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Old December 25th 07, 04:45 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Standing-Wave Current vs Traveling-Wave Current

Roger wrote:
Hmmm, Like Roy, I thought there was still a traveling wave in this
situation. The voltage at the far end of the line must reverse polarity
as time passes, so the waves must continue to travel, or so I would think.


It is common practice to divide the waves into standing waves
and traveling waves so they can be discussed separately. For
instance, if the forward voltage is 200 volts and the reflected
voltage is 100 volts, we have a mixture of standing waves and
traveling waves.

It is common practice to allocate 100 volts of the forward wave
to the standing wave in order to exactly match the reflected
voltage with the resultant *pure standing wave*.

The other 100 volts is allocated to the *pure traveling wave* that
is making its way from the source to the load. That's how my profs
at Texas A&M chose to teach the subject. It's a sort of reverse
superposition technique that makes everything crystal clear in
a system of mixed standing waves and traveling waves.

Is this a "tongue-in-cheek" comment?


You think? :-)

Note that in a pure standing wave, the magnitudes of the forward
wave and reflected wave are identical.
--
73, Cecil http://www.w5dxp.com