Maybe yo could look in to the HB9CV antenna instead. The dimensions should
be about the same but with a lot better match. A fast search showed an
antenna with a 75 ohms input and I remember several hams in Sweden building
that antenna with a 50 ohms input impedance.
_http://www.google.com/imgres?imgurl=http://www.radiosparks.com/images_d/Hb9
cv.gif&imgrefurl=http://www.radiosparks.com/schematics.asp%3FUID%3DAntenna%2
6newwindow%3Dtrue&h=480&w=640&sz=8&tbnid=GhQRdr7FeeDNRM:&tbnh=90&tbnw=120&zo
om=1&docid=wOUiIrOPETZBfM&hl=en&sa=X&ei=8CdNT5uYHefX0QGgh-W9Ag&ved=0CDIQ9QEw
Aw&dur=92_
(http://www.google.com/imgres?imgurl=http://www.radiosparks.com/images_d/Hb9cv.gif&imgrefurl=http://www.radiosparks.com/schematics.asp?UID=An
tenna&newwindow=true&h=480&w=640&sz=8&tbnid=GhQRdr7FeeDNRM:&tbnh=90&tbnw=120
&zoom=1&docid=wOUiIrOPETZBfM&hl=en&sa=X&ei=8CdNT5uYHefX0QGgh-W9Ag&ved=0CDIQ9
QEwAw&dur=92)
Hans - N2JFS/SM6BXX
____________________________________
From: w9ac@arrl.net
To: towertalk@contesting.com
Sent: 2/28/2012 2:05:16 P.M. Eastern Standard Time
Subj: Re: [TowerTalk] balanced line loss on a mismatched antenna
>"You'd be way better off with just a dipole (EZNEC says 22 - j600 ohms
for a 44 foot element) and either..."
I agree with Dave's loss numbers for 44 ft element length.
However, before giving up and using a shortened 44 ft. dipole, you may
want to see if there's a way get the elements lengthened close to a halfwave
and still keep spacing at 0.1 wavelength. Perhaps bring the ends down if
you're maxed-out on horizontal space. If you can, then you can use my prior
message as a guide for system loss. I would still model it with the
hanging ends. Otherwise, the 44 ft length on 40m is going to be a real looser
with the 8KJ as the added element really drives the impedance down from
mutual coupling and the short element length makes it too reactive to keep
losses low, even when trying to match at the feedpoint.
Paul, W9AC
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