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Old September 8th 06, 03:47 PM posted to rec.radio.amateur.antenna
Walter Maxwell Walter Maxwell is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 233
Default Source matching influence on line VSWR


The problem with doing experiments to "prove" a well-known principle is
that it's often very difficult to get good experimental results. So when
the results don't agree with the established theory, too many
experimenters become convinced that they've disproved the principle.
What they should be doing is figuring out what went wrong with the
experimental measurements.

In this case, I'm relieved that the experiment does agree with the
theory which has been established, used, and proved for more than a
century rather than with amateur folklore. If it hadn't, it would have
proved only that the experiment was faulty.

Roy Lewallen, W7EL


Owen, believe what Roy just said, because it's true. In fact it's the best
explanation of the concept that I've ever read.

Do you have Johnson's "Transmission Lines and Networks"? He was chairman of the
EE Dept at Princeton. On Page 100 he says, 'The steady-state ratio E+/E- is
defined as the reflection coefficient 'k'...The ratio is determined only by the
load and the line, not by the generator. It is completely unaffected by the
quantity 'kg', which is the coefficient seen by an individual backward-traveling
wave as it reaches the generator terminals. The latter affects the steady-state
solution only through its influence on the sending end voltage, i.e, through its
influence on the magnitude of the entire solution."

Hope his nips any new myth in the bud.

Walt, W2DU