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Old August 2nd 07, 01:51 AM posted to rec.radio.amateur.antenna
afcsman afcsman is offline
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First recorded activity by RadioBanter: Jun 2007
Posts: 63
Default Off-center fed dipole, fed with ladder line?

Rick (W-A-one-R-K-T) wrote:
On page 7-10 of the ARRL Antenna Book 20th Edition, there is a discussion
of "Off-Center-Fed Dipoles". It shows a dipole 130 feet long, fed 45.3
feet (a bit over 1/3 wavelength) from one end with a 4:1 balun, then coax
to the shack, and used on 80 thru 20.

I'm wondering if I can feed that with ladder line instead of coax and
balun.

It's not a "balanced" antenna (if there even is such a thing in the real
world) so maybe ladder line isn't a good choice here, but it would make
the installation a bit easier...

My experience with this antenna (fed with 300-ohm TV twinlead, which was
all I could afford at age 16) was electrifying. Using a DX-20
transmitter, I was able to draw nice sparks on 20 mtrs. You may want to
do some pruning to find a length that will keep RF out of the shack. My
own preference would be to center-feed the 130-foot flat-top with
ladder-line and use a link-coupled transmatch to work 80 through 10,
including WARC, and not worry about coax losses. You'll be the proud
owner of a "Zepp!"

73---W9NPI