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Old January 28th 08, 04:30 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 Derivation of Reflection Coefficient vs SWR

Keith Dysart wrote:
Unfortunately, this is quite wrong. And I continue to
be surprised that you argue that there is a reflection
where there is not an impedance discontinuity.


Since an absence of reflections violates the conservation
of energy principle, there is something wrong with your
assertion and your earlier example was proved to contain
a contradiction.

Psource = Pfor - Pref = Pload

Pfor = Psource + Pref = Pload + Pref

Those equations are true only if reflected energy
does not flow back into the source. I suspect that,
contrary to your assertions, the actual real-world
source presents an infinite impedance to reflected
waves.

When you decide that you do not want to argue that
reflections occur where there is no impedance
discontinuity, ...


You simply fail to recognize the impedance
discontinuity.

Please perform the following experiment to prove
there is no impedance discontinuity and no distortion
and get back to us.

zero ohm
TV RCVR--+--TV source--+--Z0 stub----------open
|
Z0 source impedance resistor
|
GND

The source output goes into the stub. Reflections
occur at the open end of the stub and flow back
through the zero impedance source to be dissipated
in the Z0 source resistor and displayed without
distortion on the TV RCVR. If what you say is true,
it should be duck soup for you to prove.
--
73, Cecil http://www.w5dxp.com