[TowerTalk] Re: twinax
n7stu@vhfdx.com
n7stu@vhfdx.com
Tue, 30 May 2000 07:02:52
Hi Mark,
Unless there are other cables called twinax, what you describe is not the
twinax I am referring to. Twinax as I know it is a round cable about the
size of RG-8 with two ~18g stranded parrallel wires in a solid poly center
insulator covered by a braided shield. Basicly looks like a two wire RG-8
with smaller center conductors. I think I saw somewhere that the impedance
is 100 ohms, but don't know about power handling. I have only seen it used
as a data cable connecting midrange IBM systems.
At a minimum it would make good radial material. Could have some use as a
balanced feeder if the losses aren't to bad and it can handle legal limit.
Don't know if it would be worth the labor pulling it out of the attics and
conduits between buildings though.
At 09:35 AM 05/30/2000 EDT, Mark . wrote:
>
>Robert wrote:
><< It there any good use for twinax for antennas? We have miles of the
>stuff all over our wineries that has been decommissioned. Is it worth
>bringing home? >>
>
>Hi Rob,
>If I understand the term twinax, and you are referring to two coaxial
>cables, having separate shields and molded together in the same jacket, then
>the answer is yes, definitely!
>This can be used for shielded parallel transmission line, as described in
>the ARRL antenna handbook, and is my favorite way to bring parallel
>feedlines into the shack, straight to a tuner.
Definately a good use for that dual CATV distribution cable.
***N7STU is now KR7O***
73, Robert KR7O/YB2ARO, CM97xa/OI52ee (ex. N7STU)
n7stu@vhfdx.com
www.psnw.com/~n7stu (Norcal WSWSS activities & KR7O/YB2ARO homepages)
www.vhfdx.com/hscw.html (N. American High Speed CW Meteorscatter Contest
Info.)
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