NanoVNA V2 / Forum

Note: this page is a mirror of https://groups.io/g/NanoVNAV2.
Click here to join and see most recent posts.

how to measure coil/filter inductance with NanoVNA v2 plus4


sq8guo 2021/09/22 07:45

hi All,
my very first post here, as I couldnt locate on the web how I can measure uH of a coil. I have here e.g. some Toko-style 5.1mm coil which I wound for say 40m band. I have calibrated Nano so that I could measure my coil (which I will use in BPF later on with another one like this), but need to find out what is its incuctivity.

I measure it so that on Port 1 I have it hooked up i.e. hot wire to one coil' end, and another to shunt. When looking at YT videos other guys had on the SMITH chart the resistance value in Ohms and inductance in uH. I have instead of uH, capacitance value, and I do not see in Display/Format any option for Inductance.
The formats which are in there are:
POLAR
LINEAR
REAL
IMAG
RESISTANCE
REACTANCE
Q FACTOR

Am i having outdated firmware? or NanoVNA v2 plus4 doesnt allow us to measure inducivity, stray capacitance, stray resistance and all these sorts of tiny bits which might influence our home made circuits?

Any info, links would be much appreciated.
all the best
Waldi,sq8guo

owo 2021/09/22 21:28

Hi Waldi,

The Inductance/Capacitance automatically displays, for a capacitive load it will show for example 50 ohms + 1 pF and for an inductive load it will show for instance 50 ohms + 0.1 uH.

If you toggle the different traces back and forth you may achieve the desired display. Reactance is the term you want here, but try setting all the traces to different values.

Also, you may need to terminate your inductors with 50 ohms to ground for an appropriate measurement.

73

WD0FYF Gerald 2021/09/25 09:53

Owo,
I thought I understood, then I wasn't so sure. Does the 50 ohm load go in parallel with the reactance I want to measure or does it go in series to ground?

Thanks,
Gerald WD0FYF

Guido de winter 2021/09/26 09:35

Groeten Guido

owo 2021/09/26 08:28

https://forums.qrz.com/index.php?threads/using-vna-to-measure-coil-inductance.681215/

Roger Need 2021/09/26 09:42

We had a long discussion on this topic in the NanoVNA group.  You should find lots of good info there.

https://groups.io/g/nanovna-users/topic/80744049#20809

Roger Need

To reply to this topic, join https://groups.io/g/NanoVNAV2

View this thread on groups.io