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Old October 3rd 06, 02:19 AM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 1,614
Default Where Does the Power Go?

Dave wrote:
the big confusion factor is using power and energy at all. they are both
derived from the much simpler to handle and understand voltage or current
waves.


But it is hard to answer the "Where does the power go?"
question without using power and energy. BTW, I didn't
start that question. Jon Bloom asked that question in a
Dec. 1994 QEX article as a rebuttal to the information
in "Reflections", by Walter Maxwell.

the biggest problem is that once you change from voltage or current
to power you lose the information necessary to calculate superposition
because you no longer have the phase information from the basic wave
components.


If one knows the length of the transmission line and the
velocity factor, the phases can be deduced. If one is
dealing with a Z0-match, which is most common in amateur
radio, the phase information is trivial because all the
voltages and all the currents are either in-phase or
180 degrees out of phase at the Z0-match point.
--
73, Cecil http://www.w5dxp.com