Can someone quantify the value in db in either angle of radiation,
forward gain or other significant factors when a tri-band beam at 100ft
is retro-fitted from guy wires which are not broken up with insulators
to one using Phillystran? Or put another way. If I had a 100ft
self-supporting tower with a tri-band beam and compared forward gain,
angle of radiation, etc. it to the same antenna a 100ft tower guyed with
steel cable and no insulators, what would be the most significant, i.e.
noticable difference?
Is this another DXer fanatical .5db at 30 degrees does make a
significant difference debate?
What am I going to here on my ICOM pro or FT1000D if I don't video tape
the "S" meter movements and play them back for comparison? Am I going
hear a significant difference?
Is this another one of those bigs boys with their big toys and big $$
trying to over engineer an "amateur" antenna installation because there
just isn't much left for them to accomplish in the hobby?
Is this one of those, if I spend $5,000 on Phillystran I'll hear the DX
station 45 seconds sooner than my buddy down the road who is using
steel guy wires?
Curious minds want to know!!
73s
dave
wa3gin
Guy Olinger, K2AV wrote:
>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
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>
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