Beware of cheap underperforming clones

As of 2023 there are many badly performing clones on the market. V2/3GHz NanoVNA uses parts like ADF4350 and AD8342 which are costly and clones have been cutting costs by using salvaged or reject parts.

See official store and look for V2 Plus4/V2 Plus4 Pro versions only to avoid getting a bad clone. We have stopped selling V2.2 versions since October 2020, so all V2 hardware that are not Plus or Plus4 are not made by us and we can not guarantee performance.

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Outdoor Vehicle Tag RFID Antenna Analyzer

PrimeBIZ ICT Solutio 2023/01/07 22:12

Can anyone help me, if this nanoVNA can be used as RFID Antenna Reader/ Analyzer for installation?

Our project is to install RFID Reader Antenna on Expressways


W0LEV 2023/01/08 16:37

1) To read the information from the tag: NO

2) To sense and register the strength of RF emissions from the reader: YES

Dave - WØLEV

On Sun, Jan 8, 2023 at 4:34 PM PrimeBIZ ICT Solution <> wrote:

> Can anyone help me, if this nanoVNA can be used as RFID Antenna Reader/
> Analyzer for installation?
> Our project is to install RFID Reader Antenna on Expressways
> Thanks

*Dave - WØLEV*

Bob W0EG 2023/01/08 12:49


On Sun, Jan 8, 2023 at 11:34 AM PrimeBIZ ICT Solution <> wrote:

Bob W0EG 2023/01/08 12:53

It will not read RFID tags. It can measure impedance of antennas.
However, not really rugged enough for professional field use.

On Sun, Jan 8, 2023 at 12:49 PM Bob Morris <> wrote:

Tom Twist 2023/01/09 07:37

Does professionals treat their equipment worse than hams?

Reinier Gerritsen 2023/01/10 17:25


The nanoVNA can be used to analyze the antenna, but it cannot read RFID
I'm an RFID specialist by profession, I could probably help you further.
If you are interested, have a look at my website for
contact details. I'm based in The Netherlands, you can use google
translate to translate the website to any language google provides. Just
to be clear, I do not work pro bono.


Op 8-1-2023 om 07:12 schreef PrimeBIZ ICT Solution:

Bob W0EG 2023/01/10 12:44

Yes, often for field workers under tight deadlines. The nanoVNA has SMA
connectors attached directly to to the circuit board. Easy to damage and
the sma connectors ware out with repeated use. Not easy to replace.
Professional equipment will typically use Type N connectors, much more
rugged. Also, better case and screen protection. And support from the
manufacturer including calibration and repair if needed. However, for the
price, you could treat the nanaVNA as a disposable.

On Tue, Jan 10, 2023 at 11:58 AM Tom Twist <> wrote:

Bob W0EG 2023/01/10 15:36

Let's be clear about one thing, the nanoVNA V2 can measure the input
impedance (VSWR, return loss, reflection coefficient) of a passive
antenna. It will not measure field strength from an antenna driven by a
transmitter.. If the antenna and RFID reader/transmitter are one combined
unit, then this instrument will not be of much use.

On Tue, Jan 10, 2023 at 12:44 PM Bob Morris <> wrote:

PrimeBIZ ICT Solutio 2023/01/11 12:38

Thank you for your reply... My requirements only is to measure and document
the range of RF Propagation from RFID Reader Antenna Sir, is it possible to
measure with nanoVNA?

On Wed, Jan 11, 2023, 12:58 AM Reinier Gerritsen <>

Hank Hamner 2023/01/11 05:54

A cheap $50 US nanoVNA with an attached antenna can measure relative signal strength of RFID signals and, if build or buy a measurement fixture, you can accurately measure many network parameters.

Read  the article on measuring signals with the nanoVNA  .  Search N5HXR NanoVNA.  I measure relative signal strength of my handhelds by attaching a homemade directional antenna.  There is no magic in RFID in that they are UHF modulatedvsignals well within the frequency range of most nanoVNAs.

If measuring strong signals start with a 30dB attenuator on the S1 port.  Attenuators are cheap.  Or,  if you want to accurately measure absolute db signal strength,  build a meter based on the AD8317 or equivalent IC.  They cost around $20 US.

Experiment with your nanoVNA.  It can do amazing things.

On Tue, Jan 10, 2023 at 11:07 PM PrimeBIZ ICT Solution < > wrote:

Dave VE3TLY 2023/01/11 07:04

To measure RF signal strength, I would recommend that you use an RF spectrum analyzer, not a network analyzer.


Hank Hamner 2023/01/12 05:37

That is a pretty broad statement. VNAs are used all the time for accurate measurements of RF power and perform many of the functions of an SA. Please see the article from titled "Spectral analysis with a vector network analyzer".

john ni0k 2023/01/12 07:46

The RSP1 with the SDR software is supposed to measure RF within 1 dB.

-de John "Curly" NI0K in rural Debs, MN USA
Hamshack Hotline: 6100000271

Dave VE3TLY via wrote on 1/11/2023 9:04 AM:

Brian Amos 2023/01/13 13:33


I browsed through this article, I didn’t study it. But it seems that some of their (Copper Mountain) vnas are capable of doing spectrum analysis, however the vna contributes to the spectrum during the measurement, so they discuss in detail how to filter out some of the noise from the VNA. Their $10,000 vna can do that,and their $40,000 vna can do that, but their $6,000 vna cannot, I would expect that measuring spectrum with our $200 vna would be very noisy, and inaccurate, if even possible. Do you have any examples of anyone using the nanoVNA2 for spectrum analysis? How is that accomplished? I’m sure it’s possible with other VNAs but since this forum is specific to the nanoVNA2, I think it’s a stretch to say that it is as capable as other units that are 50+ times the cost. I love my nanoVNA2, it’s a very useful tool for vector network analysis, but it is definitely not the same as a $10,000 analyzer. 

A $50 spectrum analyzer would be a useful tool if spectrum analysis and signal strength is the goal. And would be much more accurate than the nanoVNA2. I’m sure what VE3TLY is suggesting is that you shouldn’t use a screwdriver as a hammer. Sure it will work, but it won’t be effective. Use the right tool for the job. 

On Jan 12, 2023, at 10:39 PM, Hank Hamner <> wrote:

That is a pretty broad statement.  VNAs are used all the time for accurate measurements of RF power and perform many of the functions of an SA.  Please see the article from titled "Spectral analysis with a vector network analyzer".

On Jan 12, 2023, at 12:29 AM, Dave VE3TLY <> wrote:

To measure RF signal strength, I would recommend that you use an RF spectrum analyzer, not a network analyzer.


Bob W0EG 2023/01/13 08:55


I did see the N5HXR article. What he describes is a two-port measurement
where the antenna is driven by port 1 of the VNA and signal is captured by
a test antenna and coupled to port 2. That will work but not very
practical for a field installation. The nanoVNA is not a frequency
selective field strength meter. To see if an antenna is actually radiating
an RFID signal, a better choice would be a spectrum analyzer. The TinySA
would work for 900MHz reader.

I would ask the OP what parameter he wants to measure. Antenna SWR? Ok.
Field strength? No.

On Thu, Jan 12, 2023 at 1:29 AM Hank Hamner <> wrote:

Hank Hamner 2023/01/14 04:30


You are right in that the problem has not been carefully defined. I'm not
sure what that is.

Only then can the proper tool be obtained be it a VNA, SA or some version
of a field strength meter.


On Sat, Jan 14, 2023 at 12:23 AM Bob W0EG <> wrote:

Hank Hamner 2023/01/14 04:31

I agree!

On Sat, Jan 14, 2023 at 12:23 AM Brian Amos <> wrote:

Dave VE3TLY 2023/01/14 13:37


This has become a very interesting topic, thanks to everyone who has shared an opinion or observation. And thank you Brian, I think you have captured my thoughts very well. Here are some additional observations.

The original statement was rather vague but I assumed the author was searching for ways to evaluate an RFID system at UHF or higher. No mention was made of frequency, transmitter power level, receiver sensitivity, operating range or antenna gains. I keep a reminder in my office which is a quote from John Dewey that reads "A problem well stated is a problem half solved." It has served me very well over the years. Unfortunately I think we can all agree that the problem as stated in this thread has defocused the discussion.

I think we can assume that the root problem provided by the author is essentially to assess system performance at very low signal levels. In my experience this leads to signal levels somewhere in the -120 dBm level. With that in mind, I did some simple bench measurements today. I used an HP8640 RF signal generator (no traceable calibration) as a test signal source at 500 MHz. I monitored the signal first with a spectrum analyzer using, as mentioned by John NI0K in an earlier posting, an SDRplay RSP1A running "Spectrum Analyzer", a free application ( ). I was able to clearly measure the 500 MHz signal peak at -130 dBm. My experience with this SA is that it is remarkably accurate, likely within 1 dB. I then repeated the measurement with my NanoVNA V2 Plus4. In this case, the minimum discernible signal was approximately -30 dBm. I used the log/mag setting. If anyone can offer a better suggestion, I'd be happy to check it out. This simple experiment points to two conclusions. First the sensitivity of the SDRplay-based spectrum analyzer far exceeds that of the NanoVNA, and second, the NanoVNA is best suited for 2-port measurements using applied signals at suitable levels. I haven't seen specifications for the dynamic range of these instruments, but it sure looks like the SA gets the nod.

As far as the original query is concerned, I think there is agreement that the author might consider a solution such as a tinySA or an SDRplay and maybe should post a message on one of those forums. I wish him good luck with his project.


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