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Old June 6th 05, 08:48 PM
Gene Fuller
 
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Cecil,

I do not expect that the reference you seek can be found.

There is no need to invoke interference or wave cancellation to explain
anything, and it is unlikely there is any mathematical formulation that
uses interference as one of the input variables.

It is totally unnecessary. Maxwell's equations contain everything needed
to accurately describe electromagnetic interactions, including wave
reflections, cancellations, and interference.

Any serious treatment of the subject of electromagnetic interactions
begins with the field equations, not with the resulting interference.
The sort of description found on the Melles-Griot web site and on their
CD-ROM is a handwaving, but comforting, description meant for general
understanding, not for detailed analysis.

73,
Gene
W4SZ

Cecil Moore wrote:
Gene Fuller wrote:

Cecil, You can't be serious!
This is basic stuff found in virtually any intermediate level E&M
textbook.



If you can provide me with a reference that says, wave cancellation can
cause reflection of the canceled waves, I will be eternally grateful.
I have been able to find references that imply such for light waves,
but I have not found one that comes right out and says it for either
light waves or RF waves.

I agree with you 100%. I had this "basic stuff" taught to me at Texas
A&M half a century ago. But Roy's "food for thought" stuff completely
ignores exactly that "basic stuff" concerning constructive/destructive
interference. Nowhere in his arguments is "interference" even mentioned.
I expect him to respond that interference is irrelevant. Dr. Best
went so far as to deny that interference is necessary for a Z0-match to
occur in a system with reflections. That was around May/June 2001 on
this very newsgroup for anyone who wants to Google it.

I have been fighting this battle for three years on this newsgroup.
Now you say it's "basic stuff". I've agreed for three years, but
where have you been all this time?

The treatment is generally the same; start with the field equations
describing the waves, add the material conditions and the boundary
conditions, plug and crank. The answers pop right out. No need to
invoke any magic incantations about interfering waves or wave
cancellation. The interference is the result of the analysis, not the
cause.



Some people have forgotten what they learned in college. Their net/
steady-state shortcuts have become reality and scrambled their brains.
You are obviously not one of the people at whom I aimed my remarks.
I am glad to see that not everyone has been seduced into thinking
that interference is irrelevant.

In the classical case, there is absolutely no difference in behavior
between "RF" and "optical". The material properties for every
situation can vary, but the physical principles do not.



I know that. You know that. We are on the same side. Now convince the
RF gurus of that. Roy calculated the net power at the source and
assumed from that figure that there was not enough energy available
to support the energy in reflected waves.

Sooo, rather than introducing a new concept, you are perhaps the last
person to finally understand the old one.



No, not the last one. What you say is exactly what is wrong with
Roy's arguments that reflected energy doesn't flow from the load
back toward the source. I am NOT introducing a new concept. I am
introducing a new (or forgotten) concept to some of the RF gurus
on this newsgroup. I am (re)introducing destructive/constructive
interference concepts to Roy, Dr. Best, and others.