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Old June 14th 11, 07:58 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Reflection coefficient for total re-reflection

On Tue, 14 Jun 2011 11:26:41 -0700 (PDT), walt wrote:

Hi Walt,

The focus seems to have shifted away from the matching hardware
previously described to:
What I'm really concerned about is the reflection coefficient at the
output of the tank circuit of the RF power amp.


It includes a point argued by many, and which you make a condition of
success for your argument:
Being non-dissipative
it cannot absorb the reflected power, so it must re-reflect it.


Your argument now applied at two points, one not illustrated in your
references (the source):
Therefore, my position is that its reflection coefficient rho = 1.0,


The counter argument:
My critics say that a rho = 1.0 cannot be established when the virtual
short is caused by wave interference.

which they express NOT as a condition of the tank circuit, but of the
matching hardware.

However, if Best's Eq 8 is
valid,


You have acknowledge that experts in math whom you trust say it is
valid. This yields a paradox. By all the shifts in focus, it is
apparent that:
1. You are both right;
2. You are both wrong.
3. One of you is right, and one of you is wrong;
more likely given the drift of focus:
4. You are at cross purposes and arguing two different things.

Now that I've narrowed the problem down, what do you believe is the
answer?


You have not narrowed the problem down at all. It is composed of a
succession of premises that all have arguments for-and-against them.
This compounds the uncertainty. It also brings the hazard of any
single premise being rejected bringing down the entire goal you are
pursuing.

* * * * * * * * * * * * * * * * * * *

To put this bluntly, let's test the assertion repeated he
output of the tank circuit of the RF power amp.
Being non-dissipative
it cannot absorb the reflected power, so it must re-reflect it.


Odds are, you will lose support from at least half of the readership
for this statement alone - and it isn't even in your written work that
I've provided links for, and it certainly doesn't appear in Johnson.
It is not discussed by the experts in math either. It is a flyer, a
leap of faith whose validity is now emeshed with the outcome of
another problematic discussion.

Steve's opinion:
viz.
"A total re-reflection of power at the match
point is not necessary for the impedance
match to occur."

offers NOTHING to the matter of non-dissipation.

Odds are, Steve could easily lose support from at least half of the
readership for this statement alone. Unfortunately, that doesn't
leverage your position one iota.

There are too many irons in the fire.

73's
Richard Clark, KB7QHC