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the calibration is fine,it works with the is it sharp vna fine just not the saver one

Hi Eric and Ady
There is also the lazy way if you know what type of cable you have between equipment and the antenna
Use a time domain method to find the cable length (You need to know the cable VF) and then measure with the NanoVNA from the equipment into the cable save as s1p and import to ZPlot. The transpose the length of cable towards antenna and remember to select the cable type and you see the antenna impedance compensated for loss in the cable.
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af erik@...
Sendt: 6. december 2019 17:38
Til: [email protected]
Emne: Re: [nanovna-users] New version of NanoVNA-Saver: 0.2.1

I'm not an expert but this is what I understood:
Zplot is able to determine the impedance of the feed cable (if different from pure 50ohm) It also is able to calculate the frequency dependent loss This will help you understand what power goes into the cable and what into the antenna.
When you calibrate at the end of the feedline you ignore the cable.
When ignoring the cable (apart from the compensated delay) is ok, calibration at the end of the feedline is ok
--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

Hi pgc1683 (do you have a name or are you an alient ?)
I have repeated the measurement for sending you some s1p files. I have also made a report where the measurement are seen and exposed to ZPlot. Instead of implementing anything in the NanoVNA saver it is much simpler to save to s1p and import in ZPlot followed by a delay which is standard for ZPlot with selection of the cable types in question
For the VNWA software there is a simple interface to ZPlots where the measurement are automatic polled to the ZPlots
I respond to you questions below

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af pgc1682@...
Sendt: 6. december 2019 14:37
Til: [email protected]
Emne: Re: [nanovna-users] New version of NanoVNA-Saver: 0.2.1

Hi Kurt and others,

Sorry for wrong copied new post. I deleted it. Now the the correct reply:

Thanks for the detailed reply. You can send to me the measurements in file s1p format? You can measure this with professional grade VNA and export s1p format?

I frequently use zplots and sim smith chart ( ). Both program useful function extensions for vna-s. Many amateur grade instrument not have useful functions (Markers, cursors, graphs, etc.). I like nanovna-saver, many function available without external program. Some amateur grade commercials vna says: Laboratory grade. This is not true, i test the R&S entry level (!) handheld vna, much better.

Of course, many bad connector, adapters, cables exist. For example, my unkown (i think, Hugen, but not 100%) clone nanovna sma thru adapter very bad. Very lossy and not 50 ohm. I have another sma thru, much better. Near ideal with nanovna.
<<<Yes indeed the FF adaptor is very poor but from end November Alababa.com supply Hugen-H with low loss FF adaptor anf I have one it is very good
See my document for calibration data:
and female calibration NanoVNA-H.pdf


Professional adapters and calibration kit have low loss. I see many cheap adapter lossy. I think, this erros maybe compensatable. But easiest way change to good adapter.

I use lossy port extension trick on low frequncy (if osl calibration impossible), 1,8Mhz to 52 mhz. I not understand square wave signal how many bad. I think not good. Harmonics, for example.
<<< In principal terms the squarewave signal does not harm as mixed to an audio bandwith IF %KHz as I remember

Another questions, the calibrations. Nanova-saver see raw input values? Or selectable? I think not, use only 101 point nanovna calibration. This is bad for expert user, double calibrations. And 101*10 = 1010 point data, interpolate between 101 original calibration points not a best way. I think some ripple from this way, but i will test it. Professional instrument not recommended to use interpolated calibration point. If change frequency range, it works, but displayed the "uncalibrated" warning.
<<<< as all SOL standard has smooth running impedances traces 101 point are enough point and the interpolation is very close to exact calibration. NanoVNA does not use raw data but does small changes to the NanoVNA calibration. That is why you always must calibrate the NanoVNA with same setup of test cables and do a full calibration followed by a save to C0
Then start using NanoVNA saver and do calibration and measurements:

On nanovna, i can not find correct calibration. For example open short load delays not user definable. I have not zero lenght N osl calibration kit. Not all sma short has zero delay. I think requres firmware mod.

<<< the NanoVNA requires ideal calibration standard meaning open (precompensated with 50fF or 2.5ps one way) 0ps short and pure 50 ohm load. It does not matter whether this is SMA as the supplied kit or N, BNC or PL259 etc. But the trouble is such devices does not exist apart from N female short. But there is a simple stunt to do as when using N, BNC, PL259 flange adaptor the grind down the center conductor flush with the rear side for open. Solder a 2 mm Cu or Brass disk to the center conductor and the rear for short and for open use a single 49.9 ohm 1% SMD resistor as load (in the NanoVNA-saver you need anyway to create a calibration kit file and the define load as 49.9ohm) else use two 100 ohm 1% SMD resistor and in both cases grind down the center conductor to a 0.5mm height. Now you have to figure out the fringe C for the open and the shunt C for the load. More on that later but in the nanoVNA calibration kit file it is "forbidden" to use shunt C for load so the shunt C must be converted to a negative inductance after the formula L in pH= - C-shunt in fF*2.5. Then the delay from the rear of the bulkhead adaptor to the calibration plane has to be calculated and for that purpose a caliper is used.
measure in mm e.g. from the front of the female N down to the calibration plane subtracted from the entire length form front to rear and multiply by 4.79 and you have the one way delay = the offset used in NanoVNA. This way you have a super N kit. The fringe C for load is a bit dependent the amount of solder used but about 150fF and the open fringe C is 80fF
Calibrating the VNWA is just using the fabricated N standard and in the NanoVNA enable the negative electrical delay with the calculated adaptor delay. Then the calibration to the rear of the adaptors are pulled back to N adaptors calibration plane. If only the calibration of the NanoVNA prior to using the NanoVNA saver then forget about the Electrical delay as that only facilitate fairly correct measurement using the NanoVNA as standalone without compensating for the fringe C of open and load.
If you want to do it the complicated way see my document:
to fabricate a N Male and Female calibration kit rev2.pdf
Kind regards
Kurt

Thank you!? I will inspect my unit and if it's similar, I will order the LINK.
Bob
On Friday, December 6, 2019, 11:24:18 AM PST, Oristo <ormpoa@...> wrote:

> P2 is at the edge of the PCB and can only be used with the ST-Link dongle

For completeness? (from ):
nanoVNA <——–> ST-LINKV2
SWDIO <———-> ②SWDIO
SWCLK <———-> ④SWCLK
GND <—————> ⑥GND
NRST <————-> ①RST
VDD <—————> ⑧VDD 3.3V

A super big thank you to all involved for the manual.
Very special thanks to cho45 and Larry !!!

73, Hans
DJ7BA



Von: [email protected] <[email protected]> Im Auftrag von [email protected] Notification
Gesendet: Freitag, 6. Dezember 2019 16:16
An: [email protected]
Betreff: [nanovna-users] File updated in [email protected]



Hello,

This email message is a notification to let you know that the following files have been updated in the Files area of the [email protected] <mailto:[email protected]> group.

* /NanoVNA-User-Guide-English-reformat-Dec 6-19.pdf </g/nanovna-users/files/NanoVNA-User-Guide-English-reformat-Dec%206-19.pdf>

Uploaded By: Larry Rothman <nlroth@... <mailto:nlroth@...> >

Description:
This is a translated, reformatted and edited version of cho45's excellent NanoVNA User Guide. The document is 35 pages and is formatted for printing. Updated Dec 6-2019 - Added new section on Developer Extended Features, general updates.

Cheers,
The Groups.io Team

P2 is at the edge of the PCB and can only be used with the ST-Link dongle

For completeness (from ):
nanoVNA <——–> ST-LINKV2
SWDIO <———-> ②SWDIO
SWCLK <———-> ④SWCLK
GND <—————> ⑥GND
NRST <————-> ①RST
VDD <—————> ⑧VDD 3.3V

Larry, I will check to see if my board is like that.? If so, I can get the ST-LINK and have a fully working unit.? If not, no big deal.
Thanks for your efforts and patience; you have been a great help in my struggle.
Bob

Bob - P2 is at the edge of the PCB and can only be used with the ST-Link dongle.

Where is P2?? Which connections go where?? I have removed the USB socket and can't figure how to get it back.
Bob

Bob, have a look at this photo: /g/nanovna-users/photo/0/974?p=Created,,,20,2,960,0
You're connecting the ST-Link to P2 on the edge of the Nano's PCB.
You can pick up the ST-link devices from fleabay at about the same price.

Larry, I don't see how to attach the ST-link but for $2 it might be a solution.? Can you provide more info?
As for Aliexpress I have been having serious trouble with them.? The latest involves a mistake on the seller's part and my package was sent to the wrong place.? They are asking me to wait two months for resolution.? Not acceptable so I am going to avoid using them for future needs.
Bob

As yet I've had no issue with the current USB connector used... but its
small and fragile. On another piece of gear I've had issues with the mini
and micro USB connectors and finally removed it with care and replaced
it using a USB-B connector which while larger is robust and the
interconnect wires were short #30 wire wrap wires.

It is my plan for this unit once I make a suitable case to make that
change proactively. USB being a 4 wire plus ground its a trivial
change other than small (something I am used to). I tend to make
mods based on making it more robust in use.

-----------------
I do not accept private email due to forum scraping groups.io

Fixed the url

Bob,
Buy an ST-LINK adapter for a few bucks from this place where I got mine and you can read and write to the micro using the edge pins.
Works great.
...Larry

I like the idea of soldering a cable to the board.? When my mind is sufficiently clear I will take a look and see if I can identify the appropriate places on the board.
I am not optimistic because the connector I removed had many pins, and I don't have a proper guide to where to make connections.? Further, when I tried at one point to apply 5V here or there I got no results.
What I have now works well and I am loath to repair it.? It's basically a cable coming from the nano and has a USB plug on the end.? The main things that could be improved would be to add the data lines and to have a socket on the nano.? The latter isn't going to happen.? So basically I just want to know where to connect the other two wires so I can transfer data.
It's not clear on the board, what goes where and I would be unhappy if I messed it up worse than it is.
If I need to transfer data I have the fully working unit I can use.? Most of the time I am content with local operation so it's not that important.? I get very accurate readings and don't want to monkey with the bit of success I have.

There are two losses reported when measuring S21. One is reflection loss (mismatch) and the other is losses in the conductors (I squared times R ) and dielectric. If the transmission line is coax between CH0 and CH1, a common mode choke does is invisible.

Thank you Erik for quick answer.
Actually I wanted at first to know the antenna impedance, but having also
info about the feeder seems very interesting.
Thank you also Rune for the very useful software NanoVNA-saver, it's a full
job hobby just to play with all the features.

I'm not an expert but this is what I understood:
Zplot is able to determine the impedance of the feed cable (if different from pure 50ohm)
It also is able to calculate the frequency dependent loss
This will help you understand what power goes into the cable and what into the antenna.
When you calibrate at the end of the feedline you ignore the cable.
When ignoring the cable (apart from the compensated delay) is ok, calibration at the end of the feedline is ok
--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

Dear Erik,

regarding your method:
"Using nanoVNA saver you can measure your antenna feedline with the antenna
disconnected and replaced with a OPEN/SHORT
The resulting two touchstone files can be imported into ZPlot and ZPlot
will calculate a full transmission line model (k0,k1,k2) for your antenna
feed cable including the delay.
Then you measure your antenna connected to the feedline and import in ZPlot
using the calculated transmission line model and have all the details of
your antenna without the impact of the cable or you use the calculated
delay in nanoVNA saver to quickly eliminate the biggest impact of the
feedline "

If I calibrate the feedline with O, S,L and then connect the antenna and
measure it with NanoVNA, what would be the difference comparing to your
suggested method?

TNX, 73 Ady YO2NAA

Dear pgc1682

The nanoVNA is a wonderful example of how to do the best with the least at a price point everyone can afford.
Has this lead to compromise? Yes. example is the size of the screen or the max 101 points. Many complain, but still like the low price.
How about the harmonics? As long as you measure non frequency translating devices the harmonics don't care, they are actually exploited in a very clever way.
How about the quality? Can you compare to a professional VNA 100 times more expensive? No, but it is still extremely useful.
Can you overcome many of the limitations. Yes, people (like Rune) are creating excellent PC SW to augment the nanoVNA functionality (like more points, better calibration, more measurements)
Problem with this SW is that it has to strike a balance between what is possible versus what makes sense.
Should the SW try to copy what the high end VNA's do or focus on the broadest possible user base in a way that it is easy to understand.
All difficult choices and we use the group to exchange views and collaborate.
Often new people (like you) appear on the forum that are puzzled about what the nanoVNA can/should/cannot do.
Posting questions will likely get answers and we also accept people can get a bit frustrated.
Never assume people are doing stupid things, they may just be different from what you would do and that is OK.
--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK