NanoVNA Sorts Unknown Ferrite Suppression Beads

[@SpinStar1956]

At 1:36 in your video, you say to perform the calibration procedure, and you show a cal-device connected directly to the NanoVNA port; and you make careful-mention of using a short piece of wire through the bead. However this is NOT the same test-plane as your elongated test-jig. There will be both substantial inductance in the jig's length and some capacitance in all the connectors. All calibration should be done right at the screw-terminals of your test-jig; and can be easily accomplished across the screw-terminals using a short-wire, 50-ohm non-inductive resistor and finally just the open screw-terminals.

[@reedreamer9518]

It is a bit cumbersome using 2 software programs to get an impedance sweep, so why not do the measurements right on the nanoVNA? I measured a type 61 core (Fair-Rite #2661540002), using a minimal wire loop length soldered directly to a 50 Ohm SMA connector and properly calibrated from 50 kHz to 900 MHz. Setting the trace format to Resistance (S11 |Z|) gives you the same data as Zplot (I did both methods as a check). I get a curve starting with Z=0 @50kHz, ~300 Ohms @144 MHz, a maximum value of 370 Ohms @260 MHz, 290 Ohms @440MHz, and 128 Ohms @900MHz. However, according to the Fair-Rite datasheet, Z values increase from ~0 Ohms @1MHz to a maximum Z value of ~460 Ohms @600 MHz, then falling off towards 1GHz. So why does the nanoVNA empirical measurement give me a completely different curve compared to the Fair-Rite datasheet?

[@geokuf9679]

Absolutely fantastic video. Very useful. Thank you for taking the time to do this. Waiting for pat 2 :-)

Thank you very much! Looking forward for the next video, and on how can the NanoVNA accurately identify the material mix type. Challenge: before Fair-Rite used a LCR meter and a DVM... Now, can you provide us a way to use the NanoVNA? All the best from the Amateur Radio community! Luís, CT2FZI

[@KD0CAC]

Getting to know VNA's - shouldn't the frequency be set BEFORE CAL ?

[@mike65535]

No BS video. Excellent.

[@jbammi]

Thanks for the helpful video. What i cannot understand is why Fair-Rite does not mark their Beads/Toroid etc., everyone has this problem. Surely this is not a un-surmountable technical challenge. Will appreciate an answer from Fair-Rite.

[@brucesparrow2236]

You are correct, its not insurmountable and we currently do some laser etching of part numbers for special applications. We are looking at various methods such as color coding or other markings that would identify the core. While it seems easy to do, the same size case is used for different ferrite mixes. If each snap-it had its own uniquely identified part number we would need a large increase in case inventory and core assembly space which right now isn't immediately available. Stay tuned, we will get there

[@jbammi]

@@brucesparrow2236 Has Fair-Rite made any progress to this end as you indicated previously.

[@reedreamer9518]

@@jbammi Based on the looks of their new stock, I'd say no (no progress). But this type of change would require some employee in the company to have dare and initiative, but since most corporate cultures are suppressive to any new initiative I'm sure the idea has been shot down and suppressed. Better get used to wasting hours of time figuring out WTF kind of core you've got.

[@glaros0]

Great video thanks. Which NanoVNA model is this exactly? From the video it appears to me to be the nanoVNA-H4 (?). Good piece of instrument, only drawback I see is the number of frequency points (100), which could miss some narrowband dips over a broad frequency sweep. But, I am still convinced that it's worth buying it, considering the features vs. price. 73.

[@brucesparrow2236]

Hi Kostas - yes, its the H4 version, 73, N2KTV

[@galileo_rs]

H4 with latest firmware has 401 points and that is in the standalone mode. When used with a computer the number of points is practically unlimited.

[@glaros0]

@@brucesparrow2236 many thanks for the confirmation. Looking forwards for your next video, 73

[@glaros0]

@@galileo_rs thanks for spotting this, apparently not many people pay sttention to this parameter, 73

[@stevec2196]

You should post a usable link to download the program since Github just gives you a lot of ridiculous nonsense but no installation files!

[@FairRiteProductsCorp]

I admit GitHUB is not user friendly. Use this link, find version 3.8 down the page, and you can download the version for your operating system, MAC, Windows, etc github.com/NanoVNA-Saver/nanovna-saver/releases

[@stevec2196]

@@FairRiteProductsCorp OK thanks. Can this method be used to also check large Ferrite cores like the ones used in Baluns?

[@paulkobetz554]

Another TU. With a box full of unmarked toroids it would be nice to ID them finally.. Moral ...always make them BEFORE placing into box! 73 de K2HZO

[@galileo_rs]

For the next video and when comparing with a professional VNA make sure NOT to use ideal standards, input the coefficients for the standards that you got with the device.

[@brucesparrow2236]

Will do, thanks for the advice

[@Pixelwaster]

zplots may be free, Excel is not.

[@user-lp3cf5yn5b]

And it's hell to find in 2024