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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

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)

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/Ω & X/Ω"" 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/ω 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= ω/2π 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

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

I really dont think you wanted to send the link to all of your pictures.

Hello Francois,

Op di 5 jul. 2022 om 20:17 schreef F1AMM <18471@...>:

ω for the pulsation and ω = 2.π.f
Ω for ohms

But you used R/Ω (in "S11 R/Ω & X/Ω"), so I repeated that (did not want to
introduce something new), but indeed it is R/ω

When it happens at home, I read
Now Z = C* Ω* ( mu'+j*mu")

I understand
Z = Cω (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 = Kω (u'+ju") ??

mu is the greek letter μ (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/ Ω ) = C* ( mu'+j*mu")

I supose
Z' = Z/ ω = C ( mu'+jmu")

Correct: Z' = Z/ ω = C ( μ '+j μ ")

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/ ω ).

Do you plot Z' as a function of ω ?

Indeed, NanoVNA does that for you.

All the best,

Victor

I hate RP connectors, just for that reason.

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

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
ω for the pulsation and ω = 2.π.f
Ω for ohms

When it happens at home, I read
Now Z = C* Ω* ( mu'+j*mu")

I understand
Z = Cω (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 = Kω (u'+ju") ??

You have write :

Z is measured by the nanoVNA. By dividing the Z by , you get a value that

is:

Z' (=Z/ Ω ) = C* ( mu'+j*mu")

I supose
Z' = Z/ ω = 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 ω ?

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 / ω xC
X(L) = 2 x pi x F x L = ω x L

where ω = 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
ω for the pulsation and ω = 2.π.f
Ω for ohms

When it happens at home, I read
Now Z = C* Ω* ( mu'+j*mu")

I understand
Z = Cω (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 = Kω (u'+ju") ??

You have write :

Z is measured by the nanoVNA. By dividing the Z by , you get a value

that is:

Z' (=Z/ Ω ) = C* ( mu'+j*mu")

I supose
Z' = Z/ ω = 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 ω ?

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
Envoyé : mardi 5 juillet 2022 13:04

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


--
Dave - W?LEV

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.

As am I. Why learn something outdated and then pootentially have to releard the current version. Do it once . . . .

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

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.

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
ω for the pulsation and ω = 2.π.f
Ω for ohms

When it happens at home, I read
Now Z = C* Ω* ( mu'+j*mu")

I understand
Z = Cω (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 = Kω (u'+ju") ??

You have write :

Z is measured by the nanoVNA. By dividing the Z by , you get a value that is:
Z' (=Z/ Ω ) = C* ( mu'+j*mu")

I supose
Z' = Z/ ω = 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 ω ?

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
Envoyé : mardi 5 juillet 2022 13:04

I'm in the 'upgrade 1st' column. You are probably going to want to learn the upgrade procedure anyway and that's not tied to operating proficiency. In addition to bug fixes, newer FW will better track written documentation like menu trees.

A lot of folks, myself included, like to keep firmware current, as there are many improvements and bug fixes in the new releases. There is little that is more frustrating than trying to learn a new instrument while also dealing with bugs.
The first thing I do when I get a commercial instrument into the lab is to check that the firmware is up to date, or make it so.
When you call for tech support, the first question is usually, "what firmware revision are you running?"
73, Don N2VGU

Hello Francois,

The complex permeability of a toroid is mu=mu'+j*mu"
mu' is the real permeability (will determine the reactance of a coil) and
mu" is the imaginary permeability (will determine the resistance of the
coil).

Now Z = C* Ω* ( mu'+j*mu")
The C is depending on the physical layout of the toroid (and constant for
that toroid).

Ω is your 2*pi*f

Z is measured by the nanoVNA. By dividing the Z by , you get a value that
is:
Z' (=Z/ Ω ) = C* ( mu'+j*mu")
And thus you can measure with the NanoVNA something close to the complex
permeability of a toroid.

Does this help?

All the best,

Victor

Op ma 4 jul. 2022 om 20:47 schreef F1AMM <18471@...>:

Gerd and others,

Use the nano with the firmware that comes with it. It does most of the things a ham needs out of the box. THEN when you are very familiar with it you can update the firmware. Why is everyone so willing to mess the the basics before learning how to use a new instrument? Not the best use of a new piece of test gear, at least in my opinion.

Dave K8WPE

David J. Wilcox’s iPad

Question 1
----------

How it works is that it gives two curves that are in units of resistance/Hz. and
reactance/Hz. The shape of these curves and the frequency they cross over can be
compared with the published complex permeability (u' and u'') curves supplies by ferrite
manufacturers. When you get something similar you know the ferrite mix (75, 43, 31 etc) of
the unknown ferrite core.

Thank you for your patience. It is now much clearer. Can you tell me the diagram of the device to implement to make this measurement that interests me.

Question 2
----------
Ok. I didn't think there could be such parasitic phenomena. I redid the measurements with only a capacitor (without a series resistor). Below is the comparison between mica insulated capacitor and tubular ceramic capacitor.

it's reassuring about the nanaoVNA
Topic closed - thank you

73
--
F1AMM Fran?ois

-----Message d'origine-----
De : [email protected] [mailto:[email protected]] De la part de Roger Need via
Envoyé : lundi 4 juillet 2022 23:04

On Sun, Jul 3, 2022 at 09:38 PM, F1AMM wrote:

My question of F4HTQ having remained unanswered, I appeal to you again.

Question 1
----------
I do not understand one of the graphs of Nanovna-Saver: S11 R/ω & X/ω

I don't understand what it wants to represent, nor the units. In addition
there are two curves. It does not seem to me that the values ??are
returned to the data of the markers. Basically I don't understand anything.

I thought I answered your question in my earlier post. The author added that graph to NanoVNA Saver at the specific request of a user F4HTQ. It is ONLY useful if you are trying to determine the properties of an unknown ferrite core and if you are not doing that you can just ignore it. It is explained in this post... /g/nanovna-users/message/6996

How it works is that it gives two curves that are in units of resistance/Hz. and reactance/Hz. The shape of these curves and the frequency they cross over can be compared with the published complex permeability (u' and u'') curves supplies by ferrite manufacturers. When you get something similar you know the ferrite mix (75, 43, 31 etc) of the unknown ferrite core.

Question 2
----------

I had the bad idea to check the overall operation by putting under test,
between 1 MHz and 10 MHz, a simplistic circuit made up of a 720 PF capacitor
with a resistance of 51 Ω.

If the value of the series resistance is almost constant, this is not the case
with the value of the series capacitor. I changed the type of capacitor (mica
/ ceramic) I get exactly the same values. I even observe a resonance at 20.7
MHz, frequency where the serial impedance is worth 50.2+J1.74.

Why does the bridge produce this aberrant result.

The VNA is reporting the complex impedance (R+/-jX) at the measurement terminals (called "reference plane" ) . Your 51 ohm resistor will have some inductance due to the leads and the resistance will increase with frequency. The degree of change will be determined by the several factors like lead length/diameter and the size and type of resistor Any real world capacitor will consist of resistance, inductance and capacitance. The resistance, due to ESR and the leads, will vary with frequency. The leads will become more resistive with frequency due to the skin effect. The ESR will depend on the frequency and the dielectric. The reactance X due to capacitance will get smaller with frequency and the inductive reactance due to capacitor geometry and lead length will increase with frequency. When the two cancel out you will have a resonant condition.

When the NanoVNA calculates capacitance or inductance it is really making simplified calculations. L= X/(2*pi*Freq) and C=1/(2*pi*X*Freq). . These do not take into account that the reactance measured is due to inductance and capacitance associated with the real world component. The measured values expressed by these simple calculations are sometimes referred to as "apparent capacitance" or inductance as oposed to the underlying "actual" inductance or capacitance. . I have attached some annotated plots that show the effects. One is a 10 pF capacitor that was measured with long leads and then the leads shortened and measured again. The second is a 47 pF showing the self resonant frequency. The third is an inductor marked as 330 uH but this value is what was specified at a low frequency.

Roger

Amidon buys many of their ferrite offerings from Fair-Rite.

Dave - W?LEV

--
Dave - W?LEV