One caveat - the RG-6 that is so plentiful and cheap these days has a
steel center-conductor with copper plating. This does not matter at
VHF/UHF where CATV stuff is carried due to the skin effect. However, I
have been warned against using this stuff for CCTV, where the composite
video is at a much lower frequency. I suspect that the skin effect
doesn't kick in with 160M RF enough for this stuff to be useful, but I
could be wrong. Also, I would be concerned about how much power RG-6
could carry.
73 & Good Luck,
Kevin
W4KBM
-----Original Message-----
From: topband-bounces@contesting.com
[mailto:topband-bounces@contesting.com] On Behalf Of Steve Ireland
Sent: Wednesday, July 02, 2003 5:03 AM
To: topband@contesting.com
Subject: Topband: Using RG-6 for 160m transmission purposes
G'day
Down here in Western Australia, RG-11A 75 ohm cable seems virtually
unobtainable these days - and VERY expensive on the rare occasions when
you
can get it. However, RG-6 75 ohm triple- or quad-screened cable is
cheap
and easy to come across, thanks to the growing number of cable TV
installations.
As a result, I am considering using RG-6 of this kind for an
transmitting
antenna project, but would like to know about:
1. Its (typical) velocity factor (have you every tried asking a TV cable
supplier what the velocity factor of a particular TV cable is?...)
2. What sort of power it can typically handle (the cable may have to
handle
something of a mismatch).
Any information direct to me would be much appreciated.
Vy 73,
Steve, VK6VZ
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