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Good evening! I would very much appreciate recommendations on the best version of the NANOVNA that displays reactance values for the markers on the Smith chart, instead of inductance and capacitance.

Excellent Mike. So that is a Qul of 348. I spilt the difference between 6 and 8 ohms... lets say 7... From the appearance of your coil, that seems reasonable. The material you wound the unit on has a

OK I had a go at this with my NanoVNA and got the attached result, which if I follow your calculation correctly equates to Rq = 8.05 ohms. Coil64 estimates 5.9 ohms which, given the less than ideal

Return it and get a refund. Then go to R & L Electronics and purchase a genuine one. Problem solved!!! PS... This is the very best advise ANYBODY can give you!!!

Alan I found the article from your earlier link and will give it a go, thanks. In the meantime I repeated my measurement with NanoVNA-App calibrated for 6401points and got a slightly lower value of

I had the thought to get one some time back, and started looking on ebay. It's amazing how many of these units do NOT have any of the coils with them! I know of one guy who took on one of those and

Mike, the article is in this file

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