Mike,
I found a website with detailed info on the ZS6BKW antenna.
http://www.nc4fb.org/wordpress/zs6bkw-multi-band-antenna/
To use the antenna on 80M and above the 39.1 ft of ladderline should drop
down as vertically as possible, and then connect to 50 ohm coax through a
"1:1 current balun" (common mode choke). If you connect the station end of
the coax shield to center conductor and feed it against a radial system the
coax will be part of the "vertical element" of what has become a 160M top
loaded vertical fed against a radial system. How will the coax in your
installation run from the station to the base of the ladderline?
Or, if you have a 40 - 45 ft high support (tree) you might consider a W8AMZ
160M Reduced 1/2 Sloper.
http://w8amz.com/W8AMZ_SLOPERS_Page.html
If you do try the ZS6BKW antenna reconfigured as a top loaded vertical on
160M by connecting the station end of the coax shield to center conductor
fed against a radial system, I'd like to know how it works for you.
73,
Marsh, KA5M
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Mike
Smith VE9AA
Sent: Saturday, March 28, 2015 1:44 PM
To: topband@contesting.com
Subject: Topband: ZS6BKW
Thanks very much Marsh. Obviously you have some serious antenna modeling
skills and I do thank you for that second analysis.
If I may indulge you for one last request (tweak) pse?
If you could keep everything the same, but instead, leave the ladder line as
is and short the 50' of coax at the shack end (and add a normal 10' jumper
to the radio if it makes a difference?) would that make the #'s much
different?
Ground radials attached to the real 10' jumper /shorted coax interface,
right at the window. I think in actuality I am going to buy LM240 (is that
that right moniker for a RG8/x mini equivalent?) so I can sneak it out a
window, etc.
and if I was able to make the switch-over in the shack (or right at the
window-ledge) then that would be the way I go.
Thanks for the extra work. Hope we manage a QSO !
Mike VE9AA & ??#??? this summer.
p.s.-can't wait for snowmelt as I can start building and testing !
Mike, Coreen & Corey
Keswick Ridge, NB
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