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If difficulty in finding the paper from EDN and the figures, here is a pdf abbreviated and a test case circuit screen capture. If you are careful in fixture construction depending on operating

I occasionally see them for sale at hamfests. I have gotten a few that way, but I shouldn't have - I haven't used any yet. Not even the big, (relatively) heavy old U.S. military one. If you look for

I am using nanoVNA-H The product was purchased on Ali Express, and I thought it was genuine, but it was fake. First of all, I am a Windows 10-64bit user. What did you do to solve the problem 1.

Thanks Alan I'll have a look at that. -- Mike

Mike 15 ohms is not too far from what a long inductor made with small gauge wire could have. Q of about 143. Pete

Mike, Scratch that idea about the scales because it doesn't work the same at 4 MHz where the Z should be about +j503 ohms.

Mike Is the scale of your reactance graph supposed to be in kohms and not just ohms? I think so because at 3 MHz the impedance of the series L-C would be about -j911 ohms. Correct? Pete

Hi Mike, Please see message # 23812. This documents one approach. Alan

What happens when you try to calibrate it? "Can't get it calibrated" isn't very specific. Does the unit fail to respond correctly at some point in the calibration procedure?

Hi Pete, it's an air cored coil with an inductance of around 108uH. I made the measurement with an 18pF COG capacitor in series so the plot is showing the resistance around the resonant frequency of

For HF and higher frequencies, L >> R and C >> G are generally good assumptions. We can then simplify the general expressions for complex characteristic impedance and complex propagation constant to:

Hi MIke What component type are you using for the test? Trying to understand why the R is changing myself. I would think the resistance of a fixed series resistor would remain fairly constant if it

Doug, I have seen this demo and observed that the calibration procedure was i.m.o. not properly done. At marker 3:48 of the video you see that after the CAL button in the menu was pressed next the

OK if I may answer my own question, I repeated the measurement using the S21 method and got a sensible answer. -- Mike

Sorry, heres the graph with numbers! -- Mike

I've been following this article on how to accurately measure the Q of a coil: https://pa3a.nl/wp-content/uploads/2022/01/Measurements-With-The-NanoVNA-Part-7-Measuring-the-Q-of-a-coil.pdf I measured

Ok. I understand. If you cant remove coil from its surrounding circuit, a GDO is usefull. "(Why? Because oceans on Titan are likely liquid methane, ethane, etc)," interesting. Good luck with that

I also have a nanoVNA-F with which I am very satisfied: use f < 300 MHz). Thanks to this forum I was able to update the Firmware. It is not essential but we can thus recover the .sp1 and .sp2 files

Michael. Here is a very good demo re the NanoVNA. https://www.youtube.com/watch?v=1WkhsN9vZzM Doug -- This email has been checked for viruses by Avast antivirus software. www.avast.com

I use NanoVNA-Saver (which is in Python, and runs on any platform). Others like NanoVNA-App, which is Windows only. Those two seem to be popular. If you're looking for something minimalist, there's