"David Robbins" wrote in message ...
sorry, no scanner here.
how do you get rho1? please give me the Zo and Zl to try out, i have been
playing for a while with the basic equations and haven't found a case where
either formulat gives rho1.
and of course if |rho|=1 then swr can never be negative.
I think Reg put it best:
"Dear Dr Slick, it's very easy.
Take a real, long telephone line with Zo = 300 - j250 ohms at 1000 Hz.
Load it with a real resistor of 10 ohms in series with a real
inductance of
40 millihenrys.
The inductance has a reactance of 250 ohms at 1000 Hz.
If you agree with the following formula,
Magnitude of Reflection Coefficient of the load, ZL, relative to line
impedance
= ( ZL - Zo ) / ( ZL + Zo ) = 1.865 which exceeds unity,
and has an angle of -59.9 degrees.
The resulting standing waves may also be calculated.
Are you happy now ?"
---
Reg, G4FGQ
If it were not for Reg pointing out this example, i wouldn't have
researched and corrected my original, "purely real" Zo post with the
more general conjugate Zo formula.
And i researched it because i knew that you cannot have a R.C.
greater than one for a passive network (you can only have a R.C.
greater than one for an active network, which would be a "return gain"
instead of a "return loss"), so i knew that when Zo is complex, my
original post must have been wrong.
Intelligent people can be close-minded, that is for certainly, in
which case, their intelligence is blunted.
Slick
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