Re: errors of "error" models
#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/8459Sincerely, gin&pez@arg :#90.03
|
Re: Choke Series resonant frequency measurement
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
|
Re: Choke Series resonant frequency measurement
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
|
Re: New version of NanoVNA-Saver: 0.2.1
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
toggle quoted message
Show quoted text
On Sun, 22 Dec 2019, 20:30 Arie Kleingeld PA3A, <pa3a@...> wrote: 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:
Hi Rune,
Thanks for a great interface program for the NanoVNA. I have run into a problem I do not understand in carrying out a calibration using
nanovna-saver 0.2.1 (also 0.2.0). I have the frequency range set to 50 kHz
- 50 MHz. If I use the Calibration assistant the calibration is accepted
when I press Apply. However if I use the buttons, waiting enough time I
believe between stages for the scan to complete, and press "Apply" I get
the error box
" Error applying calibration
Two of short, open and load returned the same values at
frequency 50016 Hz.
!
OK "
I have repeated this sequence several times and get the same error. I don't think I am making a mistake in connecting the calibration impedances.
The calibration sequence works fine for me using the Calibration Assistant
or using NanoVNA.exe. I must be doing something stupid that is not obvious
to me.
73, Dick, W0QM
|
|
|
Re: New version of NanoVNA-Saver: 0.2.1
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:
toggle quoted message
Show quoted text
Hi Rune,
Thanks for a great interface program for the NanoVNA. I have run into a problem I do not understand in carrying out a calibration using nanovna-saver 0.2.1 (also 0.2.0). I have the frequency range set to 50 kHz - 50 MHz. If I use the Calibration assistant the calibration is accepted when I press Apply. However if I use the buttons, waiting enough time I believe between stages for the scan to complete, and press "Apply" I get the error box
" Error applying calibration
Two of short, open and load returned the same values at frequency 50016 Hz.
!
OK "
I have repeated this sequence several times and get the same error. I don't think I am making a mistake in connecting the calibration impedances. The calibration sequence works fine for me using the Calibration Assistant or using NanoVNA.exe. I must be doing something stupid that is not obvious to me.
73, 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/homeNanoVNA Files: /g/nanovna-users/filesErik, 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
|
Re: New version of NanoVNA-Saver: 0.2.1
Hi Rune,
Thanks for a great interface program for the NanoVNA. I have run into a problem I do not understand in carrying out a calibration using nanovna-saver 0.2.1 (also 0.2.0). I have the frequency range set to 50 kHz - 50 MHz. If I use the Calibration assistant the calibration is accepted when I press Apply. However if I use the buttons, waiting enough time I believe between stages for the scan to complete, and press "Apply" I get the error box
" Error applying calibration
Two of short, open and load returned the same values at frequency 50016 Hz.
!
OK "
I have repeated this sequence several times and get the same error. I don't think I am making a mistake in connecting the calibration impedances. The calibration sequence works fine for me using the Calibration Assistant or using NanoVNA.exe. I must be doing something stupid that is not obvious to me.
73, Dick, W0QM
|
Re: Choke Series resonant frequency measurement
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
toggle quoted message
Show quoted text
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 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
|
Never mind, I finally found the information I was looking for.
As usual, as soon as I post a question, I find the answer.
Larry
n0sa
|
Re: Looking for firmware with battery indica
sorted it,i followed the first link,realsed its the bottom one thats the latest on the firmware list pdf.
|
Re: QEX Magazine #tutorials.
I'm confused.? How is that legal??? The following quote is taken directly from the terms of use at librarycat.com:
"You may not post any content that violates copyright or other intellectual property law."
Please explain.
Dave?? AB7E
toggle quoted message
Show quoted text
On 12/22/2019 4:22 AM, David Wilcox via Groups.Io wrote: Or if you have the issue in question donate it to Paul W0RW¡¯s radio lending library. Then others can check it out via mail and enjoy it, even make a copy of the article for their own use. All perfectly legal.
Paul¡¯s lending library. Check it out.
|
Re: errors of "error" models
#90.02 : A Comment on [SAMoEEiVNAM] Technique - #90.00 : A Practical Introduction to our -Second- Arithmetical Method of Error Estimations in VNA Measurements : [SAMEEVNAM] 22 December 2019 - /g/nanovna-users/message/8505Hello, We are terribly sorry for the inconvenience, but we had to also notice already that this our Second Arithmetic Method : ) does not based on higher mathematics at all, since it only involves the very simple form, very easily programmable - more simple than these two simplifications are simply impossible : D - arithmetic of: #88 : the G formula - our research work has been completed 21 December 2019 - /g/nanovna-users/message/8459Specifically, this formula is used once with the Nominal Values of the Standards, as these are provided by their Manufacturers, thus resulting in a Nominal Value Z, by using the well-known formula, and then once more, with some Error Value of the Standards, as it is selected by The Common User to be within the limits posed by their Decent Manufacturers, resulting in an Error Value Zt, respectively. Finally, The Common User takes the difference (Zt - Z), extracts its real and imaginary parts and calculates the percentage differences of them. That's all. : D ) Sincerely, gin&pez@arg :#90.02
|
Hi Frank,
When an option of ARRL membership was a CD received at the end of the year,
then I took that option. This was an economic choice as the CD contained
not only QST but NCJ (no interest) and QEX. I enjoyed reading the excellent
technical articles published in QEX.
Life here in the UK is considerably more expensive that in the USA. One
just has to compare the cost of housing and gasoline. It was a shock to our
American daughter-in-law when she moved to live in the UK.
The ARRL closed the CD option and now I get the digital QST only.
I cited 13 sources in the bibliography and 114 sources in my reference
list.. My earliest QST reference was from 1916 - Tuska - The oscillating
Audion - when positive feedback was first being investigated. (I have a
copy of Black's book among the pile here). Access to patents, bound copies
of the journal of the IEE proc.IRE etc. helped enormously.
Now we must leave the NanoVNA forum for more relevant correspondence.
Phil G3SES
toggle quoted message
Show quoted text
On Sun, 22 Dec 2019 at 15:44, Frank Howell <frankmhowell@...> wrote: All,
Just know that *soon* all ARRL members will have electronic access to QEX
and NCJ issues via the ARRL.org website, although print issues will still
require a subscription.
And, be aware that there IS the Fair Use provision in the copyright law.
You do NOT need permission to quote a copyrighted work with source citation
for limited and reasonable amount. Others have cited the appropriate legal
source. I suspect Phil, that in your large dissertation (mine was two
volumes), you quoted numerous sources with citation, no?
73,
Frank
K4FMH
ARRL Asst Director, Delta Division
Editor-in-Chief, Springer (ret.)
Professor Emeritus, Mississippi State University
|
I am a bit confused on the Marker Menu and the Markers in general.
I know I can turn them on and off and move them and read the values on the screen.
I know that I can click on one and then the others show a Delta value.
What I do not understand is the >Start, >Stop, >Center, etc on the marker menu and what they do.
Any help or point to a description would be appreciated.
Larry
n0sa
|
Re: NanoVNA connected to Amazon Fire tablet
On Sun, Dec 22, 2019 at 07:07 AM, Lawrence Macionski wrote:
I bought the Amazon Fire Tablet August 23, 2019 --- Exactly 4 months ago...
===============================================================
Lawrence
According to your previous message your Amazon Fire Tablet has OS 5.6.4.0. The wiki at shows OS 5.6.4.0 is based on Android 5.1.1 Lollipop.
That explains why Google Play Store will not display the NanoVNA app on your tablet. The wiki also says your Fire Tablet is 7th generation. I believe 8th and 9th generation Fire Tablets work fine with the NanoVNA apk.
- Herb
|
gin&pez@arg
Arie Kleingeld PA3A
K4FMH