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AA version font requires a larger flash, resulting in saving the settings of
the flash address overlaps with the program flash and I will modify the aa
version later.

It eventually hung at power-on for me WITHOUT doing touchscreen calibration,
fortunately after capturing mostly legible menu screens.

Took this opportunity to exercise starbuck5250's DFU-from-Hex message:
/g/nanovna-users/message/4159

...hacked into

edy255's 0.2.2 ch.hex sadly has tiny font..

Hi,
I replaced the cables with much shorter ones, and re-calibrated using these 2 new cables (see attached photos), and I am getting the same results. Not sure the cables interfere with the nanoVNA results. As far as I remember, cables longer than wave length/8, I should worry about transmission line effects. However, in this case, the cables are 10 cm long each, and the subject frequency is 60MHz.

Hi, I am fairly new to RF and have been working in electronics as a hobby for decades, but have recently gone back to school and am working toward an engineering degree, either electrical or mechanical, not sure yet but am getting the math and physics out of the way to go either way. So please forgive any lack of understanding on my part. I am working on a project that needs me to determine the values of a coil antenna that will be used in an RFID device at 13.56MHz, I need to design an impedance matching network for the chip that will run the antenna, so I need to know the resonant frequency, inductance, and parallel resistance, does the nano measure parallel resistance? I am using the nanosaver software which has a field for Rp but the values I'm getting at resonance are very high and inconsistent, this is what I would expect if you were to measure the reactive impedance of the antenna at resonance, but the parallel resistance at resonance is effectively the radiated power of the antenna, yes? In any case, I'm a bit lost as to whether the nano isn't going to measure what I need or whether I'm asking it the wrong questions... Thanks!

Thank you for your response. During SOLT calibration, I included the two black coaxial cables, so I thought that this way, I neutralized any effect of the connecting cables. Can you please elaborate more on the right way to understand the behavior of this inductor using the nanoVNA.

Ok, ya got me. Reading the introductions to the two papers left me going, huh? But I do hope it is easy, and that you do publish a simple method.

36 : Primary AnyVNA Measurements

35 : Straight In The Heart of The Matter - 6 October 2019 :
/g/nanovna-users/message/4177
@Gary O'Neil

Hello Gary,

Well, to start from the beginning, would you clarify for us,
please, if would you unreservedly agree with us on that :

"
Primarily, anyVNA measures
( Amplitude Ratio , Phase Difference )
couples in terms of
Frequency
"
?

Regards,

gin&pez@arg

36

It would seem sensible to add a reciprocal command if at all possible.

Particularly if NanoVNA-H V2 may have no touch screen
or is controlled via BlueTooth or USB from mobile devices
(as now by WebUSB app with recent Android versions)

On Sun, Oct 6, 2019 at 10:49 AM, <erik@...> wrote:

no reciprocal command to upload data from the PC to the nanoVNA

It would seem sensible to add a reciprocal command if at all possible.

Anything to avoid having to physically manually enter long sequences is very desirable, especially as it's only possible to retain a small number of configurations internally.

The ability to reload (or clone) settings when new firmware is installed or the memories are wiped would also be handy.

Regards,

Martin - G8JNJ

Please have a look at the firmware.
The "save" command saves the internally measured calibration data to the internal save location [0-4], recall is the reciprocal command to load calibration data from the internal save location.
The "save" command does NOT upload calibration data from outside the nanoVNA into the nanoVNA
The "data" command downloads data from thenanoVNA to the PC, there is no reciprocal command to upload data from the PC to the nanoVNA

you're measuring your inductor through two transformers (coax cables). So, the capacitance shown on the display of NanoVNA is capacitance on the cable input, but not on the inductor. When you connect unmatched circuit on the end of coax cable, the coax cable starts to works as RF transformer. It transforms impedance. Read about transmission lines...

30 : our final report 1
33 : the mathematical expressions

[ for the sake of completeness of the topic, the contents of this
[ message are just a repetition of the following two 2 messages:
[ 4 October 2019 : /g/nanovna-users/message/3989
[ 5 October 2019 : /g/nanovna-users/message/4068
[ which we wrongly sent outside of this topic
[ -
[ please accept our apologies

30 : our final report 1

29 : ann : our nanovna will be evaluated tonight :
/g/nanovna-users/message/3867

hello all,

this is our final report on the comparison of our
[nanovna] and [vna] in terms of frequency

1 : for nominal values without uncertainty :

red : nanovna - blue : vna

r :
x :

after all that said, accept, please, our humble - but sincere - congratulations

sincerely yours,

gin&pez@arg

30

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

33 : the mathematical expressions

hello,

allow us, please, to emphasize that the mathematical
expressions we used for:

30 : our final report 1 - 4 Oct 2019
/g/nanovna-users/message/3989

are just those mentioned at:
16 : 27 September 2019
/g/nanovna-users/message/3161

that is the ones shown at:


sincerely,

gin&pez@arg

33
30

Hi,
I received my nanoVNA a couple of weeks back, and since then, I am trying to improve my understanding of RF and basic concept using this wonderful tool.
I am trying to understand the behaviour of an inductor that I plan to use as a chocke for an RF amplifier. I wound the inductor over an FT23-43 ferite core, and mounted it in an S21 mode as seen in photo "DUT FT23-43 Inductor".
I used nanoVNA Saver excellent application to sweep from 50KHz to 300MHz, and included the output S2P file "13uH FT23-43 Ferrite Inductor".

Out of this test, I got multiple questions around basic RF concepts I wish I can find answer for it from more experienced group members:

1) From the S11 smith chart (photo nanoVNA S11 Smith S21), and from the nanoVNA Saver displays, I see that the inductor turns into capacitor around 42MHz onward. I would expect this due to inter winding capacitance. However, I would expect that the S21 attenuation starts to reduce as we go beyond this frequency. However, I see that the S21 attenuation remains constant at -21db till 300Mhz. How come?

2) As I understand it, -21db is around 1/100 of power attenuation. I made an oscilloscope setup (photo nanoVNA S21 CW 60MHz Osc Connected) to see what is actually going on. Introducing the oscilloscope measurement does not seem to affect the reading as at CW=60MHz, it shows still -21dB of attenuation.
Looking at photo "Oscilloscope", I see a voltage attenuation of 20.
I thought that -21db expressed in voltage as a drop of 1/10 requires same input and output impedance, which is not the case. The input impedance at 60MHz is 972.37-j398.09 while the output impedance is 50Ohm of the S21 port of the nanoVNA. Any idea what is going on?

35 : Straight In The Heart of The Matter

@Gary O'Neil - 6 October 2019:
/g/nanovna-users/message/4169

Hello Gary,

Well, to put it simply : in our small world, your
last message sounds really Great ! Thank you
very much; indeed.

OK then. But, it would take some time, in order
to reply you - in a sequence of parts, of course.
Therefore, please, stay tuned.

Kind regards,

73

nikolitsa oe3zgn|sv7dmc & petros oe3zzp|sv7bax @ arg iaoi nfi

35

Pretty sure nanovnasharp does this.
Tried decompiling the thing but im no coder so all i found was this
private void save0Button_Click(object sender, EventArgs e)
{
this.controller.SendDataToCom("save 0\r\n");
this.saveGroupBox.Visible = false;
this.stateGroupBox.Visible = true;
this.responseGroupBox.Visible = true;
this.languageGroupBox.Visible = true;

with save 0 to 4
and then recall 0 to 4

All working well.
I merged the edy555 additions with my modified scan command and made the build firmware available in the firmware section.
Build 0.2.2_1
/g/nanovna-users/files/Firmware/NanoVNA%20firmware%20build%20by%20Erik
Usage (assuming your SI5351 supports up to 250MHz):
threshold 250000000
saveconfig
Remember to do a saveconfig after updating the threshold otherwise the setting will be lost after reset

Hello,

This email message is a notification to let you know that the following files have been uploaded to the Files area of the [email protected] group.

• /Firmware/NanoVNA firmware build by Erik/Release 0.2.22_1 with modified scan command and harmonic threshold setting.zip

Uploaded By: erik@...

Description:
Release 0.2.2_1 from edy555 with modified scan command to be compatible with TAPR VNA software for PC allowing unlimited scans and added harmonic threshold command Usage: threshold 250000000 saveconfig Without saveconfig the updated threshold will be lost after reset

Cheers,
The Groups.io Team

On Sat, Oct 5, 2019 at 07:21 PM, W5DXP wrote:

Where does it tell how to hook those 4 wires up to a NanoVNA? NRST->RST?
TCK->SWCLK? TMS->SWIM? GND->GND? How about SWDIO on the ST-link?

ST-LINK uses just 2 wires: SWDIO and SWCLK.
Also you're needs to connect VDD to 3.3V and GND to GND.

You can also connect 5-th wire RST to RST, but it is required only when SWD pins are reprogrammed in firmware. NanoVNA doesn't use SWD pins, so you can connect with STLINK with no need for RST connection.

Here's what can happen:

Someone has an eBay account and they decide they want to make some quick money from it. Or they hijack an account for the same reason.

So they'll sell something at a "price that's too good to be true." They sell a bunch of an item that they're never going to ship out. And they set it up so that there's a long time before you're supposed to get it. They are counting on at least some buyers forgetting about it until it's too late to ask for a refund. They get as much money as they can out of their PayPal account before they're caught and shut down.
And in many countries a few hundred dollars goes a long way! Often they don't need to get many buyers to make good money for themselves.
It sounds like that's what this is. So make sure that you don't forget to make a claim against it when the time comes that you can.

For something suspicious like this I usually put it in my calendar on my phone, set to a date a couple of months in the future with a notification that reminds me to check on it. I was duped once, but now I set a notification in the future so I don't forget.

I use the stylus from Galaxy Note phone...never did use it with the phone.