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Old December 24th 07, 02:38 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

Roy Lewallen wrote:
I stand by my statement that Z (the ratio of V to I) varies along a line
which has reflected waves.


What you say is true but it is important to note which
definition of "impedance", Z, that you are using. You
are using (1)(B) below, commonly referred to as the
"virtual impedance" definition because the R in the
R+jX impedance doesn't dissipate any power.

I don't think that you and Richard H. are using the same
definition of "impedance".

From the IEEE Dictionary:

"impedance -

(1)(A) The corresponding impedance function with p
replaced by jw in which w is real. Note: Definitions
(A) and (B) are equivalent.

(1)(B) The ratio of the phasor equivalent of a steady-
state sine wave voltage ... to the phasor equivalent
of a steady-state sine wave current ...

(1)(C) A physical device or combination of devices
whose impedance as defined in definition (A) or (B)
can be determined. Note: This sentence illustrates
the double use of the word impedance ... Definition
(C) is a second use of "impedance" and is independent
of definitions (A) and (B).
--
73, Cecil http://www.w5dxp.com