----- Original Message -----
From: "Gedas" <w8bya@mchsi.com>
To: <towertalk@contesting.com>
Sent: Friday, December 23, 2005 10:45 AM
Subject: Re: [TowerTalk] guy wire resonance
> Dave, this is good advice and a good place to start but I seem to remember
> an interesting analysis Beezley did with an early version on MN many years
> ago. I think he was using MN but I might be wrong. He did an analysis of
> the f/b and gain of some HF yagi on a tower using the guy wire
> recommendations given in the ARRL antenna book. The pattern and f/b were
> effectively altered in a negative way. I think it might be a good idea to
> start with those recommendations but to model the actual lengths to be
> sure.
I've always used 3', 6', 9', 9', 10', and 20' the rest of the way. For
steel guys I always keep the conductve part short close to the antenna.
With the steep top guys which seem to have less effect I quit worrying
about the length after about 40'. Whether the antennas worked because of, or
inspite of the lengths I used, I don't know. they are different than the
lengths in the hand book.
Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com
> 73,
> Gedas
>
> e-mail w8bya@mchsi.com
> online gallery http://gedas.cc
> web page http://www.w8bya.com
>
> ----- Original Message -----
> From: "Frederick M. Mott" <ab8ah@earthlink.net>
> To: "'Dave'" <k4em@mindspring.com>; <towertalk@contesting.com>
> Sent: Friday, December 23, 2005 10:03 AM
> Subject: Re: [TowerTalk] guy wire resonance
>
>
> Look in the ARRL Handbook, chapter 30 of the 2004 handbook has a table
> called "Guy Wire Lengths to Avoid". I am sure this table can be found in
> the older or newer versions of the ARRL Handbook. Fred
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Dave
> Sent: Friday, December 23, 2005 8:17 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] guy wire resonance
>
> I am replacing some guy wires on a 70' Rohn 25 with a 40m beam. What is
> the
> spacing between the insulators so the guys are not resonant? The guys are
> 3/16" EHS and I am using the 500D insulators. I lost 3 guys due to ice
> storm
> last week, the Phillystran was cut in half on the top 2 guys but the
> bottom
> guy with all steel cable was undamaged. It was the 4000lb Phillystran.
>
> Dave
> _______________________________________________
>
> 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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>
>
> _______________________________________________
>
> 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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