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If you ignore the phase any signal presented at port 2 should be mixed with the CLK2 and create some response.
As a test I applied a 10MHz -50dBm signal. This resulted in the first measurement.. You see the double peak,each about 2kHz wide, caused by the mixing with CLK2 and the single frequency FFT at +/-5kHz on top of the noise like hump of about 48kHz wide. The 48kHz is related to the sampling rate of the ADC. If you increase the sampling rate the hump widens proportionally

When removing the test signal the noise floor is flat at -90dB, excellent clean signal!

With a 0dBm test signal you get the second measurement. Basically the same picture and no compression underpinning the huge dynamic range of the SA612 and the ADC.

But what is causing the "noise" hump under the two peaks?
This becomes obvious when zooming in as can be seen in the third measurement.
The emerging pattern is spectral bleeding in the FFT you get when you do not apply a good window function and the input signal is not perfectly aligned in a multiple of full cycles. So it is in reality a consequence of the test signal not being exactly matched with the mixer LO and the FFT size. Not a problem when doing regular VNA measurements because then the alignment is perfect by design.

So all is understood now and we can test a 20MHz wide scan and see if we get a nice single peak at 10MHz. This resulted in the fourth measurement scanning with 1000 points so each "dot" is 10kHz apart
The 10MHz peak is there, somewhat lower due to not perfectly fitting into one of the 2kHz wide frequency samples, scanning only 5MHz would have solved that problem.
But there are many many more peaks around 30dB lower then the 10Mhz signal. Removing the input signal gives a nice clean noise floor with no peak above -75dBm. The peaks you get are all result of all kind of harmonics of CLK2 and the input signal mixing in various modes. a real spectrum analyzer does not have this problem because of the LO/IF choice and the various filters

So, yes, you can use the NanoVNA as a spectrum analyzer but you have to know very well what you are doing and how to interpret the measurement.

hi i can't upgrade my nanovna on win10 x64

see picture

the message is:

THIS FILE DOESN'T HAVE CORRECT FORMAT
???????
ty

You need to use the V 1.03,it's ok for me on W10 x64

the V1.01 no work on win10

Ooops, too early in the morning here.
My eyes followed the time to the right of the defs and I saw 200 to the left and 'mS' kinda stuck.....

Where's my coffee!!!

At least in the source code version I have, it is defined as 200 system
ticks - which, going by the comments in the code, should be about 20ms.
That shouldn't create a problem in and of itself.

--
Rune / 5Q5R

Rob,
I just had a look at the code - debounce is defined as 200mS which I think is the culprit.
I think if someone could build the F/W with a debounce of 100mS (or 75mS?), that would solve the problem.

Regards,
Larry

On Mon, Sep 9, 2019 at 01:46 AM, Kurt Poulsen wrote:

I wonder if this 60ps delay is common to all the nanoVNA clones

60 ps is about one cm so it seems some calibration problem

On Mon, 9 Sep 2019 at 10:53, David J Taylor via Groups.Io <gm8arv=
[email protected]> wrote:

What a great range of low-cost, hand-held
counters, power meters and RF sniffers we can now buy!

Cheers,
David

HP/Agilent have made a few instruments over the years that combine the
functionality of several instruments into the one box.

Your comment got me thinking about the possibility of making a piece of kit
that contains the functionality of several things in the one box. A
frequency counter and meter meter designed for low power can share the same
RF connector.

Anyway, my first priority is to get mine in a case with N connectors. I had
not given it any thought until today but actually integrating a
calibration kit into the same box is technically doable, although the
instrument would like a porcupine if there was male and female SMA
standards and male and female N standards. But there would be no chance of
mislaying a bit of the calibration kit.

--

Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales.
Company number 08914892.
Registered office:
Stokes Hall Lodge,
Burnham Rd,
Althorne,
Chelmsford,
Essex,
CM3 6DT,
United Kingdom

From: Merlin Fox

Max MAX001S IP67 Rated Accessory Tool Box

Amazon's demand algorithm at play I guess! Even worse on ebay :(
=======================

I decided to go for two of the bigger boxes (MAX002S) as I have more kit which can then be fitted in. What a great range of low-cost, hand-held counters, power meters and RF sniffers we can now buy!

Cheers,
David
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

On Sun, Sep 8, 2019 at 11:04 AM, David J Taylor wrote:

Max MAX001S IP67 Rated Accessory Tool Box

Amazon's demand algorithm at play I guess! Even worse on ebay :(

Hi Tom
I get my nanoVNA to day. In the coming week I will measure the empty cap against my HP85033C calibration kit a let you know.
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af Tom VA7TA
Sendt: 9. september 2019 06:38
Til: [email protected]
Emne: Re: [nanovna-users] nanoVNA Real Resistance Measurement Range

Hi Erik,

Wow - great analysis! Your conclusion pinpointed the OPEN test deviation precisely! When I did the initial calibration I had not yet decided to document the testing. Then after deciding to document I needed to go back to get the OSL test results in order to generate documentation and in my haste for the OPEN test I forgot to put the empty BNC connector on. I noticed my fumble after I posted the results, went back in to edit the message and discovered if I changed anything the message would be resent to everyone. I decided the change wasn't significant enough to justify the churn. I have attached the revised OPEN files here.

I wonder if this 60ps delay is common to all the nanoVNA clones or if mine happens to be unique.

The measurement of high Z seems to be a common limitation. I have a third antenna analyzer that only goes up to 100 MHz and it shows my 1K load as roughly 500-j500. At 100 MHz the nanoVNA shows it relatively close at about 910-j250. The EU1KY analyzer seems to calibrate out the capacitive reactance at 450 MHz (930 to 1010 +/- j30) much better than the others.

Thanks for your interest!
Tom, VA7TA

Hi Salil,
I'm missing the measurement units in your diagram.

Hi Salil,

Tested your new script and it is working, I just modified a few things for my own preference.
And I use 'ax1.set_xlabel' instead of 'plt.xlabel' to have xlabel displayed.

neb

Hi Erik,

Wow - great analysis! Your conclusion pinpointed the OPEN test deviation precisely! When I did the initial calibration I had not yet decided to document the testing. Then after deciding to document I needed to go back to get the OSL test results in order to generate documentation and in my haste for the OPEN test I forgot to put the empty BNC connector on. I noticed my fumble after I posted the results, went back in to edit the message and discovered if I changed anything the message would be resent to everyone. I decided the change wasn't significant enough to justify the churn. I have attached the revised OPEN files here.

I wonder if this 60ps delay is common to all the nanoVNA clones or if mine happens to be unique.

The measurement of high Z seems to be a common limitation. I have a third antenna analyzer that only goes up to 100 MHz and it shows my 1K load as roughly 500-j500. At 100 MHz the nanoVNA shows it relatively close at about 910-j250. The EU1KY analyzer seems to calibrate out the capacitive reactance at 450 MHz (930 to 1010 +/- j30) much better than the others.

Thanks for your interest!
Tom, VA7TA

Unfortunately, I've since trashed all the related "stuff" and will not trust my memory ... However, I thought Hugen had set up a contact to deal with us english only speaking folks ...

regretfully, Jim

Hi Larry, et. al.,

You were right.? It happens in ui.c (static int Btn_check(void))
starting on line 121.? So it looks to me like you have the problem
figured out.? The jog switch was something added to eddy555's design,
but it appears to be in his code as well as NanoVNA-H.

Thanks for the words of warning on calibrating the touchscreen. I
haven't actually used the touchscreen; I thought it was dumped for the
switch, to save money.? My NanoVNA is at school, and I'm at home, so I
can't try anything right off.

Again, thanks!

Rob

--
Rob Frohne, Ph.D. P.E.
E. F. Cross School of Engineering
Walla Walla University
100 SW 4th Street
College Place, WA 99362
(509) 527-2075

Thanks Larry, for responding!? It felt the same to me.? I'll have to dig
into the source code and see what is happening.? I kind of wanted to
know if others were experiencing the same thing before I did.

Thanks!

Rob

--
Rob Frohne, Ph.D. P.E.
E. F. Cross School of Engineering
Walla Walla University
100 SW 4th Street
College Place, WA 99362
(509) 527-2075

That does make perfect sense. Thank you for the clarification.

Don

Paul, have a look at post 957 for more info on this issue.

thank you for that info, my old eyes aren't up to the task, so I'll live with it I guess