I would just bypass the whole guy wire question. Get some high strength
copperweld and some strong insulators and put a couple of slopers down away
from the power line. gets you more antennas and some fall protection as
well.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Jim Lux
> Sent: Saturday, April 09, 2005 13:23
> To: Steve Maki; towertalk
> Subject: Re: [TowerTalk] Guying a self-supporting tower - NO
>
> > Since this has been discussed extensively before, I hesitate to
> > ask this....
> >
> > But I would really like to see an example (with a little analysis)
> > of a self support structure of ANY kind that is compromised by
> > sensible guy wires. By "sensible" I mean guy angles that are not
> > steep, and guy strand that is sized for the structure *top*, and
> > pre-tensioned at normal values. I'm really curious about this. I've
> > seen lot's of pronouncements, but little substance to support the
> > idea that self support structures should never be guyed. I fully
> > understand that some might be wary of the issues because of the
> > idea that encouraging overloading of towers might result, but this
> > is an interesting topic, academically.
>
> I think there has been some examples posted in the last couple years..
>
> Off hand, here's the problem I would contemplate: Increased down force
> from
> the guy tension will increase the compressive load at the base. Whether
> it's a problem is another issue. A self supporting tower will be
> generally
> stronger than a guyed tower of the same height (because it has to support
> the bending loads, which manifest themselves as compressive loads at the
> base). When you guy, you're turning some of the bending moment into a
> tension in the guy.
>
> There might also be some weird dynamic/vibration effects that you'd need
> to
> take into account.
>
> There's also the possibility (suggested by Rick Karlquist) that the guy
> serves merely as a "collapse restraint" to keep it from falling in a
> particular direction, in which case the guy is no different than a piece
> of
> coax hanging from the tower.
>
> >
> > For the purpose of illustration, it might be reasonable to take a
> > parameter to the the extreme, to see where the fault line is. For
> > the life of me, I can't imagine what it is.
> >
> > Steve K8LX
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any
> questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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