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A comment on Smith Chart.

Re:Smith Chart by madengr on Friday November 22, 2019 @08:53PM (#21611895)
No way is the Smith Chart outdated. I use it daily in simulation software and on the VNA. If a Smith Chart is not shown in a meeting, then that meeting is a waste of time.

I have a collection of various RF slide calculation tools. The prized one is rotary sliding Smith Chart.

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Re:Smith Chart by krapht on Saturday November 23, 2019 @05:02AM (#21613351)
This is so funny to me. At my workplace we preferred magnitude phase plots and tables. People had to be reminded how to interpret Smith charts
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Re:Smith Chart by madengr on Saturday November 23, 2019 @09:03AM (#21614145)
That makes sense for forward response, when you are optimizing for bandwidth or phase matching, or tuning for frequency response. Smith Chart is pointless for S21, though polar isn’t, though the VNA well let you do the former.

When I’m working on antennas, I’ll have both Smith Chart and log return loss plots stacked on top one another.

Say you want 15 dB return loss at some frequency, well there are two impedances points for that. One with the impedance locus outside Z0, and another with the locus encompassing Z0. The latter has broader bandwidth, but that intuition is lost without a Smith or polar plot.

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