On Thu, 28 Aug 2003 05:58:09 -0500, W5DXP  
wrote: 
 
Richard Clark wrote: 
 "...the generator impedance is 100+0j ohms, and the line is 5.35 
 wavelengths long." 
 
What does the generator impedance have to do with line losses? 
 
Hi Cecil, 
 
From Chapman (you following this George?) page 28: 
 
"It is reasonable to ask at this point how, for the circuit of 
Fig. 3-1(b), page 18, on which the above analysis is based, there 
can be voltage and current waves traveling in both directions on 
the transmission line when there is only a single signal source. 
The answer lies in the phenomenon of reflection, which is very 
familiar in the case of light waves, sound waves, and water waves. 
Whenever traveling waves of any of these kinds meet an obstacle, 
i.e. encounter a discontinuous change from the medium in which 
they have been traveling, they are partially or totally 
reflected." 
... 
"The reflected voltage and current waves will travel back along 
the line to the point z=0, and in general will be partially 
re-reflected there, depending on the boundary conditions 
established by the source impedance Zs.  The detailed analysis of 
the resulting infinite series of multiple reflections is given in 
Chapter 8." 
 
The Challenge that I have offered more than several here embody such 
topics and evidence the exact relations portrayed by Chapman (and 
others already cited, and more not).  The Challenge, of course, dashes 
many dearly held prejudices of the Transmitter "not" having a 
characteristic source Z of 50 Ohms.  Chapman also clearly reveals that 
this characteristic Z is of importance - only to those interested in 
accuracy. 
 
Those hopes having been dashed is much evidenced by the paucity of 
comment here; and displayed elsewhere where babble is most abundant in 
response to lesser dialog (for the sake of enlightening lurkers no 
less).  Clearly those correspondents hold to the adage to choose 
fights you can win.  I would add so do I!  The quality of battle is 
measured in the stature of the corpses littering the field.   :-) 
 
So, Cecil (George, Peter, et alii), do you have an answer?  Care to 
take a measure at the bench?  As Chapman offers, "just like optics." 
Shirley a man of your erudition can cope with the physical proof of 
your statements.  ;-) 
 
The only thing you and others stand to lose is not being able to 
replicate decades old work.  Two resistors and a hank of line is a 
monumental challenge. 
 
73's 
Richard Clark, KB7QHC 
		 
		
		
		
		
		
		
		
		
	
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