Date   

Re: No Smith chart on the PC screen

Leif M
 

Aha. That's what are for. It works now, Thank you.


Re: Better, Worse, Worst....... baloney.

Warren Allgyer
 

Today I received my third Nanovna. This one, I believe, is one of the "better" quality, completing the triad of better, worse, worst. The construction is noticeably higher quality with full, soldered shields on both ports. It came packaged neatly in a plastic box but with no battery. The front and back covers are painted fiber board, the same as the "worst" white salamander and not like the aluminum covers on the "worse" black model.

After calibration at 50, 450, and 720 MHz one significant performance difference was noted. The noise floor in the S11 Logmag display was noticeably quieter at -64 dBc. It was perhaps 5 dB p-p as compared with about 15 dB p-p for the "Worse" and "Worst" models.

However, when testing it at normal measurement levels there was no significant difference in the measurements at any of the three frequencies among all three. A summary of test results for the three Nanovnas, an AAI VIA, and my Rigol SA/RFbridge combo is attached.

For my purposes the three different versions are substantially identical and I would not hesitate to use and recommend any of the three.

Warren Allgyer
WA8TOD


Re: No Smith chart on the PC screen

Harald
 

Hi,
check for the "Smith.png" and "Admittance.png" file.
They should be in the same direcory as the "NanoVNA.exe" File.
73 Harald
OE3HBS


No Smith chart on the PC screen

Leif M
 

The NanoVna seems to work but when I look at results on the PC screen I can't see the Smith chart. I see results plotted on the screen, probably on the Smith chart but Smith chart itself is not visible.
This is a Windoews 7 32 machine with a ordinary 27" inch screen. PC software gives this info(probably about the device): Kernel 4.00 Build time 2. Aug 2019.


Re: A bit off topic, but Nano VNA related.

Andy G0FTD <punkbiscuit@...>
 

Ok Larry, its a starting point that I never knew about.

I've not investigated anything to
do with the terminal stuff yet.

73 de Andy


Re: nanoVNA Real Resistance Measurement Range

Tom VA7TA
 

Greetings Mr. QRP,

Thanks for the analysis! Gosh it is amazing how close my DIY 50 Ohm BNC load with adapter combination match the SMA 50 Ohm reference load that came with my nanoVNA! I don't know how good the supplied reference is in terms of return loss but at least it is comforting to find that the two loads match closely. Part of the reason for the good match may be because the SMA F-F adapter used to connect the supplied SMA load is roughly the same length as the BNC-SMA F-F adapter. Your VSWR plot shows that the VSWR buckets out around 200 MHz. Maybe by pure coincidence my SMA-BNC F-F adapter happens to add a tiny amount of series inductance that cancels some of the 0.5pF shunt capacitance exhibited by my DIY BNC load.
--
Enjoy!
Tom
VA7TA


Re: A bit off topic, but Nano VNA related.

James R. Chastain
 

Interesting!!

On Thursday, September 19, 2019, 10:29:12 AM EDT, Andy G0FTD via Groups.Io <punkbiscuit=googlemail.com@groups.io> wrote:

I just checked my NanaoVNA output and frequency accuracy, utterly superb.

Good enough to generate WSPR signals, or simple FSK/CW QRSS signals.

The latter are normally send with a 5Hz shift, with a dot length of 6 seconds.

Is there a simple way to use the VNA to generate such signals via USB ?

73 de Andy


Re: NanoVNA LNA S21 & S11

QRP RX
 

On Thu, Sep 19, 2019 at 03:17 PM, hwalker wrote:


and a 6 dB attenuator to CH0
6 dB is too small, the output level may be very high for LNA and may overload it, so you may get incorrect measurement. I'm using 30-60 dB attenuator on the LNA input for measurement.


Re: DIY loads

James R. Chastain
 

Thanks. Just what I wanted.

On Wednesday, September 18, 2019, 10:41:26 PM EDT, w0lwa <trberger@colby.edu> wrote:

Rod

Have a look at
https://www.qsl.net/in3otd/electronics/VNA_calkit/SMA_female.html
and start reading on page 24 of
http://n2pk.com/VNA/n2pk_vna_pt_2_ver_b2.pdf



On 9/18/19 9:35 PM, James R. Chastain via Groups.Io wrote:
Any problems making your own calibration loads? 50 ohm non inductive resistor and a shorted connector or am I missing something?
KD0XX (Rod)



--
=============================================
Thomas R. Berger      Emeritus Professor
53 Kendal Drive      Mathematics Department
Oberlin, OH 44074    Colby College
K1TRB                Waterville, ME 04901
=============================================


Re: NanoVNA Saver - bug report?

Rune Broberg
 

Hi Nick,
please try putting the full path to the file in the field, not just the
file name. It may be a matter of which folder the software sees as its
working folder (generally controlled by your OS).

I liked the firmware message as well, but I haven't found a nice place to
put it, and several people were having problems running out of screen real
estate - so for now, it's no longer shown. I'd love to have it back, though.

--
Rune / 5Q5R

On Thu, 19 Sep 2019 at 21:03, Nick <g3vnc@uk6.net> wrote:

Hi Rune

thank you so much for this application which I have been using to good
effect this past week with the nanoVNA.

I think there may be a problem with saving and loading calibrations.

Yesterday I did a calibration which I called full_sweep. The full_sweep
file was saved to the nanovna-saver directory, and I could shutdown
nanovna-saver, restart it, and load the calibration.

Today it will not load. I get this

2019-09-19 19:49:53,703 - NanoVNASaver.Calibration - ERROR - Failed
loading calibration data: [Errno 2] No such file or directory: 'full_sweep'
Traceback (most recent call last):
File "/home/nick/nanovna-saver/NanoVNASaver/Calibration.py", line
430, in loadCalibration
file = open(filename, "r")
FileNotFoundError: [Errno 2] No such file or directory: 'full_sweep'

The file is still present. Is this a problem with directory paths?

73
Nick
G3VNC

PS: I used to like the build date message from the firmware when you
first connected to the device!

On 18/09/2019 21:36, Rune Broberg wrote:
I just released 0.0.10:
https://github.com/mihtjel/nanovna-saver/releases/tag/v0.0.10




Re: Firmware summary

Larry Rothman
 

I agree and was going to put forth the same request as Rudi just did:

On Thu, Sep 19, 2019 at 02:39 PM, <reuterr@web.de> wrote:

Hello Erik,
Thank you for adding your extension to the Hugen nanoVNA version 0.1.1.

It would be nice to fill out in the "version window" the version number,
e.g.: 0.1.1 + scan, 1500MHz

Then you could look up what version is actual flashed.
Due to an ever-increasing number of NanoVNA firmware developers providing binaries on this forum (I think it's up to 5 now) and building different variations and/or experimental versions, I (and others) have a request to make of those same developers:

Please use the NanoVNA's boot-up central message field to provide at least the developer's forum name along with their version number (or date) and possibly included options.

All Nano F/W versions I download are archived and labeled with the developer name, date, F range and any other options along with any sub-version numbers if updates come out.
It could be automated through the make file for convenience.

How do the developers (you know who you are) feel about this?

73
Larry


Re: NanoVNA Saver - bug report?

Nick
 

Hi Rune

thank you so much for this application which I have been using to good effect this past week with the nanoVNA.

I think there may be a problem with saving and loading calibrations.

Yesterday I did a calibration which I called full_sweep. The full_sweep file was saved to the nanovna-saver directory, and I could shutdown nanovna-saver, restart it, and load the calibration.

Today it will not load. I get this

2019-09-19 19:49:53,703 - NanoVNASaver.Calibration - ERROR - Failed loading calibration data: [Errno 2] No such file or directory: 'full_sweep'
Traceback (most recent call last):
File "/home/nick/nanovna-saver/NanoVNASaver/Calibration.py", line 430, in loadCalibration
file = open(filename, "r")
FileNotFoundError: [Errno 2] No such file or directory: 'full_sweep'

The file is still present. Is this a problem with directory paths?

73
Nick
G3VNC

PS: I used to like the build date message from the firmware when you first connected to the device!

On 18/09/2019 21:36, Rune Broberg wrote:
I just released 0.0.10:
https://github.com/mihtjel/nanovna-saver/releases/tag/v0.0.10


Re: Firmware summary

reuterr@...
 

Hello Erik,
Thank you for adding your extension to the Hugen nanoVNA version 0.1.1.

It would be nice to fill out in the "version window" the version number,
e.g.: 0.1.1 + scan, 1500MHz

Then you could look up what version is actual flashed.

I am working mainly with MacOS.
In case you use the program "dfu-util" on Linux or MacOS for flashing, the USB vendor ID is 0000 in your .dfu file, and you cannot flash.
Error message: dfu-util: Error: File ID 0483:0000 does not match device (0483:df11 or 0483:df11)

In this case I have to transfer your .dfu file to Windows, use DfuFileMgr.exe to convert your file to .hex,
and convert it back to format .dfu with entering the USB vendor ID: DF11.
Then copy it back to MacOS and use dfu-util for flashing.

Therefore it would be also nice to add the USB vendor ID : DF11 to your .dfu file.

73, Rudi DL5FA


Re: nanoVNA Output Voltage

Warren Allgyer
 

Some clarification from my earlier measurement.

The Measurement output from CH0 ranges from -13 dBm at 55 kHz to -36 dBm at 900 MHz..... a more than 23 dB variance.

Beginning at the first increment above 300 MHz the Measurement output switches from fundamental to 3rd harmonic. So, for example, when measuring at 330 MHz the 330 MHz Measurement output being used will be at -19 dBm the there will also be a much higher power fundamental signal output at 110 MHz at -9 dBm. The Nanovna ignores this fundamental frequency by virtue of its heterodyne mixing but users should be aware of its presence when performing S21 measurements of preamps and the like. These relatively high power fundamental frequencies can easily overload amplifiers and distort measurement results.

Another example: The Measurement output at 900 MHz is way down at -36 dBm but the 300 MHz fundamental that is generating that measurement frequency is also present at a whopping -9 dBm, nearly 30 dB higher! User beware!

Warren Allgyer


Re: NanoVNA LNA S21 & S11

Said
 

Hi hwalker.Very thanks for answering my post & i read before your procedure. So the S11 isn't interesting in the LNA Performance.
Regards.


Re: nanoVNA Output Voltage

Erik Kaashoek
 

The output power of the SI5351 is automatic set depending the requested sweep frequency, 2mA below 300MHz, 8mA above 300MHz
Similar for a manually set fixed output frequency using the freq command

You can manually control the power through console by issuing

power [0-3]

The power is in small steps controlling the SI5351 current into the output attenuator
0->2mA
1->4mA
2->6mA
3->8mA

Issuing
power -1
sets the nanoVNA again in automatic power mode

If you report output power please indicate at which power setting the output is generated.


Re: nanoVNA Output Voltage

df2jp_1
 

Hi, Andy,

we had the same idea, I measured the output and the frequency accuracy on the weekend. It is very bad if there are 5 kHz difference, e.g. on LF...the band is < 2kHz wide.
I have set the measurement results under Photos, Output to frequency.

Measuring equipment Advantest R3131 with Rubidium-10MHz reference.

73 Joe


Re: A bit off topic, but Nano VNA related.

Larry Rothman
 

Why not try the following console commands through a script:

pause (the scanning - still generates output)

now loop the following via a data driven stream...
freq 1000000
(wait)
freq 1000005

I don't know how fast these commands can be sent - talk to Rune (nanovna-saver author)

73
Larry


A bit off topic, but Nano VNA related.

Andy G0FTD <punkbiscuit@...>
 

I just checked my NanaoVNA output and frequency accuracy, utterly superb.

Good enough to generate WSPR signals, or simple FSK/CW QRSS signals.

The latter are normally send with a 5Hz shift, with a dot length of 6 seconds.

Is there a simple way to use the VNA to generate such signals via USB ?

73 de Andy


Re: nanoVNA Output Voltage

Andy G0FTD <punkbiscuit@...>
 

I just measure 100mv peak into 50R at 50Khz to 50Mhz (-10dbm)
At 70Mhz it was 70mv (convenient to remember).
I was amazed at how accurate the out put frequency was according to my GPS calibrated freq counter too.

73 de Andy

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