NanoVNA Custom Software

[joeqsmith]

I've been playing around with the new 1.0 software that I plan to release shortly.  While searching the forums for some decent firmware that supports the original hardware,  I kept coming across posts where people have damaged their Nanos.   One person had bought 5 of them and 3 were damaged.   This video gives some of my thoughts on how to protect the front end.   It also shows off the new software.   



I finally received some much needed feedback on the manual and need to address that.  I am also seeing a small problem with the software or maybe it's firmware, that needs to be corrected.  Things are starting to come together.   

[DrNefario]

I have been using my Original NanoVNA since December 2019 now and have gone through several FW loads.  I am now on edy555's v 0.8.0 and am quite happy with it and mostly use it on the bench with NanoVNA-Saver.  This is the latest FW version from edy555 and I don't know about others, but here are the features it has:

[joeqsmith]

Any known problems with it?   

[DrNefario]

In general I have not had any problems.  The github is at  https://github.com/ttrftech/NanoVNA and there is an issues list but some things seem more like a 'wish list'.
I have taken lots of data with the Nanovna-saver program including downloading S parameters and saving the cal sets.
I downloaded the binary that is listed as the latest: https://github.com/ttrftech/NanoVNA/releases/tag/0.8.0
Also, I am not a software type, but I did compile the master as listed and it did work OK, but not with the saver program.
The saver program gave me this error list when I tried to run it with my compilation:  ( it seems to not have a valid version )

Traceback (most recent call last):
  File "NanoVNASaver\NanoVNASaver.py", line 516, in serialButtonClick
  File "NanoVNASaver\NanoVNASaver.py", line 538, in connect_device
  File "NanoVNASaver\Hardware\Hardware.py", line 111, in get_VNA
  File "NanoVNASaver\Hardware\NanoVNA.py", line 40, in __init__
  File "NanoVNASaver\Hardware\VNA.py", line 61, in __init__
  File "NanoVNASaver\Hardware\VNA.py", line 186, in readVersion
IndexError: list index out of range

So, I went back to the binary v 0.8.0 which does not give any errors.

[joeqsmith]

Thanks for the input.  Not being able to rebuild it doesn't give me a lot of confidence but I went ahead and downloaded the image you suggested.   The first thing I notice is they did not adopt the 10KHz feature.   More useful for me than a battery indicator but oh well.   It looks like they went the other way and allow it to operate a bit over 2.1GHz.   It was pretty poor above 300MHz.  I played with the hardware above a GHz and even used it in that last review I made for the V2+4. 

Its running the regression test.

*****
What do you use the NanoVNA for?   What frequency ranges do you use?

I may have you try and run a test for me in the near future. 

[DrNefario]

I use it for various things including sweeping filters, measuring and designing impedance matching networks, component measuring and some antenna matching.  I would like to build the crystal test fixture for occasional use.  Most of this has been below 300 MHz, but I have used it for some stuff up to 1 GHz.  I have an HP3577 and an HP8753C but it is so convenient to grab the Nano and get the data into my PC that I have been mostly using the Nano.  I plan to buy one of the newer designs that would cover 4 - 6 GHz but am waiting for the designs and the shipping situation to gel.
I rarely use the built in display and would be just fine with a headless unit.  I notice that the NanoVNA-Saver application just freezes the display on the Nano, which is OK but I wonder if there would be anything to gain by blanking it when using it headless.  I realize that would require different firmware for the Nano, but this mode might be something to consider adding for the folks that are designing these new VNA's. 
I would be happy to run a test for you.  deflatermaus at outlook dot com.

[joeqsmith]

The 8753C is a workhorse.   There may be better software for your PC that supports it.    Your 3577 seems like it would be the unit of choice for the amateur and CB radio group.    Have you ran into cases where the 3577 provides any use to you compared with the original Nano? 

I have created a new repository on Github for the old hardware and have uploaded test reports for the two versions of firmware.  One is the last version that member RadioListener posted that I had rebuilt, the other the TTRFTech binary you linked. 

When you run the TTRFTech firmware, does the software you use have any sort of metrics that it provides?   Have you noticed any differences in the performance when running it with the PC?   

[joeqsmith]

It seems like the new firmware may have a smaller message buffer or is just using up more CPU time showing the low battery indicator.   I stack commands (send more than one) and parse the responses in a separate thread to speed things up.  This seems to cause the new firmware problems and it chokes.   You can see the effects in the two reports.   It's funny with it being as slow as it is that it has any problems.   

With the firmware still being developed, supporting it seems like a problem.  Looking at the software repository is seems the original author is no longer listed as a developer.   Looks like 15 people  working on it now.   Would enjoy hearing from Rune B. Broberg on why he stopped working on it. 

Marvellous... Thank you.

Peter

To make the software somewhat usable for you, I would cripple my software to work with the new firmware.  This will allow you to continue to play with the latest releases of firmware up to the point where they brake it.  At that time you would just need to archive the firmware that works the best for you.   

From a software point of view, the main difference between the old and new VNAs is how the new VNA will just send the raw data and it's fairly fast.  The old required you to request both channels seperatly.   If you are only looking at S11, there's no reason to ask for the second channel.   I would leverage this to get faster updates.  Still very slow but hey, it's $50.   When using S21, I always collect both channels which doubles the time it takes to update the screen.  The advantage is the software behaves more like the V2+.    For measuring crystals, I don't see it being a problem.    If you plan to try an use it for other measurements, you may run into snags. 

[DrNefario]

Several months ago, my 3577 POST indicated an over current event by the LED's status.  There was nothing on the screen.  I traced it down to a problem with the display module and when this module is unplugged it appears to boot OK as for as the front panel indicators tell me.  I am debating weather to buy the LCD display replacement or sell as is.  So, unfortunately I can't do any comparisons with this.  I am slowly moving into a condo and really don't have room for it.
I see that you have been to:
https://github.com/NanoVNA-Saver/nanovna-saver.  I have been following the forums on groups.io for the Nano and wiki at https://groups.io/g/nanovna-users/wiki/12336.
I guess Rune thought it was useful as is and left it for posterity at github.  I'm think if you posted there he would reply as he has been quite active on the forum.

I really have not compared the stand alone performance of the Nano to it working with the Saver program, but from what I read in the forums I trust most of what it tells me. 
I'll look at your reports later to see what you found.  Thank you for your work and informative videos!

[purpose]

To make the software somewhat usable for you, I would cripple my software to work with the new firmware.  This will allow you to continue to play with the latest releases of firmware up to the point where they brake it.  At that time you would just need to archive the firmware that works the best for you.   

From a software point of view, the main difference between the old and new VNAs is how the new VNA will just send the raw data and it's fairly fast.  The old required you to request both channels seperatly.   If you are only looking at S11, there's no reason to ask for the second channel.   I would leverage this to get faster updates.  Still very slow but hey, it's $50.   When using S21, I always collect both channels which doubles the time it takes to update the screen.  The advantage is the software behaves more like the V2+.    For measuring crystals, I don't see it being a problem.    If you plan to try an use it for other measurements, you may run into snags.

Mr. Smith,
Updating, or down dating the firmware takes seconds, so should you release your software I would still be game.
On another note... I've just ordered a NanoVNA H4 (bigger screen version),  because apparently there is a firmware available that gives you 401 data points. We can't have angular Smith charts.



Peter

[Kean]

Updating, or down dating the firmware takes seconds, so should you release your software I would still be game.

Peter, If you haven't already, you can check out the version he released in late January - but as Joe mentions above it is intended for the V2 Plus
https://github.com/joeqsmith/NanoVNA_V2Plus/releases/

[joeqsmith]

The V2+4 supports 401 data points running standalone and 1024 when using the PC (which is really all I care about).   It can download it at 400 data points per second.  That's everything.   When I demonstrated how to sweep in small segments, it was to overcome problems when looking at narrow band parts for SPICE.  The V2+ removes the need for it but I still have it included in the software.   

Yes, I checked out their Github account today to see if I could learn anything.   I was surprised the original developer not being listed.  With 15 developers, I expect that software is very polished by now.   They adopted segmented sweeps early on and I would have expected them to roll in any other features I had shown they felt would be useful.  From reading the groups,  I didn't see a lot of people actually experimenting with RF.    So spending resources adding support for mixers, transfer relays, automated crystal characterizing may not make a lot of sense if only a few people are asking for it.   That's really IMO what people should be doing as they have a much larger support group.   

I just finished editing the manual after getting some very good feedback on it and I still plan to release the software.   Running that regression test gives me some idea what needs to be done but it will require a lot more testing.    I changed my software to ease up on demands from the firmware.  It's slow but at least the data rates are stable now.     

[purpose]

Peter, If you haven't already, you can check out the version he released in late January - but as Joe mentions above it is intended for the V2 Plus
https://github.com/joeqsmith/NanoVNA_V2Plus/releases/

Have checked it already, Mr. Kean.

Thanks
Peter

[purpose]

The V2+4 supports 401 data points running standalone and 1024 when using the PC (which is really all I care about).   It can download it at 400 data points per second.  That's everything.   When I demonstrated how to sweep in small segments, it was to overcome problems when looking at narrow band parts for SPICE.  The V2+ removes the need for it but I still have it included in the software.   
 
Ace.

Yes, I checked out their Github account today to see if I could learn anything.   I was surprised the original developer not being listed.

Dislord is credited in the firmware I currently run. I tried his 1.0.38 in the hope of maybe upping the data point count, but it's limited to the H4 version.

 With 15 developers, I expect that software is very polished by now.   They adopted segmented sweeps early on and I would have expected them to roll in any other features I had shown they felt would be useful.  From reading the groups,  I didn't see a lot of people actually experimenting with RF.    So spending resources adding support for mixers, transfer relays, automated crystal characterizing may not make a lot of sense if only a few people are asking for it.   That's really IMO what people should be doing as they have a much larger support group.
 
If only they could be more like you, cough.

I just finished editing the manual after getting some very good feedback on it and I still plan to release the software.

Marvellous.   

Running that regression test gives me some idea what needs to be done but it will require a lot more testing.

When you're good and ready, sir. 

I changed my software to ease up on demands from the firmware.  It's slow but at least the data rates are stable now.
 
I doubt you not.   

Many thanks
Peter

[joeqsmith]

I tried out the basic functions and checked my test loads using the new firmware.  Seems alright.   Looking in my pile of junk crystals, I had a 10MHz NYMPH that I thought I could run to give you some sort of a reference what you should see.   

Beyond suggesting you not waste too much time with the EXE, my only other advice is read the manual.    Good luck.     

[purpose]

The old RTFM, eh?
Well, it'll have to wait for the morning.

Many thanks, Mr. Smith.

[joeqsmith]

Not really.  When I see read the fucking manual, I normally end the conversation which is not my intent.   That manual is there for a reason.  Make good use of it.   If you have questions not covered by the manual, let me know and I can add more detail.  That way others benefit.  Now that the manual has been updated, I doubt I will make a clip showing how to measure crystals. 

[purpose]

Morning Mr. Smith,
Well I did read the manual... well the crystal pertinent bits, just so I could give it a try before I went to bed.
Fired straight in and am currently characterising away. I also forgot to go to bed.
I'll certainly delve deeper into your writings and give any feedback I note.
Very interesting to see the very different responses of these Chinese made jobbies. No wonder they're dirt cheap.
When they're all done, I can't wait to press sort.



Once again
Very many thanks
Peter

[joeqsmith]

If the goal is only to press sort and see what comes up, just select save 10-50 times for the same crystal and try it.   If the goal is to actually measure crystals, the plot you show doesn't look right.  You can waste a lot of time taking bad data.   I suggest your time is better spent making sure things are correct before going further.   

First thing are those spikes in the frequency.  There is no way the crystal should shift frequency like that.  It wouldn't recover that fast.  Something else is going on, maybe noise.  Assuming the cables are tight and you're not touching anything, maybe it's your Nano.  Some versions of firmware would show bad readings at random.  That's part of the reason for the regression testing.  I haven't seen this problem for some time.   It should be obvious that running the same firmware removes a lot of questions and may save you a lot of time.   

Start by selecting the Xmsn Rectangular from the Main menu.   With your short installed in place of the crystal,  it should read well within 0.1dB after proper calibration (Capture1.PNG).  Make sure you understand the difference between the Nano's internal calibration and the software's.  Post a screen shot.

Assuming that the gain and noise look good, I would select Record and let it run for 10 minutes or more.   Press Record again to turn off the recording.  Select Advanced, Surface, Add Waveform and then load the file you saved the data to.   Next select Narrow Band Zoom and select S21 Mag.   You should have << 0.1dB noise P-P.   Notice mine after touching the setup takes a dive but is still within 0.045dB P-P (Capture2.PNG).  Post a screen shot.

Assuming you are not seeing a problem up to this point, select the Main menu (you should still be seeing << 0.1dB) and swap out the short for one of your 10MHz crystals.  You should see a VERY smooth curve (Capture3.PNG).    The peak is the Attenuation.  You show 20dB which seems very low.   Post a screen shot.

Select Record and save the data to a new file.  Let it run for another 10 minutes or more.   Don't touch anything and stay away from the fixture.  If you have a lot of air flow in the room, my standard practice it the beach towel.   It's too bad that the Nano doesn't have an ambient temperature sensor.  People would rather have a worthless battery indicator.   I would make a note of the temperature if you plan to try and reproduce the test or are collecting the data over long periods of time.   100ppm/degC with even a 2 degree shift and a 10MHz is easily detected. 

Select Record again to stop the recording.  Select Surface and select Flush.  Now select Add Waveform.  Looking at both S21 Mag/Phase, it better be very clean.  (Capture4 & 5)

If all of that seems good, I have no idea what those spikes are.  If a second crystals shows the same problem and you are running identical firmware, it seems there is a problem with the Nano, cables, not tightening things, external noise source....  You need to figure it out before wasting time measuring parts.

If you find the problem and get similar data, I would next validate that the C0 measurement is working.  If you don't have a good RLC meter,  I suggest installing a known capacitor.  Maybe a few values from 10pF to 100pF.   Depending what you have for parts, their tolerances can be pretty wide.  Just make sure that the numbers are in the ballpark and you should be fine.  If you insert a 100pF capacitor and it reads 50pF, something is obviously wrong.  Try another capacitor.  This shouldn't be a problem based on the data you posted for your jig.  Again, that assumes you have properly calibrated the setup. 

***
Very poor grammar for even me.     

[purpose]

Evening Mr. Smith,
If the goal is only to press sort and see what comes up, just select save 10-50 times for the same crystal and try it.
OK. Sometimes I act like a schoolboy.
You can waste a lot of time taking bad data.
A good job I actually went to bed.
Start by selecting the Xmsn Rectangular from the Main menu.   With your short installed in place of the crystal,  it should read well within 0.1dB after proper calibration (Capture1.PNG).  Make sure you understand the difference between the Nano's internal calibration and the software's.  Post a screen shot.

Next select Narrow Band Zoom and select S21 Mag.   You should have << 0.1dB noise P-P.   Notice mine after touching the setup takes a dive but is still within 0.045dB P-P (Capture2.PNG).  Post a screen shot.

Quite possibly not narrow band zoom.
Assuming you are not seeing a problem up to this point, select the Main menu (you should still be seeing << 0.1dB) and swap out the short for one of your 10MHz crystals.  You should see a VERY smooth curve (Capture3.PNG).    The peak is the Attenuation.  You show 20dB which seems very low.   Post a screen shot.

I would make a note of the temperature
23 new degrees.



If all of that seems good, I have no idea what those spikes are.
Probably operator error. I'm really not that bright.

Many thanks
Peter

[purpose]

A few spikelets and a hump when I went to get some water.

[joeqsmith]

Start by selecting the Xmsn Rectangular from the Main menu.   With your short installed in place of the crystal,  it should read well within 0.1dB after proper calibration (Capture1.PNG).  Make sure you understand the difference between the Nano's internal calibration and the software's.  Post a screen shot.

Notice how you have ran a complete calibration where in every graph I show the data is normalized.   Do yourself a favor, stop randomly pressing buttons,  go to page 71 and carefully read section 14.4.  It looks like this may have been the cause of that -19dB you first showed as you are now at -3.6dB.   I am guessing that is still not right.   I am not even sure how you would use that full calibration with the fixture.   Maybe you felt you should run a full SOLT then installed the fixture.  No matter.  It you want to get it working, you must follow the directions in the manual.  If something is not clear, let me know so I can address it.       
 
Notice in the data I have presented, the span is set to 500Hz.   You have clearly not selected zoom and are looking at a very wide frequency range.   In the manual where it says Select Zoom, you have to actually select Zoom.   You can't just skip steps.        

Once you have it correctly calibrated and the span set, then run your 10 minute collection.  There is no reason to collect 10 minutes of bad data.   Your setup should be the same as what I show or something is wrong.   Once you have that, don't go any further.  Just post a screen shot of the 3D plot.   I suspect with such a wide span, you may not see the noise problem.

[purpose]

Do yourself a favor, stop randomly pressing buttons
I identify as a toddler... it's my job.
Still, I'm glad my first joeqsmith admonishment was a wrist slap. instead of a punch in the mouth.
I'm going to have to have the night off and read the manual a few times, because following instructions and replicating your charts
are beyond me right now.
This is the latest...

[joeqsmith]

Good Job.  This is what I was expecting.   Now what is causing those spikes?   Are you using the exact same firmware downloaded from the image mentioned in the earlier posts?  If not, I would start there.   Again,  I had seen something like this with the earlier versions of firmware.   

If you are running the same firmware, you could try to move the cables and your jig to see if it has an effect but assuming you are not anywhere near it while it it running, I doubt this is the problem.   If it's not the firmware, I would guess the Nano itself.   You need to get this resolved before moving to the next step.

[purpose]

Just put in the edy555 firm 0.8.0.
Waveform update seems about half as quick.