Which NanoVNA?

[clansd99]

Hi all,

To preface this - I've already done a lot of digging into the different "types" of NanoVNA out there (original, V2, Lite, etc.), but still unsure what the best options are.

I am currently learning RF electronics in school and would like to pick up a VNA to experiment with at home to go along with my coursework.

The LiteVNA 64 seems to be just what I want: high frequencies at a low cost, but I can't find much info on it and want to know more before pulling the trigger.
Is it compatible with other NanoVNA software? Who designs/develops it? Where can I buy one knowing that I won't get a knock-off?
Is it really better than the original and V2?

Thanks for helping a newbie out,
-Chris

[Bud]

Why do you want high frequencies? To learn S-Parameters concept and how different types of RF circuits behave a 50 MHz VNA is all you need. This also will MUCH simplify requirements to calibration standards and cabling.

[clansd99]

I'm interested in microwave engineering and would like to go down that path once I get the basics down on RF. Already have some projects in mind and figure it's better to spend on a higher frequency VNA now than a second one down the line.

[Bud]

OK. But just remember- there is nothing theory-wise different between an RF VNA vs microwave VNA. They both measure the same type of parameters for a DUT ( device under test). The difference is in mechanical and electrical toletances those devices have. With a microwave VNA you spend more money on quality of physical construction and quality and characterisation  of the reference (calibration) standards and quality of (usually coaxial) cabling that you will need to perform repeatable measurements. If you want price reference, a microwave phase stable cable jumper will cost a few hundred dollars. You heard that right, several hundred dollars just for one coax cable.

[clansd99]

OK. But just remember- there is nothing theory-wise different between an RF VNA vs microwave VNA. They both measure the same type of parameters for a DUT ( device under test). The difference is in mechanical and electrical toletances those devices have. With a microwave VNA you spend more money on quality of physical construction and quality and characterisation  of the reference (calibration) standards and quality of (usually coaxial) cabling that you will need to perform repeatable measurements. If you want price reference, a microwave phase stable cable jumper will cost a few hundred dollars. You heard that right, several hundred dollars just for one coax cable.

Hadn't thought about it that way. The YouTube videos make it look so easy but I don't have that much cash to spend. Will just go ahead and order the NanoVNA-H4 on Amazon and be done with it 
Hopefully I don't get a dud!

[joeqsmith]

Hi all,

To preface this - I've already done a lot of digging into the different "types" of NanoVNA out there (original, V2, Lite, etc.), but still unsure what the best options are.

I am currently learning RF electronics in school and would like to pick up a VNA to experiment with at home to go along with my coursework.

The LiteVNA 64 seems to be just what I want: high frequencies at a low cost, but I can't find much info on it and want to know more before pulling the trigger.
...

Thanks for helping a newbie out,
-Chris

Hello Chris. 

Is it compatible with other NanoVNA software?

There is certainly software available for it.   Much is open sourced. 

Who designs/develops it?

There is a groups.io specifically for the LiteVNA.  Consider joining that.   

Where can I buy one knowing that I won't get a knock-off?

I'm not sure from Canada but we bought ours from:
https://store2.rlham.com/shop/catalog/product_info.php?products_id=75669

Is it really better than the original and V2?

From your post above, I assume better = higher frequency and no other considerations play into it.  In this case, yes the LiteVNA is much "better". 

[MadTux]

Basic NanoVNA-F or H is good enough for learning, NanoVNA-F V2 if you want nice mechanical design, a bit more frequency range and better display.

Apart from that, NanoVNAs are build for low cost, low part count and tiny size, people at HP and Rohde-Schwarz did it better, 40 years ago.
Go for like an old HP-8753 if you want lab grade instrument, that doesn't do things like using square waves as test signal, that messes up most active circuits.

If they had increased budget by maybe $50-$100, the could have used something like a local oscillator/mixer design with a couple of ADF4350s in their pure spectrum range between 2.2-4.4GHz and a few switched filters to get a nice sinewave test signal istead of the nasty square waves from SI5351 and divided down ADF4350.

User interface/touch screen is implemented quite nicely, though.

[Smokey]

Say I wanted an instrument that would be used to set the matching components for a 2.4GHz Bluetooth chip antenna on a PCB. 

Is the LiteVNA64 or the "NanoVNA V2 Plus4" a better match?  Any big reasons to get one over the other?

[joeqsmith]

They are both low end devices and there has been a fair amount of data published from them.  Maybe you have a more specific question?

Off the cuff, the V2Plus4 is now over $250 and OUT OF STOCK
https://www.tindie.com/products/hcxqsgroup/4-nanovna-v2-plus4/

The LiteVNA64 is $130 and in stock
https://store2.rlham.com/shop/catalog/product_info.php?manufacturers_id=142&products_id=75669&osCsid=v97fjcvk96mordl770825mg2v0

That may be one reason to get the LiteVNA

[rsjsouza]

For $69 (or $78 with the cal kit), the nanoVNA H4 is hard to beat
https://www.aliexpress.com/store/1101394653

Locally to the US it is a bit higher but not terribly overkill
https://www.amazon.com/s?k=NanoVNA&me=A3KC9Z86M9XWS3

Since you might be young, you can get by with the smaller screen version as your eyes are not aging like us *ahem* "seasoned" enginners.

These stores were recommended by the NanoVNA project page at:
https://nanovna.com/

[nctnico]

For $69 (or $78 with the cal kit), the nanoVNA H4 is hard to beat
https://www.aliexpress.com/store/1101394653

AFAIK the H4 is not the best one out there. I used to have one but got rid of it.

[rsjsouza]

For $69 (or $78 with the cal kit), the nanoVNA H4 is hard to beat
https://www.aliexpress.com/store/1101394653

AFAIK the H4 is not the best one out there. I used to have one but got rid of it.

Interesting. Any practical annoyance worth mentioning? Its specs seem quite alright for basic testing in HF/VHF/UHF. I am sort of looking around (perhaps to make a decision later this year) and such information might weight in my decision.

[joeqsmith]

Clansd99 was asking about microwaves and later mentions that the LiteVNA64 seemed to possibly fit their needs.  Smokey was asking about 2.4GHz.   As far as I know, the H4 was similar to the original NanoVNA in that above 300MHz, it uses harmonics which really limits its use.   I have an H4 that is basically new in the box.  I was never able to find stable firmware for it and eventually put if back in the box where it remains.  That may have changed by now. 

Anymore, I use the LiteVNA and the original NanoVNA.  The original NanoVNA will out perform the LiteVNA at lower frequencies.  For example, making PDN measurements or measuring narrow band filters (crystal).   Having the two covers the bases.   

Because the original NanoVNA and H4 use a different protocol and getting stable firmware was so problematic, I no longer update my software to support them.   I have been very pleased with Dislord's firmware for the LiteVNA.

[rsjsouza]

joeqsmith, thanks a bunch for the insights about the NanoVNA. Apart from harmonics and if there are no other problems with it such as horrible bugs in SW, I think the NanoVNA is suitable for the HF/VHF/UHF ranges.

[joeqsmith]

I think that will depend on your definition of "suitable".  UHF covers 3GHz which unless they have further increased the range of the original NanoVNA and H4, you are missing half the band as the highest I have seen them allow was 1.5G.   Noise floor for my H4 up 300MHz is around 85dB.  My original NanoVNA is about 10dB higher.   I was pretty impressed when I first saw this and it was a major letdown to see the higher end V2Plus4 not performing at least as well.  I was expecting it to be improved.   Once you move beyond that 300MHz, shit hits the fan.   '

I have posted data showing how some of the low cost VNAs compare.  Some of this data was provided by various owners.  You can see both the H4 and original NanoVNA.   

https://www.eevblog.com/forum/testgear/warning-about-nanovna-clones-and-comparison-with-siglent-vna/msg4626466/#msg4626466

The H4 may be good enough for you personally but I tell people that if you want to experiment beyond 300MHz, get something else.   With the high price of the V2Plus4, lack of firmware support and lower frequency range,  I recommend the LiteVNA.     

Two problems with harmonics is the drive signal is very low and your circuit is still seeing the fundamental, with it's level.  Of course, you can try to work around that but better add that into the cost.     

I can't speak for the software side of things.  Maybe you are calling the VNA's internal firmware software?   I assume most people are using the open source software.   The software that was supplied  by the manufactures wasn't usable, which is why I started to write my own.

[rsjsouza]

6466/#msg4626466[/url]

The H4 may be good enough for you personally but I tell people that if you want to experiment beyond 300MHz, get something else.

I am an idiot. I was thinking of 300MHz when I mentioned UHF. Indeed the noise floor becomes quite unsuitable above that.

BTW, thanks for sharing the URL to the other discussion. I will look beyond the H4.

[joeqsmith]

The LiteVNA supports using harmonics as well which is the cause of the jump in the noise level at 6.3GHz in that plot.   You can see its on par with the H4 at 9GHz. 

Dislord (person supporting firmware for the LiteVNA) has provided a version of firmware allowing the LiteVNA to work up to 18GHz.  Of course the results are poor as we would expect.  I have shown it directly measuring a home made waveguide configured as a  10GHz bandpass filter.  The fact it shows anything close is very impressive considering its $120 and it fits in your shirt pocket.   Who would have guessed.   

I am experimenting above 10GHz by converting the lower frequency range where the LiteVNA has decent performance.  Much like how any radio works.  Results have been fair.  Link shows measuring S21 with the Lite stepping from 0 to -50dB at 11GHz.   

*** Better link showing both the filter and step attenuation
https://www.eevblog.com/forum/rf-microwave/nanovna-custom-software/msg4651535/#msg4651535

[xrunner]

The H4 may be good enough for you personally but I tell people that if you want to experiment beyond 300MHz, get something else.   With the high price of the V2Plus4, lack of firmware support and lower frequency range,  I recommend the LiteVNA.   

I have two nanoVNAs but I also have an H4 that a local ham wanted to trade me for my comet antenna analyzer. He didn't really understand the VNA so it worked out for him. I hadn't used it in a while but I was interested in how the ice storm we had affected my dipoles. All of the center frequencies were shifted lower which is understandable since the ice coating effectively made the wires "longer" since the ice coating ran all the way down the support ropes at the ends. About 500 kHz lower on 40 m.

Anyway, I just updated the firmware to v.1.2.08 and it seems to work OK for my needs. But I'm not opposed to upgrading to stay current. That is as long as I remember not to xmit into port 2 with an HT. 

[joeqsmith]

That poor guy.  We all make mistakes but that was a doosy. 

I pulled the H4 from the plastic wrapper and I'll be dammed if it didn't still have a charge and powered right up.  Looks like 1.0.38 was the last firmware I loaded.   Looks like they are up to 1.2.14.  I went ahead and loaded it in and fired up my old software.  It seems to connect just fine.   For some reason, they now allow 1.6kHz to 2GHz.  Fairly large error at 116MHz (see Smith chart).   Looking at the last time I had tried to run a regression test on it, the H4 failed the standard deviation test but at a different frequency range.   I would need to go back and read Dislords posts to see if there was a work around.   Guessing the ham antenna analyzer group wouldn't be too concerned as they don't use this frequency. 

[joeqsmith]

I let it run for a while.  You can see that error is always present but isn't constant.  Some sort of band switch point.  Zooming out to show the full 2GHz range, I don't see any other large errors like this. 

[rsjsouza]

joeqsmith, xrunner, thanks for sharing your thoughts and data.
Weird the 166MHz disturbance - a half harmonic spur of some sort coming from the PA?

To the OP: sorry for somewhat hijacking this thread, but hopefully this discussion also helps you with your decision.

[joeqsmith]

Looks like they sorted out the 300MHz spike I was seeing the last time I ran a regression test on the H4 but this 116MHz seems to be a new one.  Nothing was attached to the VNA.  It was not calibrated.  I suspect if I roll back the firmware it will clean back up.   Maybe the hardware is so poor they can't find settings that work in all conditions. 

https://groups.io/g/nanovna-users/topic/problem_300_mhz_spikes_on_h4/85266697?p=

Looks like I did attempt to upgrade it at one point but ran into other problems.
https://www.eevblog.com/forum/rf-microwave/nanovna-custom-software/msg4124581/?topicseen#msg4124581

This was basically my point about the H4's firmware being unstable.  As bad as it is, it's not the cluster fuck I ran into with the original NanoVNA.  I am still running Radiolisteners hacked up firmware on that.   The V2Plus4 worked out of the box but I didn't find firmware for the V2Plus until about a year later that wouldn't lock up and require a power cycle to reset.   The LiteVNA has been by far the most stable and bug free IMO.   But again, I really only use a very small subset of the firmware.   I just need the VNAs to send me the raw data and allow access to all of the peripherals.   There may be a lot of problems that I am not aware of simply because I don't use these features.     

       

[xrunner]

That poor guy.  We all make mistakes but that was a doosy. 

I pulled the H4 from the plastic wrapper and I'll be dammed if it didn't still have a charge and powered right up.  Looks like 1.0.38 was the last firmware I loaded.   Looks like they are up to 1.2.14.  I went ahead and loaded it in and fired up my old software.  It seems to connect just fine.   For some reason, they now allow 1.6kHz to 2GHz.  Fairly large error at 116MHz (see Smith chart).   Looking at the last time I had tried to run a regression test on it, the H4 failed the standard deviation test but at a different frequency range.   I would need to go back and read Dislords posts to see if there was a work around.   Guessing the ham antenna analyzer group wouldn't be too concerned as they don't use this frequency.

Hey Joe,

I was interested in this little "tick" but I can't get mine to display one. Wasn't sure I had it set up right the first time  but here is mine with no cal and no load (open). Probably still doing something wrong.

What do you think?

[joeqsmith]

Anyway, I just updated the firmware to v.1.2.08 and it seems to work OK for my needs.

Looks like they are up to 1.2.14.  I went ahead and loaded it in and fired up my old software. 

I suspect if I roll back the firmware it will clean back up. 

[rsjsouza]

That is as long as I remember not to xmit into port 2 with an HT. 

Wow, I missed that!