Questions tagged [smith-chart]

For questions related to Smith charts

For more information about Smith charts, see here: https://en.wikipedia.org/wiki/Smith_chart

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Beyond Maximum Stable Gain of a transistor

I was plotting constant-gain circles on the Smith chart the other day for a potentially unstable RF transistor. I recently read on-line that for a potentially unstable transistor the maximum gain that can achieved is the MSG or maximum stable gain.…
Thomas L
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Impedance matching using Smith Chart and relationship to reflection

I've been reading the impedance matching chapter of Bowick's excellent RF Circuit Design book and I have a question. For those who haven't read this book (or have but can't remember!), the chapter discusses L and 3 element matching networks (very…
Buck8pe
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How to determine if filter is well matched?

Hello i'm in process of creating band pass filters for my ham radio. I calculated the filter for 80m band basing on this website: And recreated it in reality: Then I started measuring it with nanoVNA, and tuning the trimmers to get best frequency…
fifi_22
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Obtaining input/out impedance from S-parameters for a L network

This L network intend to transform Z1 to 50ohms. The design was made using a smith chart: The s-parameters plotted (S11 red - S22 green) in the smith chart is done sweeping the frequency from 200MHz to 5GHz for this L network. If the reflection…
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CC1125 reference design matching network using Smith chart

I am trying to confirm on a Smith chart the matching network for 169MHz frequency using an external PA and and 437Mhz with an external LNA. I am not able to end at the origin of the Smith chart using the reference design provided. The transmitting…
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Smith Chart - constant resistance circle and infinite resistance at right

The Smith Chart has a single horizontal line with normalized pure resistance which run from 0 on the left to infinity on the right. Following the circle which starts at the normalized pure resistance of 1.0 has a constant normalized resistance of…
user34299
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Reflection Coefficient to Impedance transformation on the Smith Chart

A certain RF transistor has a source - reflection coefficient with a magnitude of .105 and a phase angle of 160°. When plotted on the Smith Chart, the normalized impedance is .825 +j .06 Ω. What is the actual or unnormalized impedance? What does it…
Thomas L
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