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QUOTE: ........ but should we ever be concerned that CMC might have fc different from the rest of the system? All my CMCs are home brewed and meticulously measured with professional instruments. My

Hi Miro I believe you asked the right question here. In my opinion, not having the correct characteristic impedance (Zc) for the CRC that matches the Coax/Antenna system slightly alters the impedance

12, 10, and 6 meters might be a bit of concern. But usually these are at or less than an electrical 0.1 wavelengths long. The characteristic impedance of all that I've built and measured (well over

Assuming that "wires" (transmission line) used to make CMC are much shorter then "lambda" across useful frequencies, how much impact do you expect from "mismatched" characteristic impedance of CMC?

When using the rectangular display, you can see that results may be compromised by the limited resolution of the magnitude/angle data, which is 0.001 in magnitude. You can see that the magnitude

Thanks, Alan. Using dot mode makes it easy. The upper Q = 1 intersection is between two data points. The lower intersection is close to one point, at which I've put the marker. A little calculation,

Here is a resonator s1p file that you can apply to the Q=1 contour. Capture the Q crossings at upper and lower (XL , XC) positions on the chart along with the zero real crossing. This provides

Using dots can have a fascinating decorrelation effect. This is group delay for a crystal filter. The response is 80 dB down outside the passband, as shown in the second image. Group delay gets noisy

I should have added this file listing to my previous post. The lin/log switch occurs in the middle. It's at 720 MHz, not 7.2 GHz. My ability to count zeros is restricted to "one, two, three, many."

I'm going to add an option to plot data points without a line connecting them. This is useful for assessing the data density, which is not always evident in a normal curve. The sample below reveals

Excellent.

No, but clicking the mouse will put a marker at the data point nearest the mouse cursor. Then you can use the mouse wheel to step up and down the curve to the desired point. I'll think about

Hi Dave Here My message about RG213 coax measurements posted here on Avril 5 2025: for My RG213 cable (25m length) loaded by a 50.3 Ohm resistor , I used the centered impedances circle methode on

Thank you. Are the data points from the s1p or s2p file highligted on the plot? A cursor that is positioned at or near an input file value is needed. For example, the crossing of a Q contour or SWR

Thanks, Alan. That's what I figured, but I have no experience with Smith charts so I wasn't sure. I've posted the latest here: https://k6sti.neocities.org/splot.htm Brian

No. Two different tools applied as needed, others may have different opinion.

@DiSlord Is it possible to add a function for constant SWR-circles on the Smith-chart of NanoVNA, for example SWR 2 and SWR 3, perhaps in red color? Maybe also in the NanoVNA-App-D as I think it was

Alan, currently I do not provide a way to display SWR circles and Q contours at the same time. Should I? Brian

Hi Dave This method of direct experimental measurement, without any computational artifice and without the risk of modeling errors or theoretical estimations, is simply my own used method, which I

Excellent, Very nicely done.