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Old November 1st 14, 08:44 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
Posts: 1,336
Default No antennae radiate all the power fed to them!

On Sat, 1 Nov 2014 15:26:52 -0000, "gareth"
wrote:

***** Without the remnants of non-radiated power, there could NOT be
a standing wave!


That's quite true. Standing waves require a transmission line. If
all the RF has been radiated, and there are no "remnants" left in the
transmission line, there can be no standing waves because there is no
RF.

Think about the other boundary conditions.

If you unplug the coax cable and antenna, and then transmit into an
open circuit, there are no standing waves. All the RF power is
converted to heat in the output stage. There's no transmission line
upon which to produce standing waves and there's no antenna to
radiate. Without a transmission line or antenna, there can be no
radiation and therefore, not standing waves.

The other extreme is also true. If you have an infinitely long
lossless coaxial cable, with either an open, short, or black hole at
the far end, there are no reflections because the wave will never
quite reach the open or short to produce a reflection. Without a
reflection, there can be no standing waves.



--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
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Skype: JeffLiebermann AE6KS 831-336-2558