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I figured out how the Marker Span button works.?

You need to have TWO or more markers (M1-M4) enabled for the Span button to work.?

Essentially, when you press the Marker Span button, the last two ACTIVE markers will be used to set the frequency span to the current upper and lower marker freq values.??

It doesn't matter if you have 3 markers displayed. If the last two you moved were M2 and M3 and even if M2 is at a higher frequency than M3, the span will be set using the lowest and highest values of the 2 markers.?

I hope this helps with using the markers on the NanoVNA.?

Cheers and Holiday Wishes to All !
Larry. VE3LRI


On Sun, 22 Dec 2019 at 12:37 PM, Larry Rothman<nlroth@...> wrote: Hi Larry,
I can explain stop, start and centre but not span:

Essentially, these commands allow you to set the frequency range or span using the position of the active marker. Make sure the current onscreen frequency span is greater than what you actually require so you can use the marker settings to 'zoom-in'.

For simplicity, enable only one marker.

Now place (drag) the marker to the starting frequency of the range you want to investigate.? You can read the marker freq onscreen at the upper right area of the display as you move it.

Open the Marker menu and click the Start button and you will see the start freq at the lower left of the display change to the current marker freq.
Now move the marker to the maximum frequency of the range you're interested in and again, open the Marker menu and press the Stop button.

The upper frequency shown at the lower right of the display will now change to that value.? You now know how to set the start and stop frequencies using the marker menu.

To set the span, you will use the Center menu button.? You set the start freq as before but the second entry will be to move the marker to centre frequency you're interested in and press the Center menu button.? This will automatically adjust the start and stop frequencies to be equal, either side of of the center.

As for the Span button, it just turns green when pressed and does not seem to do anything. I will have to look at the source code to see what that's about.

I hope this helps. I will update the user guide with this information soon.

Regards
Larry

Here's a thought.? If you and others are so convinced that you have the moral high ground here, why don't you ask the author of the article for a summary via email (or a pdf scan like the other guy wants) instead of asking a third party to do so?

Dave?? AB7E

How about giving us the gist of his conclusion about it?
Basically a thumbs-up, thumbs-down, or just what he liked and what he didn't like. Don't do any quoting...put it in your own words.

Just a thought...

This link was posted on the NanoVNA Facebook group.

Very interesting tests of homebrew Male and Female SOL calibrators. He compared 1, 2 and 3 resistor loads.

Hi Terry, it's a long time ago.. Because the seach problems of the replaced LCD, i post the link for Ali. You must choose the version with touch. But it is in Dutch. Search the exact same LCD in your own language site by Ali.
,searchweb201602_6,searchweb201603_53

Can't we cease belly aching about *one article*? Agilent/Keysite has
excellent tutorials on the care and feeding of a vector network analyzer.
Just because it isn't the NANOVNA, the same theory applies.






And another very general treatment with nothing beyond simple high school
algebra:




All these, and others, are open, published, and available free of charge.
Open to education and learning on the www. Have at it and quit belly
aching over *one single article!*

Dave - W?LEV

On Sun, Dec 22, 2019 at 10:58 PM Frank Howell <frankmhowell@...>
wrote:

Andy,

Agreed! Even copying and pasting the Abstract with this info is fair use
as publishers frequently made titles and abstracts publicly available.

Personally, I’ve sent folks PDFs of articles they stated they would like
to read because they are actively studying the topic. This IS fair use,
just as going to a library and photocopying an article out of a print
magazine or journal is. Ask any professional librarian!

In my case, I have an active paper with two local E.E.s comparing several
NanoVNA devices with the MiniVNA, the Tom Baier VNA from Sdr-Kits, an
Agilent FieldFox, and a high end R&S VNA with precision loads and several
commodity DUTs that ham operators would often use. We will complete the
measurement schedule after the Holidays but will have to see if we offer
anything beyond this new QEX article.

It’s completely legal and ethically being a colleague if someone on this
list sends me either images of the article pages or a scanned PDF if that’s
easier. I’m good on QRZed and my email is here, too.

73,

Frank
K4FMH

--

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

Andy,

Agreed! Even copying and pasting the Abstract with this info is fair use as publishers frequently made titles and abstracts publicly available.

Personally, I’ve sent folks PDFs of articles they stated they would like to read because they are actively studying the topic. This IS fair use, just as going to a library and photocopying an article out of a print magazine or journal is. Ask any professional librarian!

In my case, I have an active paper with two local E.E.s comparing several NanoVNA devices with the MiniVNA, the Tom Baier VNA from Sdr-Kits, an Agilent FieldFox, and a high end R&S VNA with precision loads and several commodity DUTs that ham operators would often use. We will complete the measurement schedule after the Holidays but will have to see if we offer anything beyond this new QEX article.

It’s completely legal and ethically being a colleague if someone on this list sends me either images of the article pages or a scanned PDF if that’s easier. I’m good on QRZed and my email is here, too.

73,

Frank
K4FMH

OK,

I am a buyer. just tell me where to send the money!


Le ven. 20 déc. 2019 à 16:58, Martin via Groups.Io
<martin_ehrenfried@...> a écrit :

/g/nanovna-users/message/3872
--
Regards,

Martin - G8JNJ

You don't need a test jig to measure plate chokes.

They are influenced by the layout in the amplifier.

You need to measure the choke in it's operating position.

--Shane
KD6VXI

Thanks Larry, I didn't get that from the manual but sounds good.
Thanks
Larry
n0sa

#90.03: A Note on [SAMoEEiVNAM] Programming

In the usual case of the Triplet of Standard Nominal Value (-1, 0, +1), it may be
proved that it is programmatically advantageous to use different formulas for
the computation of G and Gt, that is of G_mini and of complete G, respectively:




#53 : Upgrade : The [LeastVNA]
17 October 2019 - /g/nanovna-users/message/5110

#88 : the G formula - our research work has been completed
21 December 2109 - /g/nanovna-users/message/8459

Sincerely,

gin&pez@arg

:#90.03

Thanks for all the replies. I have a box of chokes that I will set up and sweep. The plan is to build a test jig which will be a square tube with about 33mm of clearance on each side. This will ensure repeatability. I have been struggling to wind a good plate choke that covers all the ham bands including the warc bands. I just wanted to be sure that i was not wasting wire and using the wrong technique.

Henry

Bob,
thank you for clarification. I have measured a coil in this way( connected
only to CH0). Attached Smith chart and R, X graph.
The resonance can be seen easily around 12 MHz. However, in my case it is a
parallel resonance, impedance is very high.
For the plate choke we need the series resonance[s] which can cause serious
trouble in tube PA.

My question was not about the method, but about the accuracy.
Is the stray capacitance of the NanoVNA shifting the self resonance
frequency of the coil ?

73 Ady

[image: Coil - Smith.png]
[image: Coil - R & X.png]


On Sun, Dec 22, 2019 at 7:53 PM Bob Albert via Groups.Io <bob91343=
[email protected]> wrote:

The resonance of a choke is measured by connecting it to the S0 port.
You select Smith chart and, with the frequency at a low value you read the
inductance on the screen, with the plot being a dot at the left edge.
(First you select S0 reflection mode.)
Then you sweep the frequency up until the chart becomes a circle. The
point where it passes halfway around, to the right edge, is the resonant
frequency. You carefully adjust the frequency until the inductance reading
on screen switches to capacitance. That's resonance.
Bob K6DDX
On Sunday, December 22, 2019, 08:00:43 AM PST, Ady, YO2NAA <
yo2naa@...> wrote:

Will the reactance of NanoVNA's channels influence the resonant
frequencies of the choke, or the calibration process is removing this
influence?
If the influence is present, what method will minimize it the most?
Should the choke be measured mounted in the PA, to include the influence of
the neighboring objects?

73 Ady YO2NAA

On Sun, Dec 22, 2019 at 2:34 PM Jim Potter <jpotter@...> wrote:

To find a series resonance you are looking for the frequency where the
impedance is a minimum.
All three techniques you suggest will work.
1. Series between two ports, look for the frequency of maximum S21
2. Shunt, you only need 1 port. Look for the frequency of a dip in S11.
Don't connect Port 2
3. With two coupling coils the result will be like #1, The frequency for
maximum S21 is the self resonance
4. With one coupling loop the series resonance will be the minimum in

S11,

like #2. This is pretty much what you are doing with the grid dip meter,
looking for maximum energy absorption,

Try all of these techniques to see the difference. That's one of the

great

thing about the nanoVNA it's a great educational tool at an affordable
price.

73 de K9GXC, Jim

Hi,
I have not used the latest versions, so I could be wrong, but the way I
remember it, is that you have to run a manual scan before you use the
buttons.
So, leave the port open, run a scan, press the open button, connect the
short, run a scan, press tbe short button, connect the load, run a scan,
press the load button, then apply the cal.

Askild

Garry

In /g/nanovna-users/message/8494 they provide the proof they are mathematically the same.

--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

I had the same reports.

But... the calibration runs well? (both 0.2.0. and 0.2.1) using the Calibration assistant.

73

Arie PA3A


Op 22-12-2019 om 19:00 schreef Dick W0QM:

Garry

The issue is the new proposed vna formula and the old SOL calibration approach are mathematically the same.
Apart from discovering an elegant notation nothing will change in my view
What you call Cal correction is also identical
Even a partial differentiation of both approaches will be the same as they are mathematically the same


--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

Is this the NanoVNA's Great Nothingburger Thread of 2019 ?

After all this fuss, bugger all of any use has come out of it.

All that was needed was for someone to say "hey, I read the article. It seems to give a general thumbs up and compares
quite well to a $50000000000 VNA that a friend of a friend has" etc.

What a load of crap ;-)

Merry Xmas to one and all.

73 de Andy

Hello Erik;

My understanding is that this begins as an entirely closed form solution with a computationally exact result. All uncertainties (including those included in the standards) are accounted for in the solution. Only the unavoidable physical uncertainties in the measurements contribute to inaccuracies in the results. The degree of inaccuracy is dictated by the degree users wish to allow and use for their standards, the frequency accuracy and resolution of their source, and the computational precision (bits) of the computer allowed and used for performing the calculations themselves.

Indeed; the proof would be expected to result in an identical outcome, but only when identical inputs are employed. The root of both solutions appear to be based on Hackborn’s work published in the late 1960’s.
Note that Hackborn’s assertion was that the “Network Analyzer System simply leaves the errors in the system, but measures and remembers them.” Note also that this new solution completes the task in closed form. It does not compute a result and then externally modify that result with a nonlinear correction algorithm that attempts to model systemic behaviors deemed to be predictable uncertainties, when in fact the corrections introduce compensations which themselves are uncertainties that cannot be predicted with any certainty in their accuracy or precision.

My apologies if the above sounds a bit like double-talk, but it represents (in words)... “my interpretation” of the research being presented and explained by the authors GIN&PEZ@arg. All are welcome to review the work they have made openly available to this forum, perform their own scrutiny of the integrity and soundness of their assumptions, derivations, proofs, computations, and conclusions in sufficient detail to satisfy their own comfort level of understanding, and draw their own conclusions.

That said; I don’t see any fundamental restriction to modification of the existing algorithms by embedding the
characterized cal standard definitions into the solution, and omitting cal correction processing that would otherwise follow the computations after the fact. I would differ any conclusion in that regard to the authors of this work.

--
73

Gary, N3GO

Phil,

I get the annual publications DVD instead of subscribing because it’s cheaper. I’m also an RSGB member but buy those digital issues on DVD, too. So I don’t have the current QEX issue either.

Note to you and other Group members: the ARRL will *soon* give access to digital issues of both QEX and NCJ (as well as QST and the new On the Air magazine) to current members. Paper issues will still require a subscription.

It behooves us all to both respect copyright and patent laws but to be knowledgeable of the legal fair use provisions. It doesn’t help by being an uninformed copyright police as that merely propagates ignorance. I can tell you that the ARRL is reasonable flexible in the use of a single article among hams. They even declined to prosecute the now defunct Antennex proprietor, Jack Stone (now SK?) who was openly selling access to L.E. Cebik’s ARRL articles! What Stone did not realize was that an author turns over copyright ownership to the publisher upon publication, with rare exception. Nevertheless, Steve Ford at the ARRL told me that they would raise an official fuss over that because they were “old” articles.

I’ve founded two scientific journals at major publishers as well as a book series, edited three journals, and published many articles in peer reviewed journals. I’ve served on patent and copyright committees at universities, and, unfortunately, was involved in an intellectual property law suit which was settled out of court in my favor. I have advised lawyers and one Attorney General on software patent and copyright law. In a forum like this one, it IS important for us all to accurately recognize the legal and ethical ground rules involving intellectual property. This most active and innovative group has experienced few caustic squabbles. Knowing what’s legal is one element if keeping it that way.

Thanks to all for making this a terrific group on the NanoVNA!

Frank