开云体育

Thanks, Rune. That SW is a downright winner. Thank you!!!!!!!

Dave - W?LEV

--

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

I would like one or two of those switches.? I live in Los Angeles.? Where did you get them, and are you willing to sell me a few?
Bob

This is the topic that lead me to the nanoVNA

Hi David
How is you test setup ? A single short wire thru the core ?
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af David F4HTQ
Sendt: 14. november 2019 23:06
Til: [email protected]
Emne: Re: [nanovna-users] NanoVNA-Saver 0.2.0

Hi All,
I add some explanations.
I asked Rune if he could add this graphic because it is very useful.
It display curves that have exactly the same shape as the complex permitivity curves (μ'r and μ''r) of the ferrite datasheets.

The values do not match those of the constructor curve ( to have the right value the software might know the exact geometry of the inductor) , but the shape is absolutely identical.

This allow to easy identify unknown ferrite core, and to better understand how to use it in a RF device.

For example, here is the true curve of material 43 of Fair rite.



And here's the one I got with NanoVNASaver


It works really well.
David, F4HTQ.

Hi Herb,

For the curve i post as example, i just made one tun of emailled wire of BN43-202 ferrite.

I also obtained accurates results with 61 and 73 ferrites materials. (I don't own 31 material).

I could post some curves this weekend.

The annoying limitation is that the measurements sent by the NanoVNA become imprecise when the reactive part of the inductance becomes too weak compared to the resistive part. This happens near 40MHz for the material 43, 6MHz for the 73 and 70MHz for the 61. You can't miss this issue because the X becomes negative, as with a capacitor!

Regards,
David, F4HTQ.

That would be permeability. Physics degree not withstanding. I never
could keep them straight!

Dave - W?LEV

On Thu, Nov 14, 2019 at 11:55 PM David Eckhardt via Groups.Io <davearea51a=
[email protected]> wrote:

Yes, what was your setup for the type 43 material permittivity measurement?

Dave - W?LEV

On Thu, Nov 14, 2019 at 10:32 PM Bob Albert via Groups.Io <bob91343=
[email protected]> wrote:

David, can you explain exactly how you got the curves? I would like to
do it also.
Bob
On Thursday, November 14, 2019, 02:06:06 PM PST, David F4HTQ <
f4htq@...> wrote:

Hi All,
I add some explanations.
I asked Rune if he could add this graphic because it is very useful.
It display curves that have exactly the same shape as the complex
permitivity curves (μ'r and μ''r) of the ferrite datasheets.

The values do not match those of the constructor curve ( to have the

right

value the software might know the exact geometry of the inductor) , but

the

shape is absolutely identical.

This allow to easy identify unknown ferrite core, and to better
understand how to use it in a RF device.

For example, here is the true curve of material 43 of Fair rite.

And here's the one I got with NanoVNASaver

It works really well.
David, F4HTQ.


-----Message d'origine-----
De : [email protected] [mailto:[email protected]] De la part
de Rune Broberg
Envoyé : mercredi 13 novembre 2019 08:23
? : [email protected]
Objet : Re: [nanovna-users] NanoVNA-Saver 0.2.0

Hi John,
my experiments in this field have been very limited - the feature was
added with the encouragement of David F4HTQ. He submitted to me an S2P

file

of a measurement of a toroid, and a curve shape:

He believed this could be approximated as R/ω and X/ω, so I implemented
it, and managed to create the following graph:

[image: image.png]

Which seemed to fit quite well, even though the units aren't exactly the
same.

So, for now, all I know how to do is: Given a permeability chart from a
manufacturer, replicate the same curve shape vs frequency using the

NanoVNA.

I hope it's useful ;-)

--
Rune / 5Q5R

On Wed, 13 Nov 2019 at 01:22, John AE5X <ae5x@...> wrote:

Now that the capability is there in the software, how would one use
the NanoVNA to check a toroid's permeability? New territory for me...
:-)

--

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

--

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

Yes, what was your setup for the type 43 material permittivity measurement?

Dave - W?LEV

On Thu, Nov 14, 2019 at 10:32 PM Bob Albert via Groups.Io <bob91343=
[email protected]> wrote:

David, can you explain exactly how you got the curves? I would like to
do it also.
Bob
On Thursday, November 14, 2019, 02:06:06 PM PST, David F4HTQ <
f4htq@...> wrote:

Hi All,
I add some explanations.
I asked Rune if he could add this graphic because it is very useful.
It display curves that have exactly the same shape as the complex
permitivity curves (μ'r and μ''r) of the ferrite datasheets.

The values do not match those of the constructor curve ( to have the right
value the software might know the exact geometry of the inductor) , but the
shape is absolutely identical.

This allow to easy identify unknown ferrite core, and to better
understand how to use it in a RF device.

For example, here is the true curve of material 43 of Fair rite.




And here's the one I got with NanoVNASaver




It works really well.
David, F4HTQ.


-----Message d'origine-----
De : [email protected] [mailto:[email protected]] De la part
de Rune Broberg
Envoyé : mercredi 13 novembre 2019 08:23
? : [email protected]
Objet : Re: [nanovna-users] NanoVNA-Saver 0.2.0

Hi John,
my experiments in this field have been very limited - the feature was
added with the encouragement of David F4HTQ. He submitted to me an S2P file
of a measurement of a toroid, and a curve shape:





He believed this could be approximated as R/ω and X/ω, so I implemented
it, and managed to create the following graph:

[image: image.png]

Which seemed to fit quite well, even though the units aren't exactly the
same.

So, for now, all I know how to do is: Given a permeability chart from a
manufacturer, replicate the same curve shape vs frequency using the NanoVNA.

I hope it's useful ;-)

--
Rune / 5Q5R

On Wed, 13 Nov 2019 at 01:22, John AE5X <ae5x@...> wrote:

Now that the capability is there in the software, how would one use
the NanoVNA to check a toroid's permeability? New territory for me...
:-)

--

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

Yes, for whatever reason you got a lower apparent reflection coefficient on the left-hand unit.
This is reflected (so to speak) in the noisier-looking phase trace.

Results with an S21 measurement of a fairly lossy DUT (say, about a 30 to 40 dB attenuator)
should be more revealing of the relative merits of the two units.

Dana (K8YUM)

More images, a puzzle, and some explanation...like real estate, it may be location, location, location
To begin, it's true that I was open on CH1, but the image shows that both devices were displaying only CH0.
Perhaps I should have CH1 capped at 50 O? Not sure, but will test to see what difference...

Now puzzle: I arrived back and decided to do some checks. I was surprised to see change to LOGMAG signals on H. H_Q-0.4.3_20191114_173035c.jpg
I recal, and duplicated the test, being careful to lay out the 3.5m of RG316 with no overlaps. Surprised to see H_Q-0.4.3_20191114_174614c.jpg, because now the phase had a lot of jitter.
As I was moving the unit off the desk to take a better picture, the signals cleared up. Not sure why that is so...No running electronics on desk, but the desk is covered with a dark tempered glass...it may have metal in it.
Seeing the effect of raising the H VNA from the desk, I wondered what the AURSINC unit would look like...in my original post, it was very much worse. But see AURSINC_cf_H_Q-0.4.3_20191114_174939.jpg.
I didn't recal the AURS. The phase is now cleaner, and closer to H, but there are those odd humps in LOGMAG.
I note there is a 180 degree phase difference twixt AURS and H in both my original post and this one, and don't know if that is important.

I am preparing to use this in the field, so I want to know what my expectations are. I also am trying to figure out if it is possible to put this at the mid-point of a 130 ft. plus dipole fed by plastic window "ladder line" to measure feed point impedance vs frequency and how it varies as we pull up the antenna from ground level to full height. The alternative is to cal to the end of the ladder line, but I don't know how that will work...to new to VNA.

I also plan to test identical configurations using a laptop|USB and a mobile|tablet|USB to see how data gathering this way affects the displayed data.
--
73 de Rich NE1EE
On the banks of the Piscataqua

Yes, for whatever reason you got a lower apparent reflection coefficient on the left-hand unit.
This is reflected (so to speak) in the noisier-looking phase trace.

Results with an S21 measurement of a fairly lossy DUT (say, about a 30 to 40 dB attenuator)
should be more revealing of the relative merits of the two units.

Dana (K8YUM)

On Thu, Nov 14, 2019 at 02:06 PM, David F4HTQ wrote:

" The values do not match those of the constructor curve ( to have the right value the software might know the exact geometry of the inductor) , but the shape is absolutely identical.
This allow to easy identify unknown ferrite core, and to better understand how to use it in a RF device.

For example, here is the true curve of material 43 of Fair rite.
And here's the one I got with NanoVNASaver

------------------------------------------------------------------------------------------------------------------------------------------------

David that helps to explain the purpose of the new charts. I was wondering if you might answer the following questions when you get some time.

1. I visited your web site but did not see an article about ferrite core measurements. What test set-up did you use to generate the Complex-Perm-vs-Freq plots?

2. Since you used the shape of the curves rather than the permittivity values to identify the type material, do you have atypical plots for different material types (i.e. 31, 43, 61) and how well did they match the corresponding Fair-rite corporation curves?

I also have accumulated numerous ferrite material over the years. Some marked but the majority unmarked. I'd love to have a way of sorting them by type and doing so visually by the shape of their curve, as you propose, would be good enough for me.

Regards,

- Herb

I have 50 pieces of it (could not buy less) . I get them on Ebay search string "50PCS Slide Switch SK12D07VG2 Toggle Switch 2mm Stents Toggle Switch UK".
U must have exact the right type. You can mail me a PM.
on1bes Herman

There are only two kinds of software : the DFU files for Firmware install, and the different software(s) for use the NanoVNA on laptop/PC.
And you can find tim all in the Wiki.
on1bes

Hi David,
the .dfu files are firmware versions for the NanoVNA.

There are several Windows apps available for the NanoVNA. I made
NanoVNA-Saver:



Other options are NanoVNASharp and TAPR VNA.

Good luck with your NanoVNA :-)

--
Rune / 5Q5R

I Bob,
It very basic.
I made one turn on BN43-202 ferrite core and connect it to CH0 of Nano VNA.
And put frequency range to 100Khz -> 30MHz with logarithmic scale on all axes.
David.

Are there any and where online do I find them? The file extensions I am seeing are "DFU" which is an Apple thing.

No tthat I particularly believe in Windows, but all my engineering and scientific applications run under Windows and not Apple.

This is my first post to this group, so please forgive me if this has been asked previously. .
--
Dave - W?LEV

? is the magnetic analog of ε, the dielectric constant. ?0 is the
permittivity of free space ε0 is the permeability of free space. The
?r which you are seeking is the relative permitivity of the ferrite (or
what ever) and represents a multiplier to ?0.

Dave - W?LEV

--

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

David, can you explain exactly how you got the curves?? I would like to do it also.
Bob

On Thu, Nov 14, 2019 at 01:52 PM, Larry Naumann wrote:

Thanks for all the good links, looks like I have a lot of reading to do. I am trying to learn all this stuff and it takes me awhile to get my head wrapped around all of it.

------------------------------------------------------------------------------------------------------------------------------

Larry,
Don't let the terms overwhelm you. If you've never used a VNA before, it can be a "can't see the forest for the trees" kind of thing, but depending on what you want to do with the NanoVNA there are a lot of information you can ignore until a problem presents itself where you actually need to learn the terms.

I worked in the electronics industry for 30 years and about the only time I actually needed to apply the terms and formulas you referred to was when I was designing filters or matching networks. If you are still in school and studying electrical engineering you will definitely need to be familiar with the terms. If you just want to check the VSWR of your antennas then you can ignore them until you want to broaden your knowledge.

- Herb

Hi Larry,
You can found some details on the document linked to this message.
David.