On Tue, Jul 5, 2022 at 09:29 PM, F1AMM wrote:
Hello
I have very little experience with toroids. I made some RUTHROFF transformers
but nothing more. On my cores, I note that the Al is not constant. Is this
normal ?
Yes the Al will vary with frequency for ferrite toroids. The reason is that the permeability of the ferrite toroid varies with frequency and the Mix (31,43, 75) etc. has a significant effect. Powdered iron Al only varies slightly with frequency. Most of the online ferrite toroid calculators only provide good results at low frequencies. Here is an excellent online calculator for you to try >> Roger
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On Wed, Jul 6, 2022 at 06:03 AM, F1AMM wrote:
It's a pity that your pages are not in HTML; it would have allowed Chrome to
translate them to me in French, online. In English, I can't follow.
Use the deepl translator. It will translate pdf files and keep them in the same format as the original. Attached is a translation to French of one of Arie Kleingeld PA3A English articles Roger Here is
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Re: nanovna-saver/displayed charts/S11 R/¦Ø & X/¦Ø (?? / Hz)
And, speaking of Smith Charts, if you haven't yet discovered SimSmith, give
it a try. It's free.
There is also an excellent tutorial linked from that site.
Dave - W?LEV
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On Wed, Jul 6, 2022 at 4:04 AM F1AMM <18471@...> wrote: Thank you Victor
Hi there
I did well to tell you clearly what I did not understand. Our linguistic
difference plus character encoding problems had greatly scrambled the
transmission. The ? which had been transformed into mu was formidable.
The ""S11 R/¦¸ & X/¦¸"" is what is written on the graph of nanovna-saver
In summary what I understood:
From S11, nanovna-saver calculation Z
When you write Z'=Z/¦Ø you are using the real Z or the reduced z=Z/Zc where
Zc is the normalization impedance (50 ?).
Then nanovna-saver draws the graph of Z' as a function of F= ¦Ø/2¦Ð by
separating the real part from the imaginary part.
I do some development in C#. I wrote a grinder to, from a CSV, draw a
graph in a .DXF The grinder was in fact to make topographic plotting. These
.DXF (like .DWG but ASCII) I manipulate them with nanoCAD, a version of
which is free. It turns out that in the Smith chart the rectangular
coordinates of the chart (horizontal and vertical) are the coordinates of
S11 (the normalized reflection coefficient with respect to Zc). I have a
Smith chart in bitmap as well as a vectorized chart in my .DXF and I can
superimpose quite easily:
-Theoretical curves, derived from calculations
-Measurements, by processing nanovna-saver .S1P files
It is with sed I transform the .S1P into .CSV I can control this .CSV in
Excel and do calculations on it. It is a very powerful aid.
73 QRO
--
F1AMM Fran?ois
-----Message d'origine----- De la part de Victor Reijs
Envoy¨¦ : mardi 5 juillet 2022 23:13
-- *Dave - W?LEV* *Just Let Darwin Work*
--
Dave - W?LEV
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I have a lot of bad luck with Adobe. I had a CS3 version with Acrobat 8 pro (+ license) but it refuses to work. With Adobe it's hard problems. It is therefore insoluble for me to translate your .pdf and it is a pity.
The EZNEC notice is provided, among other things, in Word (.doc). It's impeccable: I converted it into HTML and Google translated it for me into almost perfect French. At least with Google it works.
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Hi,
You can translate it doing the following:
?- Open the document with Adobe Acrobat
- Select the whole text and do copy (Ctrl-C)
- in your navigator go to go to
- In the left panel copy the original text
- In the right panel select your language (i.e French). The translated text will appear there.
- Select the translated text, copy it to your favorite word processor and paste it there.
Now you can correct the translated text to make it more understandable and even you can add the pictures from the origin.
Let me know if you have any difficulty with this.
Regards,
Ignacio EB4APL
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El 06/07/2022 a las 15:03, F1AMM escribi¨®: It's a pity that your pages are not in HTML; it would have allowed Chrome to translate them to me in French, online. In English, I can't follow.
thanks anyway
--
El software de antivirus Avast ha analizado este correo electr¨®nico en busca de virus.
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It's a pity that your pages are not in HTML; it would have allowed Chrome to translate them to me in French, online. In English, I can't follow.
thanks anyway
|
Hi,
I wrote several articles on nanoVNA measurements.
You can find them in English here:
There's also a part about determening toriods, mu's and AL.
73
Arie PA3A
Op 4-7-2022 om 18:51 schreef tomas.geci@...:
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Dear OM, I'm interested about various measurements with NanoVNA but now I'm fighting with some fundamental questions not related only to nano VNA. but still unable to find answers, even after reading a lot of articles (for example k9yc, palomar engineers, and not only...)
- when I will try to determine ferrite core material by inductance and AL value, how can I be sure about right frequency for inductance? inductance could vary with frequency (various permeability) and then my AL value calculation could be wrong.
- I read somewhere that chokes need higher AL value then transformers. Why chokes requires higher AL value and transformers lower? It is because in chokes big AL value means high inductance with small amount of winding and wire and then high impedance for common mode currents with good efficiency?
Many thanks for answers, hope I will find an answer even when it is not simple topic ?
sources which I used:
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Re: Perfect SWR with dummy load, but huge with antenna
I agree.? It matters what you consider a good antenna.? We hams tend to want to see a 1:1 VSWR as a good value, but in the commercial world a VSWR of 1.5:1 (14dB RL) is considered acceptable.? Just look at the spec sheets of a commercial antenna and you will usually see 1.5:1 listed as Maximum VSWR.? As long as most commercial antennas sweep 14dB return loss or better over the design bandwidth of the antenna it would generally be considered good.
Joe, K1ike
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On 7/6/2022 12:34 AM, Clyde Lambert wrote: Just being a commercial antenna does not mean it is a good antenna.
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Re: Perfect SWR with dummy load, but huge with antenna
Fitst check continuity before all with and without short circuit on the
antenna itself!
73 Olivier F6CNG
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Le dim. 3 juil. 2022 ¨¤ 09:21, Lucian <lucian@...> a ¨¦crit : Thanks, but you were too quick to dismiss the human factor..
It wasn't until this morning that I realised the antenna is rp-sma female
and the nanovna is sma female.. They will screw in perfectly, yet no core
contact... facepalm.
I'll need to buy some adapters.
Have a nice day!
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Re: Traces refresh rate slows down with fw 1.0.69
#nanovna-h4
I understand these comments but have read so many emails where the questioner was advised to go back to a certain firmware because the ¡°latest greatest¡± wasn¡¯t working. Just my opinion. Some are luckier than others. I tend to be unlucky with upgrades.
Dave K8WPE
David J. Wilcox¡¯s iPad
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On Jul 5, 2022, at 8:00 PM, Donald S Brant Jr <dsbrantjr@...> wrote:
?But old firmware DOES have "broke" stuff in the form of bugs, etc., that is why the authors push out the new releases.
73, Don N2VGU
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Re: Perfect SWR with dummy load, but huge with antenna
Just being a commercial antenna does not mean it is a good antenna. If you want to make sure the NanoVNA is either hood or bad, check out the antenna exactly the same way you did with the NanoVNA.
I have questioned the results of my NanoVNA but proved it correct with my four other antenna analyzers.
Clyde Lambert KC7BJE
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Hello
I have very little experience with toroids. I made some RUTHROFF transformers but nothing more. On my cores, I note that the Al is not constant. Is this normal ?
TORUS
====
Outside diameter ? 10 mm
Inner diameter ? ~ 5 mm
height 5mm
Self of 33 turns of ? 0.1 mm
--------------------------------------
Bridge measurement BF Z serie
120Hz: 36.75?H 0.443 Ohms
1kHz: 36.34?H 0.447 Ohm
10kHz: 36.08?H 0.455 Ohms
100kHz: 35.91?H 0.635 Ohms
Self of 21 turns of ? 0.2 mm
--------------------------------------
Bridge measurement BF Z serie
120Hz: 8.081?H 0.0764 Ohms
1kHz: 8.122?H 0.0764 Ohm
10kHz: 8.112?H 0.0771 Ohms
100kHz: 8.084?H 0.112 Ohms
Calculation of aL ? (it-is good ?)
=============
Self 33 turns: 33 nH/turn?
Self 21 turns: 18 nH/turn?
73 QRO
F1AMM (Fran?ois)
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Re: nanovna-saver/displayed charts/S11 R/¦Ø & X/¦Ø (?? / Hz)
Thank you Victor
Hi there
I did well to tell you clearly what I did not understand. Our linguistic difference plus character encoding problems had greatly scrambled the transmission. The ? which had been transformed into mu was formidable.
The ""S11 R/¦¸ & X/¦¸"" is what is written on the graph of nanovna-saver
In summary what I understood:
From S11, nanovna-saver calculation Z
When you write Z'=Z/¦Ø you are using the real Z or the reduced z=Z/Zc where Zc is the normalization impedance (50 ?).
Then nanovna-saver draws the graph of Z' as a function of F= ¦Ø/2¦Ð by separating the real part from the imaginary part.
I do some development in C#. I wrote a grinder to, from a CSV, draw a graph in a .DXF The grinder was in fact to make topographic plotting. These .DXF (like .DWG but ASCII) I manipulate them with nanoCAD, a version of which is free. It turns out that in the Smith chart the rectangular coordinates of the chart (horizontal and vertical) are the coordinates of S11 (the normalized reflection coefficient with respect to Zc). I have a Smith chart in bitmap as well as a vectorized chart in my .DXF and I can superimpose quite easily:
-Theoretical curves, derived from calculations
-Measurements, by processing nanovna-saver .S1P files
It is with sed I transform the .S1P into .CSV I can control this .CSV in Excel and do calculations on it. It is a very powerful aid.
73 QRO
--
F1AMM Fran?ois
toggle quoted message
Show quoted text
-----Message d'origine----- De la part de Victor Reijs Envoy¨¦ : mardi 5 juillet 2022 23:13
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Re: Traces refresh rate slows down with fw 1.0.69
#nanovna-h4
But old firmware DOES have "broke" stuff in the form of bugs, etc., that is why the authors push out the new releases.
73, Don N2VGU
|
Re: Perfect SWR with dummy load, but huge with antenna
I really dont think you wanted to send the link to all of your pictures.
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On Sat, Jul 2, 2022 at 9:01 PM Lucian <lucian@...> wrote: Hi,
Just bought a Nanovna-h (0.4.5-4-g96e7efe firmware) and calibrated it,
tuned the display to only show the SWR, however while I am getting a
perfect SWR of 1 with the dummy load, I get a SWR in the hundreds or
thousands with the antenna.
The antenna is a commercial and tested LoRA 868 MHz one and this is indeed
what I am testing for, yet the Nanovna reports huge SWR.
Did I buy a dud or am I looking at the wrong things?
A few pictures here to see what I mean:
Thanks!
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Re: nanovna-saver/displayed charts/S11 R/¦Ø & X/¦Ø (?? / Hz)
Hello Francois, Op di 5 jul. 2022 om 20:17 schreef F1AMM <18471@...>:
¦Ø for the pulsation and ¦Ø = 2.¦Ð.f
¦¸ for ohms
But you used R/¦¸ (in "S11 R/¦¸ & X/¦¸"), so I repeated that (did not want to introduce something new), but indeed it is R/¦Ø
When it happens at home, I read
Now Z = C* ¦¸* ( mu'+j*mu")
I understand
Z = C¦Ø (mu'+jmu")
Correct.
You said
The C is depending on the physical layout of the toroid (and constant for
that toroid).
Ok but what is m ? why 'm' is not in C as
Z = K¦Ø (u'+ju") ??
mu is the greek letter ¦Ì (so not m*u;-) You have write :
Z is measured by the nanoVNA. By dividing the Z by , you get a value that is:
Z' (=Z/ ¦¸ ) = C* ( mu'+j*mu") I supose
Z' = Z/ ¦Ø = C ( mu'+jmu")
Correct: Z' = Z/ ¦Ø = C ( ¦Ì '+j ¦Ì ")
Z is calculated by the nanoVNA thrue S11 i suppose
What do you do with Z'
Z' is also calculated by NanoVNA Saver (it is whe graph you did/do not understand: Z/ ¦Ø ). Do you plot Z' as a function of ¦Ø ?
Indeed, NanoVNA does that for you. All the best, Victor
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Re: Perfect SWR with dummy load, but huge with antenna
I hate RP connectors, just for that reason.
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Re: Traces refresh rate slows down with fw 1.0.69
#nanovna-h4
If it ain't broke, don't fix it. At least not until you know it well enough to know what needs to be fixed. I have had too many cases where a software update broke more than it fixed.
SherpaDoug WA1UWP
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Re: nanovna-saver/displayed charts/S11 R/¦Ø & X/¦Ø (?? / Hz)
I have to use translate.google.com to write you and chrome to read you. In the message there are writing conventions that I do not understand. In addition we have special character encoding problems We use ¦Ø for the pulsation and ¦Ø = 2.¦Ð.f ¦¸ for ohms When it happens at home, I read Now Z = C* ¦¸* ( mu'+j*mu") I understand Z = C¦Ø (mu'+jmu") You said The C is depending on the physical layout of the toroid (and constant for that toroid). Ok but what is m ? why 'm' is not in C as Z = K¦Ø (u'+ju") ?? You have write : Z is measured by the nanoVNA. By dividing the Z by , you get a value that is: Z' (=Z/ ¦¸ ) = C* ( mu'+j*mu") I supose Z' = Z/ ¦Ø = C ( mu'+jmu") Z is calculated by the nanoVNA thrue S11 i suppose What do you do with Z' Do you plot Z' as a function of ¦Ø ? I put some files in a zipfile that you can download here. Could, concretely, set up what material it is Good night. Hear it is 20 o'clock I suppose I should use words, only, and not Greek letters. So: X(C) = 1 / [2 x pi x F x C] = 1 / ¦Ø xC X(L) = 2 x pi x F x L = ¦Ø x L where ¦Ø = frequency in radians / second You can do the algebra for the variables you want to solve for. I don't know if this helps. I've found the translators can not deal with technical subjects too well. It's the best we have, though. Dave - W?LEV On Tue, Jul 5, 2022 at 6:17 PM F1AMM <18471@...> wrote: Does this help?
Victor Hello
Nothing is simple for me. In addition, with age (73), I still understand
so quickly but you just have to explain myself longer :).
I have to use translate.google.com to write you and chrome to read you.
In the message there are writing conventions that I do not understand. In
addition we have special character encoding problems
We use
¦Ø for the pulsation and ¦Ø = 2.¦Ð.f
¦¸ for ohms
When it happens at home, I read
Now Z = C* ¦¸* ( mu'+j*mu")
I understand
Z = C¦Ø (mu'+jmu")
You said
The C is depending on the physical layout of the toroid (and constant for
that toroid).
Ok but what is m ? why 'm' is not in C as
Z = K¦Ø (u'+ju") ??
You have write :
Z is measured by the nanoVNA. By dividing the Z by , you get a value that is:
Z' (=Z/ ¦¸ ) = C* ( mu'+j*mu") I supose
Z' = Z/ ¦Ø = C ( mu'+jmu")
Z is calculated by the nanoVNA thrue S11 i suppose
What do you do with Z'
Do you plot Z' as a function of ¦Ø ?
I put some files in a zipfile that you can download here.
Could, concretely, set up what material it is
Good night. Hear it is 20 o'clock
--
Fran?ois
-----Message d'origine----- De la part de Victor Reijs
Envoy¨¦ : mardi 5 juillet 2022 13:04
-- *Dave - W?LEV* *Just Let Darwin Work* -- Dave - W?LEV
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Re: Traces refresh rate slows down with fw 1.0.69
#nanovna-h4
On Tue, Jul 5, 2022 at 11:24 AM, F1AMM wrote:
Why
It is very simple. It often happens that the update of an on -board ?
software goes wrong and that we can no longer go back. It is traumatic.
You can dump current firmware on NanoVNA Use DFU mode and Upload Action (and set firmware filename) For load new firmware need use Upgrade Action and select file.
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Roger Need
Arie Kleingeld PA3A
David Wilcox K8WPE
Clyde Lambert
Donald S Brant Jr
Douglas Butler