Thread: Paralleling Transmission Lines
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Old April 22nd 10, 09:35 PM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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Default Paralleling Transmission Lines
Cecil Moore wrote in news:d6ea0bf4-7bb4-4089-9c88-
:

What happens when two paralleled transmission lines are of different
lengths? How does one analyze such a problem? For instance, what
impedance is seen at the source when a 30 foot run of 450 ohm ladder-
line is paralleled with a 20 foot run of the same line when the common
load is 100+j200 ohms? Will EZNEC handle such a problem? What if the
two different length paralleled transmission lines are not the same VF
and/or not the same Z0? Does superposition work for such a problem?

Here is an opportunity for you to do some leg work Cecil.

I have modelled in RFSIM99 a load of 100 ohms in series with 9.1µH at
3.5MHz with 30' of lossless 400 ohm line, vf=0.9, and 20' of lossless 450
ohm line, vf=0.8 as you describe. The input impedance is 767+j296.

Do you get the same result with a valid model in EZNEC?

Owen
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