May 19th 11, 10:09 AM
posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Mar 2008
Posts: 329
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Transmitter Output Impedance
On 19 mayo, 11:05, Wimpie wrote:
On 19 mayo, 00:58, Cecil Moore wrote:
On May 18, 5:42*pm, John KD5YI wrote:
So, we are saying that the load at the line input can be viewed as a
lumped circuit. So now we have a transmitter loaded with a lumped
circuit for further analysis.
It doesn't quite work that well. I gave an earlier example where Wim
got the the s11 parameter wrong by an infinite percentage. The s-
parameter equations for a lumped circuit vs an impedance discontinuity
are nothing alike.
Hello Cecil,
Would you please remind me to the example where I was completely wrong
with S11?
Even the IEEE definitions for the two different
types of impedances are different. The interference conditions at the
impedance discontinuity can be proven to be different than for the
lumped circuit replacement.
That's all. It's simple.
Quoting Einstein again: "Everything should be made as simple as
possible, but no simpler." :-)
When you switch to the lumped-circuit model, you are agreeing to
faster than light signal speeds, NO superposition of signals, zero
interference, zero phase shifts through coils, identical current
everywhere, etc. How the heck can you assert and prove there is zero
interference inside a source when reflected energy is flowing through
it?
Did you ever DESIGNED some serious electronic hardware? I am not
pointing to using a recipe book or troubleshooting/repair.
--
73, Cecil, w5dxp.com
Regarding your helical; I don't have Eznec. Maybe you can use some
screenshots from it, put some comment to it and put that on website,
so we can view it.
Wim
PA3DJS
www.tetech.nl
remove ED from designed....
Wim
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