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

The whole idea of the OCF is to moderate the wild excursions of impedance
that is so typical of a center fed antenna operated at even harmonics. I've
used both over the years (OCF and Center Fed). I prefer the OCF for general
use and the balanced fed dipole for best overall performance. I will say the
impedance excursions of the dipole were annoying (of course, one can always
employs Cecil's trick and avoid the problem completely). Cecil approach,
while effective, makes the entire project more and more complicated.

For a "throw it up and use it" approach, the coax fed OCF is hard to beat.
It works and presents impedances that are typically handled quite easily by
even the minimal tuners incorporated into many of today's radios. I use a
135' OCF and have no trouble matching it at all (it's a CW-80 Carolina
Windom). I have found its performance on 80/40/30 to be quite good.

....hasan, N0AN

"afcsman" wrote in message
...
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