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This might be interesting





SMD CHARACTERIZATION USING PROGRESSIVE DE-EMBEDDING METHODS
(AUTOMATIC FIXTURE REMOVAL) WITH A VNA

Copper Mountain Technologies (CMT) will present modern methods to measure SMD type components mounted on 1-port and 2-port fixtures. The proposed methods uses advanced algorithms to de-embed fixture effects. The session will compare traditional and modern ways of de-embedding fixture effects.


I don't think you have to be an IEEE member to sign up, they're just the sponsor - the member number is an optional field in the registration

On 7/6/21 4:49 AM, Lawrance A. Schneider wrote:

I would think that using a transformer to match impedence would introduce even more error: nano - transformer - antenna. That is a question and not a declaration.

Thanks, larry

Depends on what you call error.? If the transformer is part of the VNA (i.e. you do the cal at the DUT end of the transformer) any effects of the transformer are rolled into the calibration.

If the transformer is part of the DUT, well, it is what it is - you're measuring the combination of antenna and transformer as a system.

In either case the "error" (interpreted as deviations of calibrated result from those that could be made by a perfect instrument) will be related to the SNR for the measurements - and that won't be significantly different in either configuration.

Something that might be of interest is that the Surrey Amateur Radio Club, VE7SAR, < <>ve7sar.net > has a wonderful newsletter that comes out bi-monthly. The newsletter is usually around 110 pages. The last several issues have had articles titled, Measurements with the NanoVNA". The Nov - Dec 2020 article deals specifically with "Establishing the Characteristics of Unknown Toroids".

73,
Gary - W6GVS
Dowagiac, MI

I would think that using a transformer to match impedence would introduce even more error: nano - transformer - antenna. That is a question and not a declaration.

Thanks, larry

I use a Mini-Circuits FT-1.5-232+. They are a bit expensive.

Most TV antennas don't have that great a VSWR. Also common for TV antennas to uses a 75 to 300 ohm balun which makes things worse.

Attached is data on balun.

Here's the display from 10KHz to 610Mhz (I think) of a 75 ohm resistor after my DIY 50 ohm to 75 ohm matching pad.

Hi guys, The OP here. After watching the video on use of the 50 to 75 ohm adapters I decided I'd try to build one.
I think I did good... almost! As you may recall I'm working with TV antennas my channels are between 180MHz and 610MHz.
So I ran a scan,180MHz and 610MHz, of a 75 ohm resistor through my DIY 50 ohm to 75 ohm pad.The resistance varied from 50.1 ohm to 49.6 ohms.
and the reactance was as high as 168pH. I thought this was great. Then I decided to run the scan all the way to 900MHz. At about
675MHz the resistance goes down until at 900MHz it is 0.2 ohms.
Just posting for your feedback, to see what I did right or wrong.

(It was suggested that I post this on this forum by someone on the "F" forum)
Upgraded my "F" to sysjoint.com v0.15 (Apr 23, 2020). All went well. Here's the issue...and it may very possibly be pilot error (of course that's never happened before).
Markers: When I have only one selected I get the marker frequency displayed (separately not next to the marker legend though). The marker can be moved; the freq changes. If I have more than one marker selected I get no freq readout on the marker legends, that is, it doesn't show actual marker position. It shows for example: 7.000 when I'm looking across the 40M band...it does not change. What it DOES show on another line is a delta freq between the two markers (this is with "DELTA" selected or not).
Otherwise the upgrade seems fine. No freq readout next to the marker legend is pretty useless.
What may I be doing wrong or any other comments? Thanks!
PS. It was operating okay before upgrade (from v0.0.7)

Lou,
Since all of the technical information surrounding the nano-xxx series of devices and associated applications is created by hobbiests, there has been an effort by the group members, like myself, to help in creating various documentation.
The nanoVNA-APP was created by its author initially as a personal creation to assist in learning about their application. They shared the application with the forum members but its sourcecode remains private.
It was never documented and despite requests to the forum members for someone to create rudimentary docs for it - nothing was done.
So...... you need to play with it and read the various message threads (search for "nanovna-app").
The one item you need to know is only use version x.x.206 as the 207 version is buggy. Also, move the cursor to the graph area and right click to bring up a huge context menu where you can change a pile of parameters.
Finally, make sure you select to use the correct calibration source (device, none or app)
I hope this helps.
BTW - if you feel like it, why not create a doc while you're learning about the app.
Myself and others have already contributed a number of docs to the forum and it's time others started to as well......
regards
Larry

There is no official manual as the app started out as a hobby project for the author's personal use. A such there is no support. However you can search the message archive of this group and find a fair amount of information.

73

-Jim
NU0C

On Mon, 05 Jul 2021 07:27:42 -0700
"Lou W7HV via groups.io" <louandzip@...> wrote:

Good suggestions. Also worthwhile are "The Missing Manual" and "NanoVNA V2/ S-A-A-2 User Manual". I've read those and have used the V2Plus 4 some success as I already know a fair amount about RF and associated instrumentation. Here, however, my question is specifically on information regarding the nanoVNA-APP software for Windows. I know something of NanoVNA-QT and nanoVNA Saver but nothing on the nanoVNA-APP for Windows. That's what I'd like to find out more about.

Good suggestions. Also worthwhile are "The Missing Manual" and "NanoVNA V2/ S-A-A-2 User Manual". I've read those and have used the V2Plus 4 some success as I already know a fair amount about RF and associated instrumentation. Here, however, my question is specifically on information regarding the nanoVNA-APP software for Windows. I know something of NanoVNA-QT and nanoVNA Saver but nothing on the nanoVNA-APP for Windows. That's what I'd like to find out more about.

There is no "installation". Extract the contents of the .rar file to a folder of your choice. Create a shortcut for the executable in a place where you can find it and you are done.

73

-Jim
NU0C


On Mon, 05 Jul 2021 06:09:37 -0700
"Lou W7HV via groups.io" <louandzip@...> wrote:

On Sun, Jul 4, 2021 at 10:57 AM, Larry Rothman wrote:

/g/nanovna-users/message/22399?p=,,,20,0,0,0::Created,,nanovna-app,20,2,20,82946555?
Please remember that you need to un-rar the file.?

Thanks for the file link. That's the installation executable for windows? Is there a page or site that describes it or information that you can point me to?

Searching turns up too much and too little info at the same time. If you're new this nanoVNA phenomenon and not an all out nanoVNA enthusiast and aficionado, it's very difficult to follow and understand all the references and threads, especially as many are loose with nomenclature. A little help from an actual aficionado can go a long way in helping a neophyte get started.

Lou,
Download and read the "Absolute Beginner's Guide" in the forum's file section as well as Barry's slides:
/g/nanovna-users/message/22977?p=,,,20,0,0,0::Created,,posterid%3A1005447,20,2,0,83826635
Browse the forum Wiki sections as well - there is a lot of info to take in!
Best of all - play with your new device - build a jig and plug in coils and caps to see how they affect the Smith Chart, etc.

On Sun, Jul 4, 2021 at 10:57 AM, Larry Rothman wrote:

/g/nanovna-users/message/22399?p=,,,20,0,0,0::Created,,nanovna-app,20,2,20,82946555?
Please remember that you need to un-rar the file.?

Thanks for the file link. That's the installation executable for windows? Is there a page or site that describes it or information that you can point me to?

Searching turns up too much and too little info at the same time. If you're new this nanoVNA phenomenon and not an all out nanoVNA enthusiast and aficionado, it's very difficult to follow and understand all the references and threads, especially as many are loose with nomenclature. A little help from an actual aficionado can go a long way in helping a neophyte get started.

Thanks OneofEleven,
Error hasn't re-occurred ... I started using the -App because of the simple methodology to update Firmware ... and found it easy and straight forward to use ...
--
Cheers,
Ian
Melbourne, Australia

Don't forget the TinySA, you probably need one of those to. I paid somewhere around $50-$60 for mine. It's another great tool to have around.
Max KG4PID

The NANOVNAs are NOT spectrum analyzers. They are Vector Network Analizers.

You may want to look at the Tiny SA which IS a spectrum analyzer:



However, I have both and would recommend both for the capabilities of each.

Dave - W?LEV

On Sun, Jul 4, 2021 at 9:07 PM ADILSON MATOS <adilsonmatos2012@...>
wrote:

Richard Clemens!
Electroganetic Greetings

I've been wanting to buy a Spectrum Analyzer for a while, however, due to
the high price, I couldn't buy it. I recently discovered the Nano VNA
Analyzer that would be a low-cost outlet.

--
*Dave - W?LEV*
*Just Let Darwin Work*

Richard Clemens!
Electroganetic Greetings

I've been wanting to buy a Spectrum Analyzer for a while, however, due to the high price, I couldn't buy it. I recently discovered the Nano VNA Analyzer that would be a low-cost outlet.

Robin, truly excellent teaching!

Thanks for taking the time to illuminate.

John

at radio station VE7AOV

+++++


On 2021-06-28 1:46 p.m., G8DQX list wrote:

Peter,

it helps to think of the active devices, the PA power transistors, as
horribly non-linear devices. The base-emitter junction is a forward
biased diode, whose small-signal parameters vary over an RF cycle. The
collector-base junction is a reverse biased diode (think varicap diode

<>), whose capacitance (Ccb)
depends on the instantaneous value of the collector-base voltage. That
capacitance is then subject to the Miller effect
(
<>), and can provide
positive feedback from output to input.

Generally, the stage voltage gain is kept quite low to avoid any
danger of the apparatus becoming a power oscillator rather than a
power amplifier.

And since the base emitter junction is a diode, it obeys (more or
less) the diode equation for AC resistance, r'= .025/Ib?Ω, where Ib is
the base current. There is a lot more going on, for instance see

<>.

All that capacitance has an impact on the tuning of the input and
output networks. At this point, you might be thinking that any
functioning RF amplifier is a triumph of engineering ingenuity over
the Laws of Physics. You would not be far wrong.

73, Stay Safe,

Robin, G8DQX

PS: It was a good question, but with a complex answer, depending on
how much detail one can cope with!

...

--

You can find a lot of answers to your questions by searching the forums messages....
/g/nanovna-users/message/22399?p=,,,20,0,0,0::Created,,nanovna-app,20,2,20,82946555?
Please remember that you need to un-rar the file.?


On Sun., 4 Jul. 2021 at 12:51 p.m., Lou W7HV via groups.io<louandzip@...> wrote: Where can I find the nanoVNA-App software you speak of?? I don't find it with a web search.? Does it have a different name under which I might find it?

TNX