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Re: Nanovna H4 #nanovna-h4

 

I was using NanoVNA-Saver to try to use the VNA on my computer. I have since learned that it is probably less hassle to just use the NanoVNA. Thanks for the response and I have a very bad habit of asking questions without putting enough info in. Will try to do better.

Sent from Mail ( ) for Windows

*From:* VE3WNA John ( john.verne@... )
*Sent:* Thursday, June 16, 2022 7:43 PM
*To:* [email protected]
*Subject:* Re: [nanovna-users] Nanovna H4 #nanovna-h4

On Thu, Jun 16, 2022 at 03:08 PM, Mike McKinney wrote:

first time trying to use the nanovna H4. Not sure how to correct this error.
Any help would be greatly appreciated.
You should tell us what you were doing at the time, and how. This looks like you were connecting with some desktop software, probably over USB, but we are guessing.


Re: NanoVNA for RFID design

 

I have about 100 used CGM I've absconded from my wife's bi-weekly usage (diabetic). TI has all sorts of info on line free for the downloading. See the pic attached for a sample. I can give out several just for the asking, except for the cell (Post Office is funny about that stuff) I've also attached the TI pdf. Have fun.

Mike C.

(Sand Mtn, GA)

On 6/15/2022 3:50 PM, Chuck, KF0CT wrote:
Thank you

________________________________
From:[email protected] <[email protected]> on behalf of Jim Lux<jim@...>
Sent: Wednesday, June 15, 2022 6:45 PM
To:[email protected] <[email protected]>
Subject: Re: [nanovna-users] NanoVNA for RFID design

On 6/15/22 9:39 AM, Chuck, KF0CT wrote:
But why would anyone want an RFID reader that can read cards over 10" away except to read someone's Credit card or Debit card without the person knowing about it... then you just watch them type in their pin number and you have complete access to their credit/debit card....

____________________
A good use case is where you use the badge to authenticate into a
computer (using an actual contact badge reader that uses the
cryptographic chip in the badge), but then just need to make sure that
the user is in the vicinity. If you require the badge to be resident in
the computer, it makes it hard to use multiple computers at the same time.

A typical PIV-II credential has both an RFID (which returns only the
serial number of the badge) and an actual chip (like in a credit card).



ISO14443A/B ISO ISO15693 are two of the specs


ISO/IEC 15693 systems operate at the 13.56 MHzfrequency
<>, and offer maximum read
distance of 1¨C1.5 meters

They do both ASK and FSK.



As far as NanoVNAs go, it's a useful tool to develop and test these kind
of systems - 13.56 MHz is easily choked with ferrites to remove the
cables and instrument from interacting with the system. So you can set
up a test card (which has the antenna, but a SMA or MMCX connector on
it) and a test reader (just the antenna, with connector). And this is
at a frequency for which the NanoVNA is perfect. You can easily set up
a scripted environment, have a user wearing the badge on a neck lanyard
and move around while logging S21.











Re: sd card - fail write

 

Hi,

This is a true case of one market segment impinging on another.

For years,there has been a market push for faster SD cards with higher capacities for cameras or phones, for example.

Many microSD/TF card users do not need even 8 Gb of storage (single board computers, firmware upgrades) and these devices sometimes cannot support the faster, higher density card.

In general, most cards never get used to high capacity or reach R/W failure. As such, I generally purchase 8/16 Gb cards at the low end of the price range and always keep 8 to 10 new ones in a drawer for immediate use.

(Some Chinese sources are now providing Terabyte cards¡­)

Larry
AC9OX


Re: Nanovna H4 #nanovna-h4

VE3WNA John
 

On Thu, Jun 16, 2022 at 03:08 PM, Mike McKinney wrote:


first time trying to use the nanovna H4. Not sure how to correct this error.
Any help would be greatly appreciated.
You should tell us what you were doing at the time, and how. This looks like you were connecting with some desktop software, probably over USB, but we are guessing.


Re: Bogus Request for Link Change

VE3WNA John
 

On Thu, Jun 16, 2022 at 03:08 PM, Russ Woodman wrote:


I'm assuming this is bogus but could someone confirm the legitimate site for
NanoVNA?

From edelswartz123@...:
Hi, I just noticed the "NanoVNA" link on your page:

points to an unofficial website (nanovna.com) that has been selling bad
clones, so would you mind pointing it to our new website
() (I am a developer there) instead?
I received a similar email about a blog entry I made about the H4 I picked up. I updated the link to refer to the place I purchased it, rather than nanovna.com, but I'm not sure if that was even warranted. No doubt there has been a lot of history related to the somewhat, sorta, open source hardware and so-called "clones", but that cat is out of the bag now.

The real challenge for folks is knowing what the are buying to some extent. The whole NanoVNA market is a huge caveat emptor, though I think if you choose to buy from one of usual suspects and stay away from websites that start with the letter "a" you might be ok. That might not satisfy "edelswartz" though.


Re: Nanovna H4 #nanovna-h4

 

Please update the firmware of your nanovna.


Re: Bogus Request for Link Change

 

In fact nanorfe violates the GPL license and publishes a lot of false information, please remember that nanovna.com is the only legitimate website.


Re: Bogus Request for Link Change

 

Andreja,

Thanks for the info. Seems like it might be useful to link to both of them.

Russ, K5TUX

On Jun 16, 2022, at 2:43 PM, Andreja YU1NKA/DM1NKA <andrejakostic@...> wrote:

?Well, the short story is that it's not as bogus as it seems, but it also
gets really messy really quickly.
Basically, there was the "original" version of the NanoVNA by Edy55 , and
after some time, a Chinese version appeared. Apparently, there was some
work done by Hugen and by OwO on the Chinese version. The Chinese version
became popular,m spread around Chinese e-commerce websites, and then "fake"
Chinese versions appeared as well. Then, work on improved versions started,
and there was quite a bit of drama between Hugen and OwO about who stole
what, and dumping prices and so on. I, personally, do not know the exact
details, and can't say who is right and who is wrong.

What happened afterwards, is that there's a whole bunch of "NanoVNA"
devices, and the term became a bit diluted, so if someone is trying to buy
a "regular" NanoVNA, it's very difficult to identify what the device
actually does.
Then, there's a new generation of "improved" devices, like the Hugen's
NanoVNA-H and the OwO's NanoVNA V2, and there's even a NanoVNA-F and so on.

Now, the site you link to sells what appears to be NanoVNA-H, while the
is the site for the NanoVNA V2.

All the best,
Andreja YU1NKA/DM1NKA

§é§Ö§ä, 16. ?§å§ß 2022. §å 21:08 Russ Woodman <k5tux@...> ?§Ö §ß§Ñ§á§Ú§ã§Ñ§à/§Ý§Ñ:

I'm assuming this is bogus but could someone confirm the legitimate site
for NanoVNA?

From edelswartz123@...:
Hi, I just noticed the "NanoVNA" link on your page:

points to an unofficial website (nanovna.com) that has been selling bad
clones, so would you mind pointing it to our new website
() (I am a developer there) instead?
Thanks!

-- 8< --
Thanks,
Russ - K5TUX









Re: Bogus Request for Link Change

 

Well, the short story is that it's not as bogus as it seems, but it also
gets really messy really quickly.
Basically, there was the "original" version of the NanoVNA by Edy55 , and
after some time, a Chinese version appeared. Apparently, there was some
work done by Hugen and by OwO on the Chinese version. The Chinese version
became popular,m spread around Chinese e-commerce websites, and then "fake"
Chinese versions appeared as well. Then, work on improved versions started,
and there was quite a bit of drama between Hugen and OwO about who stole
what, and dumping prices and so on. I, personally, do not know the exact
details, and can't say who is right and who is wrong.

What happened afterwards, is that there's a whole bunch of "NanoVNA"
devices, and the term became a bit diluted, so if someone is trying to buy
a "regular" NanoVNA, it's very difficult to identify what the device
actually does.
Then, there's a new generation of "improved" devices, like the Hugen's
NanoVNA-H and the OwO's NanoVNA V2, and there's even a NanoVNA-F and so on.

Now, the site you link to sells what appears to be NanoVNA-H, while the
is the site for the NanoVNA V2.

All the best,
Andreja YU1NKA/DM1NKA

§é§Ö§ä, 16. ?§å§ß 2022. §å 21:08 Russ Woodman <k5tux@...> ?§Ö §ß§Ñ§á§Ú§ã§Ñ§à/§Ý§Ñ:

I'm assuming this is bogus but could someone confirm the legitimate site
for NanoVNA?

From edelswartz123@...:
Hi, I just noticed the "NanoVNA" link on your page:

points to an unofficial website (nanovna.com) that has been selling bad
clones, so would you mind pointing it to our new website
() (I am a developer there) instead?
Thanks!

-- 8< --
Thanks,
Russ - K5TUX






Re: sd card - fail write

 

Tim, please search this forum for "SD card". You will find many users have
had the same issue, with many responses given. The bottom line is that not
all SD cards are compatible with the nanovna, and there is not an easy way
to know which ones are and are not. The card needs to support the SPI
mode. Many newer, faster cards do not; many slower cards do.

I have found that the Patriot cards labeled with class 10, HC, I, and U1
work; mine are 16GB. Other users have found others that work.

On Thu, Jun 16, 2022, 12:08 PM VE3VTH <ve3vth@...> wrote:

Hello I have installed a micro sd card in my NanoVNA-H 4 and when I try to
save a screenshot, I get a message: fail write. This is a new 32gb sd card
and it shows as fat 32 when I read it in Windows 10.
I would appreciate any help to get the card to save data. 73 Tim VE3VTH






sd card - fail write

 

Hello I have installed a micro sd card in my NanoVNA-H 4 and when I try to save a screenshot, I get a message: fail write. This is a new 32gb sd card and it shows as fat 32 when I read it in Windows 10.
I would appreciate any help to get the card to save data. 73 Tim VE3VTH


Nanovna H4 #nanovna-h4

 

first time trying to use the nanovna H4. Not sure how to correct this error. Any help would be greatly appreciated.


Bogus Request for Link Change

 

I'm assuming this is bogus but could someone confirm the legitimate site for NanoVNA?

From edelswartz123@...:
Hi, I just noticed the "NanoVNA" link on your page:

points to an unofficial website (nanovna.com) that has been selling bad clones, so would you mind pointing it to our new website
() (I am a developer there) instead? Thanks!

-- 8< --
Thanks,
Russ - K5TUX


Re: NanoVNA for RFID design

Larry Martin
 

Hello tjackson382000.

10 inches is a stretch for ISO15693, but out of the question for ISO14443. I like the Feig CPR74, which puts out 250 mW. It's a module with onboard antenna and a u.fl for off-board. Feig also has higher power (and higher priced) external antenna HF readers that will make your 10 inch distance a lot more doable. Their 100x100 mm antenna works great.

I have built 24 inch across conveyor systems with Feig's older readers that put out only 100 mW, so your requirement is not a pipe dream. Your should try to physically match the sizes of the reader and tag antennas, so your 3 inch tag would talk best with a reader antenna of 2 to 4 inches or so. With a bigger antenna, your tag might only read at the corners.

I am not aware of NanoVNA computing a Q value for you. If it did, you would still have to question whether their method matched that of the appnote. I would concentrate on computing Q per the appnote's methodology, given the profile of the Channel 0 LOGMAG curve, which is yellow by default.

One fun trick I "invented" is to connect a nonresonant loop to port 0, about the same size as my tag. LOGMAG 0 should be flat across the stimulus range. Now put your tag on there. You will see the tag's resonant frequency and get a relative indication of its Q, which lets you compare tags to see which are stronger.


Re: NanoVNA for RFID design

 

In the early days right "off The Hill" we had both 915 MHz and 2.45 GHz
passive (beam powered) and active (coin battery) tags. The present-day SAW
RFID tags are beam "powered". That was developed after AMTEK had our swing
at the market.

Yes, large coils would get you the range you desire for the LF tage.

Dave - W?LEV

Dave - W?LEV

On Thu, Jun 16, 2022 at 12:49 PM Reinier Gerritsen <
r.gerritsen@...> wrote:

It is no problem to read 10" with 125 KHz or 13.56 MHz, but you'll need
large antennas. I'm not aware of any (passive) 2.45 GHz RFID system on
the market now. Had a Motorola system long time ago.
Reinier

Op 16-6-2022 om 01:53 schreef W0LEV:
If you need 10"+ reliably, use the 950 MHz or 2.45 GHz system at lower
power, not these inductively coupled systems.

Dave - W?LEV

On Wed, Jun 15, 2022 at 5:04 PM Tim Dawson <tadawson@...> wrote:

Things like automated package/baggage sorting use RFID at times, and
distances to objects on a moving belt canrequire this kind of reach.

- Tim

On June 15, 2022 11:39:33 AM CDT, "Chuck, KF0CT" <chu_r@...>
wrote:
But why would anyone want an RFID reader that can read cards over 10"
away except to read someone's Credit card or Debit card without the
person
knowing about it... then you just watch them type in their pin number
and
you have complete access to their credit/debit card....
________________________________
From: [email protected] <[email protected]> on behalf of
tjackson382000 <tedj1@...>
Sent: Tuesday, June 14, 2022 8:20 PM
To: [email protected] <[email protected]>
Subject: [nanovna-users] NanoVNA for RFID design

I'm sure that at least a few here are familiar with the following
section
from the STMicro application note "AN4974: Antenna matching for
ST25R3911B/ST25R391x devices", since it calls for the use of a VNA and
the
ST25R391x is an RFID reader chip, supporting several standards. What I'm
confused about is line 4. And I'm not sure of the nanoVNA setting for
line
5 (Q factor measurement). Can anyone brief me on what the author is
saying
there exactly? I'm by now familiar with the open/short/50ohm
calibration
procedure of course, but intermediate level in re-exploring the many
curvy
zen mysteries of... the dreaded Smith Chart and applying the procedures
within AN4974.
Also, does anyone here have actual experience with the design of reader
impedance matching and tag antenna design for those chips? In other
words,
has anyone ever survived AN4974 and lived to tell about it? Finally, I
need to design an RFID system (I chose the ISO-15693 standard for its
relatively long range, although I would LOVE to hear about any other
standard for which cheap front end chip solutions exist). Requires a 3"
diameter tag antenna and any diameter below 5.5" for the reader antenna
and
a read range of up to 10" and must merely read out its unique UID code
when
detected. Am I dreaming? Sound feasible? Many thanks to anyone who
might
be willing to offer a little experience and advice, and I'd discuss
compensation if an expert is willing.

7.3 Verification of the Q factor in the frequency domain

The Q factor can be measured using a vector network analyzer and an
ISO10373-6 Class 1-3 calibration coil. The following steps should be
carried out:
1. The network analyzer shall be calibrated for a frequency sweep from
about 10 to 20 MHz
2. S11 measurement in log mag format shall be displayed.
3. The calibration coil is connected to the VNA.
4. ¡°Short¡± calibration of the coil and conversion to ¡°Z: Reflection¡±
5. Set marker 1 and enable the bandwidth/Q factor measurement
6. Place the PCD antenna on the measurement coil Note: If the reader is
plugged and powered, ensure that register 0x27 is set to 0xFF to avoid
an
high power transfer to the VNA ports, which can damage the VNA.
7. Adjust the suitable trim value via the register map (register 0x21)
in
the GUI of the reader
8. Place a 3 ? resistor between the RFO pin to simulate the chip
resistance during operation.
9. Press ¡°max search¡± to align the marker on the resonance frequency
peak
of the PCD antenna Figure 33 shows the results of such a measurement.
#applications #coils #design #matching #nanovna









--
Sent from my Android device with K-9 Mail. Please excuse my brevity.





--
IDcircuits - RFID & Electronics
Het Halster 40
6581 JL Malden
The Netherlands
+31 633702492
www.idcircuits.com
r.gerritsen@...






--
*Dave - W?LEV*
*Just Let Darwin Work*


--
Dave - W?LEV


Re: NanoVNA for RFID design

 

It is no problem to read 10" with 125 KHz or 13.56 MHz, but you'll need large antennas. I'm not aware of any (passive) 2.45 GHz RFID system on the market now. Had a Motorola system long time ago.
Reinier

Op 16-6-2022 om 01:53 schreef W0LEV:

If you need 10"+ reliably, use the 950 MHz or 2.45 GHz system at lower
power, not these inductively coupled systems.

Dave - W?LEV

On Wed, Jun 15, 2022 at 5:04 PM Tim Dawson <tadawson@...> wrote:

Things like automated package/baggage sorting use RFID at times, and
distances to objects on a moving belt canrequire this kind of reach.

- Tim

On June 15, 2022 11:39:33 AM CDT, "Chuck, KF0CT" <chu_r@...>
wrote:
But why would anyone want an RFID reader that can read cards over 10"
away except to read someone's Credit card or Debit card without the person
knowing about it... then you just watch them type in their pin number and
you have complete access to their credit/debit card....
________________________________
From: [email protected] <[email protected]> on behalf of
tjackson382000 <tedj1@...>
Sent: Tuesday, June 14, 2022 8:20 PM
To: [email protected] <[email protected]>
Subject: [nanovna-users] NanoVNA for RFID design

I'm sure that at least a few here are familiar with the following section
from the STMicro application note "AN4974: Antenna matching for
ST25R3911B/ST25R391x devices", since it calls for the use of a VNA and the
ST25R391x is an RFID reader chip, supporting several standards. What I'm
confused about is line 4. And I'm not sure of the nanoVNA setting for line
5 (Q factor measurement). Can anyone brief me on what the author is saying
there exactly? I'm by now familiar with the open/short/50ohm calibration
procedure of course, but intermediate level in re-exploring the many curvy
zen mysteries of... the dreaded Smith Chart and applying the procedures
within AN4974.
Also, does anyone here have actual experience with the design of reader
impedance matching and tag antenna design for those chips? In other words,
has anyone ever survived AN4974 and lived to tell about it? Finally, I
need to design an RFID system (I chose the ISO-15693 standard for its
relatively long range, although I would LOVE to hear about any other
standard for which cheap front end chip solutions exist). Requires a 3"
diameter tag antenna and any diameter below 5.5" for the reader antenna and
a read range of up to 10" and must merely read out its unique UID code when
detected. Am I dreaming? Sound feasible? Many thanks to anyone who might
be willing to offer a little experience and advice, and I'd discuss
compensation if an expert is willing.

7.3 Verification of the Q factor in the frequency domain

The Q factor can be measured using a vector network analyzer and an
ISO10373-6 Class 1-3 calibration coil. The following steps should be
carried out:
1. The network analyzer shall be calibrated for a frequency sweep from
about 10 to 20 MHz
2. S11 measurement in log mag format shall be displayed.
3. The calibration coil is connected to the VNA.
4. ¡°Short¡± calibration of the coil and conversion to ¡°Z: Reflection¡±
5. Set marker 1 and enable the bandwidth/Q factor measurement
6. Place the PCD antenna on the measurement coil Note: If the reader is
plugged and powered, ensure that register 0x27 is set to 0xFF to avoid an
high power transfer to the VNA ports, which can damage the VNA.
7. Adjust the suitable trim value via the register map (register 0x21) in
the GUI of the reader
8. Place a 3 ? resistor between the RFO pin to simulate the chip
resistance during operation.
9. Press ¡°max search¡± to align the marker on the resonance frequency peak
of the PCD antenna Figure 33 shows the results of such a measurement.
#applications #coils #design #matching #nanovna









--
Sent from my Android device with K-9 Mail. Please excuse my brevity.





--
IDcircuits - RFID & Electronics
Het Halster 40
6581 JL Malden
The Netherlands
+31 633702492
www.idcircuits.com
r.gerritsen@...


Re: NanoVNA for RFID design

 

On 6/15/22 4:47 PM, W0LEV wrote:
Yep! That's in an MF ISM band. If one has a Metcal soldering implement,
it also operated in this band. Those having a TinySA, this offers an easy
"target" for checking MF operation.

Dave - W?LEV

There are a variety of apps for phones that will interrogate the card and read it back. You can watch the activity on the TinySA.


Re: |S11| > 1

 

Bob Witte wrote the referenced book due to the requirement of EMC testing.
Any accredited lab must present measurement uncertainty of the lab in any
RE test report. Without that, the report is not accepted.

Dave - W?LEV

On Wed, Jun 15, 2022 at 11:55 PM Frank K4FMH <frankmhowell@...> wrote:

Chuck,

Take a read of Bob Witte¡¯s measurement equipment books, written when he
was at HP. Joe Carr¡¯s tests and measurements book is another one rendering
a cogent treatment of measurement errors without going very deep into the
statistical deep-end. This work is based upon formal true-score theory: the
central issue of which is whether the observed score¡¯s errors are
correlated with the true score and/or the observed score.

73,

Frank
K4FMH





--
*Dave - W?LEV*
*Just Let Darwin Work*
--
Dave - W?LEV


Re: |S11| > 1

 

Frank:
Thanks for the tip about Bob Witte¡¯s books.
Chuck KF8TI

On Jun 15, 2022, at 7:55 PM, Frank K4FMH <frankmhowell@...> wrote:

Chuck,

Take a read of Bob Witte¡¯s measurement equipment books, written when he was at HP. Joe Carr¡¯s tests and measurements book is another one rendering a cogent treatment of measurement errors without going very deep into the statistical deep-end. This work is based upon formal true-score theory: the central issue of which is whether the observed score¡¯s errors are correlated with the true score and/or the observed score.

73,

Frank
K4FMH





Re: |S11| > 1

 

Chuck,

Take a read of Bob Witte¡¯s measurement equipment books, written when he was at HP. Joe Carr¡¯s tests and measurements book is another one rendering a cogent treatment of measurement errors without going very deep into the statistical deep-end. This work is based upon formal true-score theory: the central issue of which is whether the observed score¡¯s errors are correlated with the true score and/or the observed score.

73,

Frank
K4FMH