Recently I've been exploring what the NanoVNA can do. It really is an impressive piece of test equipment for such a small sum. There has been lots of discussion about measuring passives at HF but I was troubled by the lack of evidence that some commentators had actually done what they advocated. Just like fake Chinese transistors, too many online experts write on the basis of what they have read, not what they have done.
And there was very little online information I could find about using the NanoVNA to measure very small values of passive components. What information I could find was at times inconsistent. So I set out to discover for myself what worked. Over the next few weeks I'll post what I found.
But first the starting point has to be the text fixture. I had a PCB house fabricate a few boards so I could experiment. A variety of single and doubled sided layouts were contemplated, some would use a 50ohm chip resistor in series with the passive being tested, some would simply place the passive component across the SMA.
My biggest challenge was presenting the test results. Taking a picture of the screen was impossible given the screen reflections. "nanoVNA partner" is a small download and worked well on both XP and Windows 10. I recommend it.
As far as using the NanoVNA, at least one published paper would appear to advocate a different approach to what I found. Could it be the NanoVNA was better than the equipment used in that published paper?
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