For completeness, when looking for guy wires that don't interfere with HF
antennas, you need to look at fiberglass guys as well.
In the quantity I used, they were cheaper than Phillistran and cheaper than
breaking up the guys with insulators every 11 feet (the ARRL number for no
ham-band resonances).
There is some detailed info on my website: www.erols.com/n3rr
BTW, Guy, what is your reference for the statement: "...ARRL anti-resonant
sections are a myth"? I had not heard anyone "complain" about this before
and capacitive coupling may be reduced to negligible by increasing the
length of an insulator. Far more commercial tower sites than hams use this
method.
73,
Bill, N3RR
----- Original Message -----
From: "Guy Olinger, K2AV" <k2av@contesting.com>
To: "tongaloa" <tongaloa@alltel.net>; <towertalk@contesting.com>
Sent: Monday, June 24, 2002 10:50 PM
Subject: Re: [Towertalk] Guy wire resonance. Break it up or use stubs?
> I've spent as much time as anyone worrying over guy wire resonances.
>
> The ARRL anti-resonant sections are a myth. They don't work because
> the guy wires are in the antenna near field and currents are NOT
> evenly induced across their length by a distant (far field) point
> source, apparently an unintended assumption in the ARRL figures. They
> further don't work due to capacitive feed across breakup insulators
> that changes the length in a non-predicted way similar to end-effect
> on dipoles.
>
> I'm not sure what construct you mean by transmission line sections.
>
> If you can afford it (do the comparative cost math on insulators,
> grips, etc) get Phillystran. Or maybe do the first 33 feet of every
> guy off the tower in Phillystran.
>
> Sleep at night.
>
> 73, Guy.
>
> ----- Original Message -----
> From: "tongaloa" <tongaloa@alltel.net>
> To: <towertalk@contesting.com>
> Sent: Monday, June 24, 2002 2:13 PM
> Subject: [Towertalk] Guy wire resonance. Break it up or use stubs?
>
>
> > What's the word these days on guy wires.
> > Break 'em up with insulators or make up transmission line sections
> to get
> > away from
> > resonance near operating freqs?
> > Thanks,
> > -bob
> >
> >
> > _______________________________________________
> > 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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