Tom Donaly wrote: 
"You and Richard Harrison are beginning to sound lke Bishop Berkeley." 
 
We are in good company. Terman says on page 84 of his 1955 opus: 
"In these equations Zo = sq rt Z/Y is termed the "characteristic 
impedance" of the line. In the case of radio-frequency lines, Zo can 
nearly always be assumed to be a pure resistance, as discussed on page 
88." 
 
When Terman says SWR = Emax / Emin, it makes no difference whether you 
use instantaneous values or rms values, so long as you are consistent, 
the ratio is the same. 
 
Some complained that nobody provided a trustworthy VSWR related to 
power. Bird Electronic Corporation does: 
 
VSWR = 1+sq rt (reflected pwr/forward pwr) over 1-sq rt (reflected 
pwr/forward pwr). 
 
Millions of conversions have proved this VSWR from measured powers 
relation. 
 
Best regards, Richard Harrison, KB5WZI 
 
		 
		
		
		
		
		
		
		
		
	
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