I am a ladder line convert. I use 600 ohm open wire feed, not really ladder
line technically, but the same scheme.
I was a coax only ham until about 2 years ago. Parallel wire feed to me was
too weird--i didn't believe it could really work. what changed my mind was
kirk klindschmidt's QST article, A Balanced Everyday Approach to All Band
Bliss. I believe this article affected many hams because since it has been
published in 2002 i think, we have a bunch of balanced tuners appearing on
the market. he referenced other articles, like the Lure of the Ladder
Line, and the Loop Skywire. I read all of them and became convinced this
was the way to go to get a wire up for 80 m. on my 50 x 100 foot lot. I
put up a cloud burning horizontal loop and fed it with balanced feed and
balanced tuner. the feed seemed magical. i had a gap titan before on 75
m. then went to an 88' center zepp with the ladder line for 75. it was 10
db better than the gap. then i went to the loop. it was 15 db better than
the 88' center fed flattop.
the two great things about balanced ants and feed is A. it is still pretty
low loss below the ant.'s resonant freq., and B. the balanced feed (to my
thinking) sort of brings the ant. feedpoint to you since it is part of a
symmetrical system. when you tune the matching network between ur || feed
and coax, it is almost like you are tuning at the feedpoint, the feed is so
low loss, high vel. factor, and it with the ant. make a dual component
symmetrical bal. system. this is why shortwave broadcasters use parallel
wire feed to their curtains--it is the only way to use a single antenna and
feed and be able to efficiently qsy to multiple bands to take advantage of
varying propagation condx, and run QRO without a meltdown and high loss.
sorry if this is hard to read--am in a hurry this weekend,
73
rob/k5uj
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