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Old October 4th 03, 03:26 AM
Walter Maxwell
 
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On Fri, 3 Oct 2003 22:57:54 +0000 (UTC), "Reg Edwards"
wrote:

Just a comment.

Whereas it is true the SWR remains relatively constant along a relatively
low loss line, it is NOT true that the reflection coefficint remains
constant. Its phase angle (1/2 of the information it contains) varies in
proportion the distance from the termination.


A little further comment.

The magnitude of rho is always the ratio of reflected to forward voltage at
whatever whatever point it is measured on any lossless or non-lossless line. On
lossless line the magnitude of rho is constant along the entire line, but
decreases logarithmically with distance from the load,depending on the
attenuation of the line.

However, the phase angle of rho equals the angular difference between the
forward and reflected waves. Because they are traveling in opposite directions
the rate of angular change is twice the change in electrcal distance along the
line. Thus the phase angle of rho changes at twice the change in electrical
distance along the line, varying between zero and 180 degrees for every 1/4wl.

Walt, W2DU