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Old August 20th 03, 02:40 AM
Owen Duffy
 
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Dave Shrader wrote:
Total loss = 10*log((a^2-|rho|^2)/(a(1 - |rho|^2))

ARRL Antenna 18th edition, Chapter 24, Equation 15

Whe a = matched line loss = assumed 1


The reference calls quantity "a" the "matched line loss ratio", and a
value of 1 means no loss.

Does this mean that you are calculating the line loss in a lossless line?

rho = 0.8181 reflection coefficient for VSWR = 10

+ + +

OOOPPPSSS!!! Math error!

Reviewing my calculations I made a major math error!! Glad I kept the
work sheet.

In the numerator I used rho^2 not (1 - rho^2).

Now I am glad I retired from Engineering. :-)

Thanks again Roy!!

Conclusion, after I failed my ALGEBRA course, sheepish grin, the
additional loss is zero within the stated assumptions. Which just proves
I made 'Much ado about Nothing'.

Deacon Dave, W1MCE

I'll say three Hail Mary's and three Our Father's, assuming I can still
count to three!!

+ + +

Roy Lewallen wrote:

You've still lost me. ... Where did it come from? How was it calculated?

Roy Lewallen, W7EL




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