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Post Production Note: I received an email from one of the developers of the "V2" platform, and he informed me that while they intentionally open-sourced the design in order to give users more choice, there have been at least one clone maker that has manipulated the market in various ways (false rankings, and selling at cost) which does a discredit to the original developers. This is the case with the SAA-2N featured in this video. The official website for the V2, from the original developers, is nanorfe.com/nanovna-v2.html. Please consider this when making your choice about what V2 hardware to buy.

I ordered a nanoVNA to play with. It is good to understand the limitations as well as how they can be used. This comparison dramatically illustrates the clarity a better VNA provides, though, for casual use, cannot be justified in price. It would be interesting to see how this Tek VNA compares to some entry Rigol and Siglent units. Those are closer to my price range as a hobbyists.

I learned a bunch from this video. Even my NanoVNA can tell that the chinesium duplexer I bought only gave -46dB rejection with insertion loss of 4dB from the factory. If I can turn the screws and improve those characteristics a bit, I'll be a happy HAM!

Makes me happy I just bought the same nano vna with the N connections! Thanks for the video man!

Sir Your videos are alsom alsom alsom...... You tell events of rf electronics is perfect than many professors. I respect your works sir. Thanks a lot.

The nanovna is awesome for making filters, i was able to make a filter that worked perfectly and measure it. Great tool.

Nice to hear you after a long time.

Great video, thanks for easy to understand explanation!

For the price the Nanos are a great little tool, And getting better all the time , Who knows what they will be like performance wise in the next year or two as improvements are made in both hardware and firmware .... Again though Alan another great video.

Superb video and use-case for amateur ops!

Just a quick comment regarding NanoVNAs. As a radio broadcast Engineer I needed to retune an an antenna for an LPFM and the NanoVNA worked spot-on! I was able to get the antenna resonant on the station's frequency. A very handy device to have in the field. Thank you for all your videos and keep them coming.

Timely and perfect in my situation. Thanks a lot 👍

Great video on the Nano. I didn't know there was an SAA-2 until now. I'll have to look into it further.

You have been doing very nice videos, giving vast knowledge. I liked them very much but since all those stuff look very expensive, seemed hard to follow. Think of doing a series which ordinary hobbyists like us can follow will be a great idea. Your standard of knowledge in radio armature looks pretty amazing.

Great! Have just decided to buy an SAA-2N so at least I'll have a VNA toy now. (but still looking for a professional one though)

Hello friend, thanks for your video. Jorge from Medellín Colombia

Nice, thanks for sharing where website did you buy the SAAN 2N from? Thank You

Thanks for the heads up on the original source of these tools. I shall wait and save the extra bit for the latest V2 Plus4 in metal case..from the developers. Thank you.

Another great video, Alan An interesting follow up could be an exploration of low cost testing alternatives that could be successful at tuning a duplexer. Would an RTL-SDR dongle and a noise source be good enough? Better or Worse than a Nano VNA? I'm certain you can think of other old school and low cost methods of performing such a test. Keep up the great work.

Thanks for this :)

Wow, glad you are back. You make wonderful videos that instruct and entertain. Thank you. 73 KG5OBD

hi, you showed only one shoulder-LOW, in this shoulder everything is good, and what happens in the other shoulder-HIGH?

I’m chucking my “cheap” Rigol DSA815tg now... $1800 vs $60? 😷😆🤣 Seriously.. thanks for another great video. NORTH Jersey Rocks!

Great Video; cool example of where dynamic range really comes into play. 2 questions (1) Is 1kHz measurement BW the minimum size for the nanoVNA-H firmware you were using or is it possible to squeeze out a bit more dynamic range by going smaller; if not, is this a hardware limitation? (2) is the measurement BW adjustable in the SAAV2 firmware you were using?

With a Nanovna-f I was able to get -59 on my UHF duplexer, so much to learn

Do you mind me asking where you got the SAA-2N from? I'm wanting to upgrade my old original, just concerned whether the "fake VNA" thing is still an issue with the newer models.

I have both he H4 and the F series with metal case. The F series appears to be a better instrument, in both sensitivity and dynamic range. I found it does not get noisy until I get past the -90dB point when adjusting a single cavity, but have noticed that point wander about a little. The H-4 does not like resolving notch depths much beyond -85dB, and has a tendency to pick up extraneous signals, messing up mesaurements in the 'weak signal' range of the VNA. The TinySA is also a great tool, but takes far more patience to become proficient with it. Love the videos!

Tnx Alan!

Can dulexer be tuned with tinySA? If so pls make such a video

Hi, although exact frequency at which dip occurs can't be seen (because of low SN ratio of nanoVNA), I think that frequency at which dip occurs could be still calculated relatively precise by extrapolation of S21 curves using some curve fit algo and using S21 points in range from 0 to around -55dB (approaching from left and right side). Resulted dip is where both curves meet. It would be interesting to see how that result compares with professional VNA. (It may be even possible to get some approximation of how deep that dip is)

I have my Rigol spectrum analyzer with TG for measuring stuff but it's not really portable so I will buy one pocket sized VNA for sure some time in the future. Also these must be really great for beginners as the "real" analyzers cost at least four figures. But I also think if you really start setting up a relay station you will have to use proper measuring equipment as the material for the station by itself can be very expensive and youdon't want to go cheap on tuning.

wow you did a video

One question, can I improve the dynamic range adding a wide range LNA amplifier (20 or 30dB) in the port 21? Only to improve the noise floor and maybe the Notch peak measurement capacity. I have both, V1 and V2 NanoVNA. Thanks

@w2aew I was looking to see if you have reviewed the MINI1300 analyzer and see if it can be used to check/tune a flatpack duplexer. The mini1300 seems to be getting a lot of interest lately.

Is the reference level fixed on a nano? If it is configurable wouldn't it be possible to measure the I.L. of the pass at a reference of 0 or slightly greater, then change the reference to say -40 or so to measure the I.L. of the reject to work around the smaller dynamic range? Is the actual limitation the Noise floor or effective sensitivity? I may be unaware of how doing this would create a false measurement I'd greatly appreciate your input.

so you don't recommend the SAA-2N? I'm looking at the new nano V2 Plus4 but it's 2x the cost and 3 month wait.

Great video, thanks! What is your opinion on SDR Kits VNA for tuning duplexers? Also the new Rigol SA / VNA like the RSA3015N might be a good "low cost" option for ham repeater work. What do you think? Regards.

Fascinating. I had never considered the need of duplexer on a repeater. Knowing what you now know, is it possible, but perhaps not wise, to extrapolate the rejection curve down below the nanoVNA noise floor to simulate more resolution?

I had a feeling the noise floor was going to be the determining factor here. I have a Rigol DSA-815-TG and even wish it had a lower noise floor. Nice job on the video. I didn’t know about the SAA2.

Thank you for doing more videos on duplexer tuning. I've tuned several of these mobile notch duplexers on an HP 8920 I purchased calibrated from a well known source that provides these service monitors to mobile radio shops. With a 3Khz resolution bandwidth the best I've been able obtain is ~84db notch. The specs sheets on these units usually say something around 75db, such as resources.tessco.com/attachments/76905_633-6A-2N.pdf. So I'm confused on how you're getting 100-110db notch.

Awesome video! Have you used the Pico VNA before? it seems a bit cheaper than the Tek VNA you have at maybe similar performance?

Would it be possible to aggregate data from numerous sweeps to extend the effective dynamic range?

Hi i have the mini1300 and the vna-f, but i do like the look of the SAA-2N , can you please do more tests with it and tell us what you think of it, i have a kenwood ts2000 so i want to play with 23cms, Thanks Dave 2E0DMB

Great video. Thanks for posting. Would putting a 20 db pad inline help with the readings? I just received my NanoVNA H4 yesterday and it came through with the firmware that allows 401 sampling points. I noticed the SAA2 only had 101 sampling points. I hope they come out with new firmware that will allow up to 401 sampling points. These little guys are great. I also have the TinySA. Great for hunting down noise sources. Barry, KU3X

It's only going to get better. The cost makes it available to all of us. What's not to like.

Curious to know how the nano works in a high RF environment. For example, a repeater site with multiple megawatt ERP transmitters.

Do you know if the SAA2N has an option of 401 points too?

Hi Alan, Another great video thankyou. I was wondering if you have a video in the pipeline for checking crystal parameters With a view to make a crystal filter? Regards......Peter

Can you post a link to the firmware you mentioned that you're using with the NanoVNA H4? Thanks again for your informative videos, I look forward to all of your updates. N9PBD

Please write down on sharpe the freqs on that duplexer, i've had those little red and green wear out or fade off!

👍

Would you say the Rigol DSA 815 TG is up to this task?

Can you make a video with a paper telling the difference between Diplexers and Duplexers and examples of what both are used for to get a theory of operations on both. Why are you tuning the duplexer filters using S11 return loss? Why doesn't the NanoVNA have the definition to go all the way down to -100dB or more even if you change the scale to 20dB per division it still won't give the same results is because the front end or what in the NanoVNA is preventing this? Do you think a newer firmware update will fix this problem or its the ADC/DAC converters that is causing this issue?

Add attenuator and set offset.... improve Dynamic range....

I think the notch was a little to the right on the pro vna too, albeit not as far perhaps.

There is a Nano VNA Plus 4 with 90dB dynamic range. Please if it's possible do the same comparison with this one. It will be very interesting.

Interesting point to be aware of. I never concidered dynamic range that important. I probably won't need it for antenna matching and SWR analysis etc.?

We all know that one should use an attenuator when the input signal is too strong. I think there a similar workaround is possible: we can use an amplifier in a measurement circuit. It will not do great magic but in some cases is possible to pull the signal through a bandstop filter. Probably it should be a logarithmic amplifier that will compress the dynamic range. If we could figure out the dynamic response of that test circuit we could obtain characteristics of the filter or device. There are a lot of drawbacks but the concept seems to be possible.

Hola,¿ vna sv4401a review ? Saludos.

Hi Alan. Regarding the nanoVNA H4. I know this is an older video. I was wandering did you have in this firmware version the possibility to select bw? Maybe you don't recall it anymore... I bought a H4 about some half a year ago, and see I have pre-installed fw version @Dislord @edy555 1.1.01 from 30 Dec 2021. I have noticed on your screen CH0 and CH1 (and on mine S11 and S21 instead) and have seen on developers site they changed that from version v1.0.63 dated 30 May 2021.. Regarding the bw (in this v1.1.01) I can go as low as 30Hz. It doesn't really lower the noise floor (better dynamic range), as I have expected, compared with 1kHz (on the same range you used in this video), but rather the signal/trace is much less noisier (I have just an open CH1 connector and measuring the noise floor). Also I see you have 7.5 vertical divisions, and I have 7. I will try now to upgrade to the latest fw version v1.2.20 from 12 March 2023. Do you know by chance are there differences in fw these days for this little unit, regarding DiSlord and Hugen (as I am not an advanced user yet) and just try to understand?

Wow thank you so much, exactly what I was looking for! Can you please do a video on how to calibrate duplexer using NanoVNA. 1. To learn the process. 2. Shop won’t touch my inexpensive made in China duplexer needed for shelter repeater system. Thanks and 73 DE KK4MND

I hope soon we can have a v3 version with 100db of din range

The problem may be sample points more than dynamic range. with software you can greatly increase the number of same points. That would be a fairer comparison.

Can you tell us more on the firmware for H4 with 401 points. Tks Dan KCC4GO

I recall seeing one of those nano VNA’s that could be connected to a computer and run an open source program that gives you a desktop view so that you could have a higher dynamic range. Much like your professional unit is operating but still not as a high quality image.

Would attenuating the amount of signal to the duplexer show a better plot of where the duplexer is tuned at? TNX again for another great video! 73 N8AUM

Alan can you give a link to the SAA-2N that you purchased? --KE4EST

Can't you put an attenuator inline to stay within the dynamic range of the device?

I'm no RF engineer, but I am curious about the possibility of using the averaging of high numbers of samples to reduce the noise floor sufficiently to tune duplexers. I realize that it would seriously slow down the alignment, but I have a lot more time than I have the sort of money that a professional VNA costs. So I'd be willing to take my time with the alignment if the technique actually worked. Would it? The reason I am curious about it is because high numbers of sample averaging worked very well for digging out weak BPSK signals from my Longwave beacon transmitter, and it seems like the same sort of problem.

How are you? After a long time.

We have a TTR506A at work that I use daily and it's a fantastic device but for doing home stuff I love the NanoVNA stuff. I'm looking forward to the next V2, according to the developers on EEVblog it should be expanded up to 4GHz with a faster sweep speed too.

Some people do review about nanoVNA like this vlog

🙏🙏🙏👍🙏🙏🙏

Hello w2aew, I follow your videos for quite a long time, and I am amazed to find out that I can always learn something new from you. I wanted to contact you via private instead of writing on the comment wall, but I coudn't find such a contact on your channel, and I see that you read these comments as well. I would like to translate your videos to my own language to help the students of my former university, because not everyone speaks English there, and your videos are unique in a way that I would like to reach as many interested people as possible. I would do this for free. Translating is actually something that gives me a plenty of joy on its own. I am the main translator of the also really famous Afrotechmods channel where I have already translated 20+ videos in the past 3 years. So if you support this idea, please allow the videos to accept translations, or alternatively give me a business email where I could send you the finished subtitles (the former one would be the easier way though IMO). Thank you for reading, and keep up the great work! :Niz

Nice presentation of the nano in observing of tuning of a series of filters pass or notch. The mobile duplexer in your presentation is a notch duplexer NOT a band reject duplexer. It’s not semantics either, it’s the correct identification of the duplexer design. I disagree that the NANOVNA is not suitable for tuning the duplexer. It certainly is if you have ever tuned one and is confirmed in your video. What you cannot measure with the NANO is exact amount of notch depth but this isn’t important if the minimum point of the NANO is set to the frequency desired as notch depth and notch skirts will be properly set and tuned based on the cavity Q.

Many many years ago I had an idea to build a sine wave synthesizer which can generate all the nth harmonics of the fundamental frequency (tunable) simultaneously. The idea behind is a musical application, the effect of a plucking string, but I failed to do it. Wanted to make it all with analog technology. Can you do a video on that?

40db of additional dynamic range for 40db increase in VNA price.

If u have a few dollars invest in a Kc901s+ by DeePace. Amazing unit and can definitely tune filters easily.

Eliminated one of the units from consideration. WOW, the Tektronix unit sure is a budget buster!

Only to your information, the latest firmaware from Nano SAA-2N give us a 90dB of dinamic range...not so far from your TTR...

I'm really curious how a SV4401A would do in the same comparison. 🤔

Considering the equipment costs involved, most people cannot afford to use the professional equipment so the nano and its results are much much better than nothing at all. So the professional equipment does a better job but at what cost ???

They really need to work on instructions and nomenclature tho!

I know absolutely nothing about any of this. Yet it came across my feed and I must say, it is very interesting! Might have to look into it more.

You stated that with the Nanovna it isn't possible to adjust a duplexer for maximum performance at given frequencies within the designed operating range. I completely disagree since it is not necessary to actually "measure" the magnitude of the notch in the example of your demonstration but the position of it specturaly. The Nanovna will do this however, even though it cannot measure the magnitude of the actual notch depth, that is not important for proper adjustment. Once the notch is properly set within the center of the frequencies of the notch, that is all that is necessary since the design of the duplexer will provide maximum attenuation assuming the duplexer is properly functioning. If it isn't the nano will show this too. There are more measurements errors caused by improper field instrumentation than anything else. Moreover, a VNA for field application such as that for amateur radio requirements is super overkill since only return loss S11/S22 and transmission loss S21 are the primary parameters of interest which a scalar analyzer will provide quite accurately. Finally, the use of "Band Reject" is improper since the filters are tuned for a specific notch frequency, hence the correct name is notch duplexer, not band reject duplexer. Otherwise a very nice and informative presentation. :-)

Instead of finding good uses that these vna's are good for, it seems everybody who is testing these nanovnas want to find all the limitations where the vna is not good for. Negative outcome tests are getting old.

yeah no ish, a $100 unit wont be near the same as a $16,000 unit. lol

Well.......that Sucks ! 🫲☹️🫴 But there again like you mention ! Not a Commercial, or Professional unit, but made so the Radio Amateur may find value ! If nothing else, it may help with the understanding of the Smith chart ? Having said that, it may be reckless, but if you can get those Cans that close, especially that far down DB wise, couldn't you tune the rest by ear ? Or even call it good ? Speaking from an Amateur Radio perspective, that is !