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Old March 7th 08, 09:39 PM posted to rec.radio.amateur.antenna
Keith Dysart[_2_] Keith Dysart[_2_] is offline
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First recorded activity by RadioBanter: May 2007
Posts: 492
Default The Rest of the Story

On Mar 7, 1:16*pm, Cecil Moore wrote:
Roger Sparks wrote:
Thanks for the additional explaination. I am wondering if I misunderstood Cecil's original premise.


Roger, if you thought it involved any instantaneous
values then, yes, you misunderstood my premise.


My understanding of your claim was that for the special case of
a 45 degree line supplied from a matched source, the energy
in the reflected wave is dissipated in the source resistor.

This sentence fragment from your document suggests this:
"reflected energy from the load is flowing through the source
resistor, RS, and is being dissipated there".

As "proof" of this, you computed average powers and showed that
the dissipation in the source resistor increased by the same
amount as the computed average power in the reflected wave.

But when an attempt it made to validate your claim using
instantaneous energy flows, the claim is proved false because
the dissipation in the source resistor does not occur at the
correct time to be absorbing the energy from the reflected
wave.

To prove your claim, I can see two paths:
- find some element in the circuit that stores the energy from
the reflected wave and releases it into the source resistor
at the correct time
- allow the violation of the principle of conservation of
energy

On the other hand, if you want to modify your claim to simply
be that the numerical value of the dissipation in the source
resistor has the same value as the pre-reflection dissipation
plus the numerical value of the energy in the reflected wave,
then the discrepancy is resolved. But then you can not claim
that the energy in the reflected wave is dissipated in the
source resistor.

...Keith