Re: SWR readings off scale
Sounds like a calibration issue.
Mine will correctly show 1.1:1 numerically and graphically, I just checked.
73 de Andy
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Hi All,
I have been subscribed to this group for quite a few weeks now, but this is my first posting.
Why? Because it has taken me that long to read through all the previous posts!
Anyway, I have not seen this subject before:
Being an licensed amateur SWR, means much more to me than return loss, which because
of my background I asssociate more with TV equipmentt, so I was a little disappointed to find
that the lowest graphical reading is about 1.3:1. The numeric readout at the top shows the
figure, but the graphical result would be much more useful for making adjustments.
Is this a feature that "comes with the model sir", or is there an adjustment that I have missed?
As a new user I do have other questions, but that is quite enough for now.
Thank you
Tony (G3PTD)
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Re: NanoVNA AURSINC v H, Q-0.4.3, images
On Fri, Nov 15, 2019 at 01:48 AM, Rich NE1EE wrote:
because now the phase had a lot of jitter.
this "jitter" is just because phase has noise. The phase is limited to -180 to +180 degree, so when it come to -180, you will see jump to +180. Unwrapped phase will not have such "jitter"
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I think you can use 220 Ah battery (220'000 mAh) and it should works ok
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Re: WINDOZE BASED APPS for the NANO VNA
Hi David,
The .dfu files are used to flah firmware into the? NanoVNA device, you can do that with DFUseDemo software from STI under windows.
Regards
Jos
Op 14-11-2019 om 23:38 schreef David Eckhardt:
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Show quoted text
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. .
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Re: can't find a suitable #battery connector
#battery
Thank you Gyula for the information. I didn't replace any components. I received this complete device with this plug included and without a diode D2. Ok, I'll desolder the connector and will solder the cables directly on the pads. As for the type of diode I found several topics here. Don't know which post to follow. Guess a standard Si diode like 1N4148 should work?
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R?sp.: Re: [nanovna-users] NanoVNA-Saver 0.2.0
I think the frequency of the cross point of those curves is the most important parameter?
Trimis din Yahoo Mail pe Android
Pe vin., nov. 15, 2019 la 0:06, David F4HTQ<f4htq@...> a scris: 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 (¦Ì'r and ¦Ì''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.
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Show quoted text
-----Message d'origine----- De : [email protected] [mailto: [email protected]] De la part de Rune Broberg Envoy¨¦ : 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/¦Ø and X/¦Ø, 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...
:-)
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Re: can't find a suitable #battery connector
#battery
Based on the pictures, the socket soldered to the pcb has a 1.25mm plug and the battery has a 2.54mm plug. I suppose you replaced the power plug with a smaller one so that the D2 diode could be soldered afterwards, but why didn't you solder the D2? D2 is required for newer firmware due to power supply indication. The first versions did not have a power connector, and there is no need to change the battery frequently, so I would cut off the battery connector one by one and solder it to the pcb, as is the case with the first versions.
It is understood that there is a positive pole on the D2 side.
In your area, I would ask the merchant for a refund of approx. 15%, I think that could be realistic. Attach a photo when claiming.
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R?sp.: Re: [nanovna-users] NanoVNA-Saver 0.2.0
HiCan you plese advise the whole procedure and test fixture to identify and characterise unknown ferrite cores with nanovna? ?73 de YO4AUL?
Trimis din Yahoo Mail pe Android
Pe vin., nov. 15, 2019 la 0:06, David F4HTQ<f4htq@...> a scris: 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 (¦Ì'r and ¦Ì''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.
toggle quoted message
Show quoted text
-----Message d'origine----- De : [email protected] [mailto: [email protected]] De la part de Rune Broberg Envoy¨¦ : 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/¦Ø and X/¦Ø, 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...
:-)
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Re: can't find a suitable #battery connector
#battery
just desolder connector and solder wires directly to the pcb. My NanoVNA don't have battery connector at all.
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can't find a suitable #battery connector
#battery
Hi
myy NanoVNA was shipped w/o a battery. Thought that's no problem, opened the back cover and realized that my battery doesn't fit into the connector which is installed on the board. You can see it in the pictures. I also can't find any usable JST jacks for surface mountings in the internet.
Does anyone know where to find a suitable battery with the right plug and right polarity?
73 Carsten DL8AAP
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Re: WINDOZE BASED APPS for the NANO VNA
Dave,
You are very welcome. :-)
--
Rune / 5Q5R
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On Fri, 15 Nov 2019, 01:35 David Eckhardt, <davearea51a@...> wrote: Thanks, Rune. That SW is a downright winner. Thank you!!!!!!!
Dave - W?LEV
On Thu, Nov 14, 2019 at 10:49 PM Rune Broberg <mihtjel@...> wrote:
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
On Thu, 14 Nov 2019 at 23:38, David Eckhardt <davearea51a@...>
wrote:
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
--
*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*
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Re: Performance of 1:1 Balun
Hi Nan
VNA2180 that Steve used have 50 ohm impedance on both ports (A & B). So those formulas will work if vna ports of NanoVNA have 50 ohm impedance. But do they?
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The crossover point between the real and imaginary part of the complex permeability is a good marker on the usable bandwidth or upper application frequency for the ferrite. Obviously the higher perm units have a crossover point well below a few MHz. The lower perm units, say 120, 65, or 40 can extend the crossover to 10 or even 100 MHz. Higher perm, 1500, 2500, etc.... are confined to much lower frequency. You could catalog your VNA measurements for KNOWN curves and then sort your UNKNOWN perm material in than manner. That is what I have done in the past. Then I paint white out on my black ferrite material and mark their perm value with a black Sharpie pen.
Actually obtaining the accurate permeability or for that manner the dielectric K factor for TLine materials is fairly involved and the papers I have seen to extract these values required the complete 2 port S parameters. NIST has a number of papers addressing the measurement technique.
Alan
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Re: Parameter Explanation Please
I am retired and I like to learn new things. I am a ham and l like experimenting with antennas.
I am interested in xfmrs for efhw antennas. I have a VNWA and thought it would be fun to play with the nanovna too, seeing as it only cost $45.00.
I read a lot of Owen Duffy¡¯s articles and like to try out his experiments while learning a bit about rf.
The nanovna uses different terminology than the VNWA but I think I understand the differences.
When my nano arrives I can do comparisons between the two.
Larry
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David F4HTQ wrote:
"finally I do not wait for the weekend :)"
-------------------------------------------------------------------------------------
The test method you described seemed simple enough to give it a quick go. Attached is a photo of the test set-up I used. One turn of wire attached to a Banana-BNC adapter and connected to CH0, hopefully similar to your description.
I pulled out the first ferrite core I could find and measured it. The initial curve from 100k-30M looked like junk below 1M and not enough definition at 30 MHz. I changed the range to 1M -100M. The core is definitely not type 43 and pretty broadband in nature. I measured two other cores just like it and their curves overlapped. Found identifying markings on the cores - Laird type 28B2400-000. Found the curves for Laird 28B on-line and have attached them.
The Laird 28B series is definitely broadband but not sure I could have identified my cores from the Laird curves without priori information. The NanoVNA curves for all three cores did match and I suppose I could build up a signature database and use it to sort unknown ferrites.
Thanks for giving me another idea for using the NanoVNA.
- Herb
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Re: NanoVNA AURSINC v H, Q-0.4.3, images
On Thu, Nov 14, 2019 at 06:48 PM, Dana Whitlow wrote: Results with an S21 measurement of a fairly lossy DUT
Because I am new to all this, I'd need some specifics about that. This thread is comparing what is apparently two VNAs from different Chinese sources. I will pull the case in a few days and compare both internals. Meanwhile, I used the earlier cal, and mounted an MFJ-1714 tele antenna on a tripod at the end of 3.5 m of RG3416. AURS left; H, right. Very similar, I think? I made the mistake of not setting the AURS marker on 146 MHz, as I did for the H.. -- 73 de Rich NE1EE On the banks of the Piscataqua
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Re: Replacement Power switch
Check out e-Pay. You can get 50 pcs for $1.25 AND free shipping. 73, Dick, W1KSZ ________________________________ From: [email protected] < [email protected]> on behalf of Bob Albert via Groups.Io <bob91343@...> Sent: Thursday, November 14, 2019 5:34 PM To: [email protected] < [email protected]> Subject: Re: [nanovna-users] Replacement Power switch 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 On Thursday, November 14, 2019, 03:04:26 PM PST, Herman De Dauw <on1bes@...> wrote: 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
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Re: Replacement Power switch
As Herman said, they can be had on eBay
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finally I do not wait for the weekend :)
This is the curve for 61
( one turn of emailled wire on BN61-202)
There is the corresponding curve on manufacturer website
And finaly for the 73
( one turn of emailled wire on BN73-202)
and the manufacturer curve:
David.
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-----Message d'origine----- De : [email protected] [mailto: [email protected]] De la part de David F4HTQ Envoy¨¦ : vendredi 15 novembre 2019 01:04 ? : [email protected]Objet : Re: [nanovna-users] NanoVNA-Saver 0.2.0 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. -----Message d'origine----- De : [email protected] [mailto: [email protected]] De la part de hwalker Envoy¨¦ : vendredi 15 novembre 2019 00:38 ? : [email protected] Objet : Re: [nanovna-users] NanoVNA-Saver 0.2.0 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
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DL8AAP Carsten
Gyula Molnar
Rich NE1EE
Dick
chuckt