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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

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] group.

• /NanoVNA-User-Guide-English-reformat-Dec 6-19.pdf

Uploaded By: Larry Rothman <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

Paul,
It sounds as if you did not calibrate the Nano correctly and the PC app is getting corrupted data.
Please follow the various calibration instructions either on the forum Wiki or in the User Guide (Files section) and try again.
Thanks,Larry

Rune, thanks for the reply, much appreciated.

I download the '64' version of VC++ 2015 first and that didn't work...8^)

Then did the same for the '86; version and Eureka!..

There it is, a window full with a nice large Smith Chart.

Now to figure out how to use it when my Nanovna-H arrives around the end of December. I'll be doing some reading in the mean time.

Thanks for the assist.

--
Chuck, W5USJ

I get a similar problem,for the first few mins the screen jitters all over the place,then settles down but i have no cursor on the polar or smith chart,its pretty much unusable as it is for me.

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.

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.

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.

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.

On 04/12/2019 14:22, matyslubin@... wrote:

Barry, looks like you are from UK.
I'm planning to buy one of NanoVNAs. Where did you buy your device, eBay ? Which firmware did you use for it?
I will be using my NanoVNA for the same purpose as you, to calibrate my antenna at 1090 MHz. So, ideally will be nice to have 1500MHz range. Thanks in advance for support.

My unit came from an eBay supplier in Basildon Essex, however the listing is no longer there.

I would suggest the nanovna-h which comes with case and all accessories including a USB-C to USB-C lead for use with phones that have USB-C.
This version includes resistors to allow the use of this cable.

Search ebay for nanovna-h and look for the supplier in Basildon.

I think it will come with the 1500MHz firmware (a friend of mine bought one recently and it did). If not it is simple to upgrade it.

For best results be sure to calibrate it over a fairly small range, say 1050 to 1150MHz before using it at 1090, or the 101 calibration points will be too widely spaced.

Nanovna-saver:
Save the calibration to a memory and also to memory 0 before using nanovna-saver.
You can then re-calibrate in the software over maybe 1000 points within the span of use, to get even higher resolution.

Have fun, hope it works out.

Barry

Gwen,

Thank you for this interesting solution, think I will leave this Chromebook stock (Version 76.0.3809.136 (Official Build) (64-bit) as there are several laptops and desktops also in us here, the Chromebook tends to be used for casual browsing and email.

73, Bob GM4CID

Have you had any other versions of NanoVNA-Saver running previously?

Do you know if you have a new-ish version of the Microsoft VC++
Redistributable library installed? (I think it should be included with SP1,
but I'm not certain)

--
Rune / 5Q5R

I may just do that thing, me. Got a couple of NanoVNAs sitting here. I just hadn't gotten around to trying the web client yet with it. But that can be done.

73,
Gwen, NG3P

No problem.
We all get ahead when we 'play' with our 'toys'? ;-)


On Fri, 6 Dec 2019 at 5:44 AM, Gyula Molnar<gyula.ha3hz@...> wrote: Hi Larry,
I'm glad that many people have noticed what the original author wrote in the "Know issues" section of the NanoVNA alpha1 kit assembly manual.
I think the same way, thank you for trying to confirm that I'm not trying in vain.

73, Gyula

Hi Larry,
I'm glad that many people have noticed what the original author wrote in the "Know issues" section of the NanoVNA alpha1 kit assembly manual.
I think the same way, thank you for trying to confirm that I'm not trying in vain.

73, Gyula

Downloaded the file and moved it to a different folder.
Apps nanovna-saver-v0.2.1.exe
Clicked on the file to run it. A window opened, a flashing cursor appeared briefly then the dialog box shown in the attached picture opened.

Environment:
HP EliteBook Folio 9470m running Windows 7 Professional SP-1

Any clues, ideas, etc...
--
Chuck, W5USJ

When I received my first nano a white gecko clone, the first thing I did was drop it with the dinky microusb cable plugged in. The entire usb connector pulled off and was basically destroyed.. So I did a cludgey fix. I took a scrap piece of PC board and made four islands on it using a Harbor Freight 3/8" spot welder cutter bit.(#63657). Th hen cut one end off an old type A USB cable.and attached one end to the scrap PC board and soldered the leads to the pads. Then I used a small gauge enameled wire and attached to the traces remaining from the old micrusb connector traces. This is the hard part. I cheated on the ground wire and attached it nearby as shown. After I was satisfied I covered the fragile connections in epoxy. The enameled wires are terminated on the other end on the appropriate pad. Its ugly but really pretty usable. Could be improved in a hundred ways. If you wanted you could probably fashion this into a PC board case. Your board could be different so double check where everything goes. I am just throwing out the general idea of how it might be done.

For everyone that wants to do complex transmission line analysis and has access to a sufficiently new MSOffice suite I suggest they use ZPlot, a free tool written in Excel
It can be downloaded from here

The excel file contains the calculation models for complex transmission line measurement calculation and compensation using a k0,k1,k2 model.
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
--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

Hi Paul,
I did ask you to clarify what the problem was, and what environment you're
running it on. Your description of the problem is in no way clear
enough for me to be able to answer it as it stands.

--
Rune / 5Q5R

is no one going to answer my question then?

Hi,
Starting from the end of November 2019, we(NanoVNA-F team) no longer produce RF Demo Kits with WWW.S*T.COM mark.