I read the analysis earlier, and didn't and don't see how it constitutes 
the proof I proposed. 
 
Permit me to repeat the entirety of what I said, and not just the last 
sentence. I said: 
 
 I'll restate something I mentioned before (first incorrectly, then 
 corrected). Connecting a load to a transmission line which is the 
 complex conjugate of the transmission line Z0 does *not* guarantee 
 maximum power delivery from the source, or to the load. The load 
 impedance which provides maximum load power is the complex conjugate of 
 the impedance looking back from the load toward the source. That 
 impedance is the source impedance transformed through the transmission 
 line between source and load, and it's not generally the same as the 
 line's Z0, or its complex conjugate. When this condition of maximum load 
 power is met, there will almost certainly be voltage and current wave 
 reflections on the line -- there would be none only if the optimum load 
 impedance coincidentally happened to be equal to the line Z0. So the 
 argument that there can be no reflection of the voltage wave under the 
 condition of maximum power transfer is wrong. 
 
 You didn't show differently in your analysis, and no one has stepped 
 forward with a contrary proof, derivation from known principles, or 
 numerical example that shows otherwise. 
 
 
Now let's see if this constitutes such a proof. 
 
Peter O. Brackett wrote: 
 Roy: 
 
 [snip] 
 
You didn't show differently in your analysis, and no one has stepped 
forward with a contrary proof, derivation from known principles, or 
numerical example that shows otherwise. 
 
Roy Lewallen, W7EL 
 
 [snip] 
 
 Yes I did.  I guess that you missed that post. 
 
 I'll paste a little bit of that posting here below so that you can see it 
 again. 
 
 [begin paste] 
 We are discussing *very* fine points here, but... 
 
 [snip] 
 ratio of the reflected to incident voltage as rho = b/a would yeild the 
 usual formula: 
 
 rho = b/a = (Z - R)i/(Z + R)i = (Z - R)/(Z+ R). 
 
Here I'll assume that you've defined a and b as equalling the forward 
and reverse voltages in a transmission line, which is a different 
definition than in your other posting. With that definition of a and b, 
and if R is the transmission line characteristic impedance, then the 
equation is valid for a transmission line, and ok so far. Otherwise, 
you're talking about something other than a transmission line, so the 
"proof" doesn't apply at all. 
 
 In which no conjugates appear! 
 
 Now if we take the internal/reference impedance R to be complex as R = r + 
 jx then for a "conjugate match" the unknown Z would be the conjugate of the 
 internal/reference impedance and so that would be: 
 
 Z = r - jx 
 
So the load impedance is the complex conjugate of the transmission line 
characteristic impedance. Ok. 
 
 
 Thus the total driving point impedance faced by the incident voltage a would 
 be 2r: 
 
 R + Z = r + jx + r - jx = 2r 
 
Here you've lost me. a is the forward voltage in the transmission line. 
What can be the meaning of its facing a driving point impedance? The 
forward wave sees only the characteristic impedance of the line; at all 
points the ratio of forward voltage to forward current is simply the Z0 
of the line. So I don't believe that it sees 2r anywhere. 
 
This is where I'm stuck. If you can show where along the line the 
forward voltage wave "faces" 2r, that is, Vf/If = 2r, I can continue. 
 
. . . 
 
Roy Lewallen, W7EL 
 
		 
		
		
		
		
		
		
		
		
	
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