very large trees around my place, and ripped
out
> > about 100 feet of split rail fence. So charts be damned, I built my
recently
> > erected guyed R45 to Rohn's 110 mph specs. Total added cost to get from
80
> > to 110, as far as I can figure, is about $75 worth of extra concrete,
some
> > extra sweat in digging larger anchor holes, and an added $100 or so more
to
> > buy 4130N mast material vice something a little more bendable. I'd go
for
> > the overkill on the wind speed rating, and give up a little tower height
to
> > do it if necessary. You'll sleep better at night, I promise.
> > 73, Jerry W5KP
> >
> > ----- Original Message -----
> > From: Gary B <blueis@sprintmail.com>
> > To: <TowerTalk@contesting.com>
> > Sent: Monday, September 10, 2001 11:50 AM
> > Subject: [TowerTalk] Paranoid vs. Overkill
> >
> >
> > >
> > > TowerTalkians...
> > >
> > > My question is simple. I live in a "70 mph" wind zone according to
what I
> > > can determine. Can I SAFELY use the 70 mph figure or should I build
in
> > > additional capacity by purchasing a stronger tower? Using a 'lower
spec'
> > > Trylon tower (eg, T400 vs. T600) means getting a taller tower at
> > > approximately the same price. (Remember: size does matter!) What
would
> > > you recommend? How reliable are the 'wind speed' tables? Do I stand
a
> > > *reasonable* chance of long service and no tower failure using the 70
mph
> > > figure? Or does this all boil down to how lucky I feel?!?
> > >
> > > The more I read, the less likely it is that I can make a decision!
> > >
> > > Tnx
> > >
> > > Gary B
> > > k3gb
> > > RVN BTO
> > >
> > >
> > >
> > > List Sponsored by AN Wireless: AN Wireless handles Rohn tower
systems,
> > > Trylon Titan towers, coax, hardline and more. Also check out our self
> > > supporting towers up to 96 feet for under $1500!!
> > http://www.anwireless.com
> > >
> > > -----
> > > FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> > > Submissions: towertalk@contesting.com
> > > Administrative requests: towertalk-REQUEST@contesting.com
> > > Problems: owner-towertalk@contesting.com
> > >
> > >
> >
> >
> >
> > List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> > Trylon Titan towers, coax, hardline and more. Also check out our self
> > supporting towers up to 100 feet for under $1500!!
http://www.anwireless.com
> >
> > -----
> > FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> > Submissions: towertalk@contesting.com
> > Administrative requests: towertalk-REQUEST@contesting.com
> > Problems: owner-towertalk@contesting.com
> >
>
>
> --
> Barry Kutner, W2UP Internet: w2up@mindspring.com
> Newtown, PA Frankford Radio Club
>
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
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