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Old July 2nd 08, 06:10 PM posted to rec.radio.amateur.antenna
Walter Maxwell Walter Maxwell is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 233
Default Open Wire fed lengths


"Dave" wrote in message news:vNMak.174$P11.105@trndny06...

"Ron Walters" wrote in message
t.net...
After reading several articles both on and off the WEB regarding a
center fed antenna, only one article mentioned a recommended length for
the feed line.


some antennas, like the g5rv rely on a particular length of feedline because
it becomes part of the antenna and radiates on certain bands. others use it
as an impedance transformer.


It is also a myth that the feedline for the g5rv requires a particular length
because it becomes part of the antenna and radiates on certain bands. At the
antenna terminals the feedline becomes a transmission line with opposite
directions of current on each conductor. Thus the fields developed around each
conductor cancel resulting in no radiation from the feedline if it's dressed at
90° from the antenna.

In addition, it's also a myth that the feedline of a shortened antenna radiates.
Some believe that the portion of the feedline that makes up for the missing
length of the shortened antenna radiates--tain't so.

Walt, W2DU