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What is Pfwd and Pref with Complex Zo?
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September 10th 03, 03:57 AM
Walter Maxwell
Posts: n/a
On 6 Sep 2003 22:21:19 -0700,
(Dr. Slick) wrote:
wrote in message ...
But, going back to the original question, wbat is Pfwd and Prev on a
line
with complex Z0?
...Keith
I'd like to know the answer to this question too!
If we are talking about only DISSIPATED power, do we have
to say P=Vrms**2/Re(Zo)? Taking only the real part of the Zo?
And if phase doesn't mean anything for power, how can we use a
complex Zo in the denominator?
And if the Pfrd originates in Zo, Prev is loaded by Zo,
then even if Zo is complex, can you still not say:
[rho]**2 = power RC? Because the Zo cancels out anyways
(a ratio)?
?????????????????????????????????????????
Slick
I've been reading a lot concerning this subject on this NG. It appears
to me that a lot of words have been spilt over only an academic issue.
The reason is that the loss in coax the we use at HF, or maybe even at
MF, is so low as to be insignificant. The voltage/current phase angle
becomes significant on the lines we use only at low frequencies in the
audio range. If the discussion is only to provide further education on
the subject, fine, but some readers might get the impression that a
little line attenuation is a worrisome thing.
Walt, W2DU
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