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I was also going to suggest you actually measure the εr of the PCB you
actually used at the frequency you intend to use it. The εr of FR-4 board
falls between an upper an lower limit, but it is not controlled. If you
want something more controlled and predictable, use RT/Duroid, but it is
expensive. Also, Teflon board is also better controlled than FR-4, but
also expensive. Both are far better substrates for microwave applications.

Dave - W?LEV

On Thu, Sep 1, 2022 at 10:31 AM Diane BONKOUNGOU <dianebonk2@...>
wrote:

Hello everyone,
I used OpenEMS software for my simulation and I got simulation results
that are very different from my experimental result, I have a PCB antenna
whose resonant frequency is around 2.4GHz. I design the same thing on
OpenEMS but the simulation gives me a resonant frequency of around 2.66GHz.
Such a difference of 0.2GHz is important in RF, isn't it? Knowing that the
frequency range of Bluetooth Low Energy is 2.4-2.5GHz.
I have calibrated very well my NanoVNA and my experiment result must be
good. I know that because I tested the Texas instrument PCB IFA antenna and
I get the same result as in their Datasheet.
Can you recommend a free tool for antenna simulation?
I have searched but I can only find OpenEMS based on the FDTD method. The
others are professional and paid tools for PCB trace antenna simulation.
Best regards.

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


--
Dave - W?LEV

You may have forgotten that you can put an extension cord of the length you want between the nanaoVNA box and the location where you are going to do the calibration. Even the imperfections of the extension will be compensated by the calibration. I did a test with a 93 Ω cable.

Take advantage of this extension to change the type of connector. Switch to a female BNC socket for example, firmly fixed on a support. SMA are too fragile to be screwed and unscrewed too often.
--
F1AMM Fran?ois

De la part de n1evh via
Envoyé : jeudi 1 septembre 2022 16:10

Hi Zack?The big inventory is Arlon 25N which is also space qualified!Currently have 6 antenna assemblies in orbit and working on 3 more!I do a lot of antennas were the Er of the PCB material is not that important, like Vivaldi, LP, and Planar Disk antennas.? ?Also putting the antenna on VERY thin material makes the Er less important.? i.e. .008" multi-layer material normally used for the interlayers in multilayer PCB's.? KentPS? The Nano's are cute, I've got 3.? (Different work areas).

Kent Britain WA5VJB may chime in, but he found the variation in dielectric
constant for various samples of G10/FR4 so large that he bought a large
stock of board with the same dielectric constant and makes his pc board
antennas from that. Using a piece of G10 or FR4 at random may not produce
the expected results.

Zack W9SZ

On Thu, Sep 1, 2022 at 7:59 AM Brian Howie GM4DIJ <brian@...>
wrote:

On 01/09/2022 11:31, Diane BONKOUNGOU wrote:

Hello everyone,
I used OpenEMS software for my simulation and I got simulation results

that are very different from my experimental result, I have a PCB antenna
whose resonant frequency is around 2.4GHz. I design the same thing on
OpenEMS but the simulation gives me a resonant frequency of around 2.66GHz.
Such a difference of 0.2GHz is important in RF, isn't it? Knowing that the
frequency range of Bluetooth Low Energy is 2.4-2.5GHz.

I have calibrated very well my NanoVNA and my experiment result must be

good. I know that because I tested the Texas instrument PCB IFA antenna and
I get the same result as in their Datasheet.

Can you recommend a free tool for antenna simulation?
I have searched but I can only find OpenEMS based on the FDTD method.

The others are professional and paid tools for PCB trace antenna simulation.

Best regards.

Can you upload the file and I'll have a look The dielectric constant you
chose might differ from the real one depending on the material. There
are also issues in getting the mesh riggt.


I have a couple of PCB antennas for 1.3, 2.3 and 3.4GHz which are ok on
the nanoVNA , I was planning to model. them . They seem to have a
stripline matching section which might be tricky to model accurately.

Brian


--
Brian

I recently purchased a NanoVNA (with a 2.8 inch screen). I was
wondering if anyone has designed/printed a stand for the
NanoVNA???

I'm looking for something that I can put the end of it into (so that
the SMA jacks are facing up) so I can attach an SMA antenna
for an HT to it.

With a stand... I won't have to worry about the NanoVNA falling
over if the USB cable between my laptop or tablet gets hit or
moves (more of a problem if holding a tablet) and since it will
keep the NanoVNA from falling over... I won't have worry about
anything touching the antenna to affect the measurements.

Thanks,

Mike - N1EVH

On 9/1/22 6:21 AM, Gary W9TD wrote:

EZNEC is now free.

EZNEC as a Method of Moments code that is derived from NEC is really a "wire" modeling code and doesn't do patches very well.

One can "grid" a patch, and put it over ground with soil properties set to match the substrate, but it doesn't have a way to do the ground plane on the other side of the substrate. (well, in NEC4 you could bury a grid of wires)).

NEC based codes will not do the matching sections or transmission line.


What the OP needs is a low cost tool that is designed for microstrip patches.

Ancient, but maybe PUFF (an early microwave circuit modeling package) would work?

At work we use HFSS, but that's sort of the antithesis of free.

I'd start with the list here:



Sonnet has a student version

Hi Brian,
Thanks for your reply, attached is my code. I put the dielectric at 4.8
it's FR4. I started with 4.29, my PCB was made by PCBway company. I remark
that when I increase permittivity the frequency decrease.
I also try to put a thickness to my copper traces, I finally forgot this
Idea.
After I changed the metal trace with the copper having losses. *%CSX =
AddMetal( CSX, 'ifa' );* change this with the second line

*CSX = AddConductingSheet( CSX, 'ifa', 59e6,
70e-6); %* 59 copper conductivity, 70e-6 is the losses
Also, I try to put a layer of copper in the PCB because it is a 4-layer PCB
and it gives me 2.66GHz, otherwise, I have 2.8GHz.
My PCB is 0.8mm thicker, with 4 layers of elements. And yes, you are right,
the mesh size can be a big factor. I spend a lot of time on the mesh part.
I tried using Detect edge but I get errors all the time. I ended up doing
the meshing by hand.
-I also check the simulation box position my PCB is inside, but I am
wondering if the position is good.
Best regards

Le jeu. 1 sept. 2022 à 13:59, Brian Howie GM4DIJ <brian@...> a
écrit :

Yes, and I have known Roy for nearly 30 years, but EZNEC does not do PCB antennas.? ? ?When you download his Pro version, be sure to get the manual as well.? He has RETIRED!? ?Kent

What Er did you use for the PCB Material?Unless it is very expensive material where the plot the Er by frequency, you really don't know the Er.
It is industry standard to measure the Er at 1 kHz.Typically they list the Er for fiberglass PCB material.(Yea, the call it FR4, but you have not been able to buy real FR4 for the last 10 years.? The spec for FR4 calls for a Bromide anti-flammability that has been banned)Er is listed as 4.4, but as you go up in frequency Er drops.? At 2.4 GHz it is typically in the 3.8-3.9 range.? ? Personal experience in making thousands of 2.4 GHz patch antennas.? Kent WA5VJB

Next try on (electrical) - this time with focus on use in university education - ref is a paper of ASEE (American Society of Engineer Education).
From this point we can increase carefully.

EZNEC is now free.

On 01/09/2022 11:31, Diane BONKOUNGOU wrote:

Hello everyone,
I used OpenEMS software for my simulation and I got simulation results that are very different from my experimental result, I have a PCB antenna whose resonant frequency is around 2.4GHz. I design the same thing on OpenEMS but the simulation gives me a resonant frequency of around 2.66GHz. Such a difference of 0.2GHz is important in RF, isn't it? Knowing that the frequency range of Bluetooth Low Energy is 2.4-2.5GHz.
I have calibrated very well my NanoVNA and my experiment result must be good. I know that because I tested the Texas instrument PCB IFA antenna and I get the same result as in their Datasheet.
Can you recommend a free tool for antenna simulation?
I have searched but I can only find OpenEMS based on the FDTD method. The others are professional and paid tools for PCB trace antenna simulation.
Best regards.

Can you upload the file and I'll have a look The dielectric constant you chose might differ from the real one depending on the material. There are also issues in getting the mesh riggt.


I have a couple of PCB antennas for 1.3, 2.3 and 3.4GHz which are ok on the nanoVNA , I was planning to model. them . They seem to have a stripline matching section which might be tricky to model accurately.

Brian


--
Brian

Hello everyone,
I used OpenEMS software for my simulation and I got simulation results that are very different from my experimental result, I have a PCB antenna whose resonant frequency is around 2.4GHz. I design the same thing on OpenEMS but the simulation gives me a resonant frequency of around 2.66GHz. Such a difference of 0.2GHz is important in RF, isn't it? Knowing that the frequency range of Bluetooth Low Energy is 2.4-2.5GHz.
I have calibrated very well my NanoVNA and my experiment result must be good. I know that because I tested the Texas instrument PCB IFA antenna and I get the same result as in their Datasheet.
Can you recommend a free tool for antenna simulation?
I have searched but I can only find OpenEMS based on the FDTD method. The others are professional and paid tools for PCB trace antenna simulation.
Best regards.

I moved from Windows XP Pro 32 bit to Windows 10 64 bit, starting october last year.

It was definitely not a painless transition. I installed W10 on a new computer, and had to run with both in parallel for three months, while slowly learning to tame that crazy overactive beast W10 is, moving over my software, data, and part of the hardware, and search for replacements for many programs that would not run on W10. Only around Christmas I could finally stop using the old computer.

But it was not possible to transfer everything to W10. In the end I installed a virtual machine with Win XP 32 bit on the W10 system, and I have to use that to do some tasks. For example, everything related to my Garmin GPS requires the old Windows, because neither Garmin nor anyone else ever released 64 bit drivers for the line of older GPS receivers.

And I had to replace many programs by different ones. For example, AutoCAD. Of course modern AutoCAD works on W10,but is way too expensive, and the old version I had will definitely NOT run on W10. So, NanoCAD to the rescue. Same thing with many other programs.

And some features, even hardware, simply went to waste. Instead of my excellent old Soundblaster Audigy with the kX-Project driver, now I'm stuck with a crummy integrated audio "solution" that only offers basic functionality and gets digital interference. Instead of five RS-232 ports now I have just one, and so on.

I gained access to modern software, but lost access to old and very useful software and hardware. So I can very well understand the reluctancy to "upgrade" to W10. The backward compatibility problems are obvious and severe. For me the trigger to move away from Win XP was that all current web browsers no longer supported XP, and that many modern websites don't run in older browsers. I got locked out of many web services that I really need. And moving to Win 7 as an interim step would only have delayed the inevitable. But for somebody who currently is using Win7, the most sensible thing to do is to stay in Win7 as long as circumstances allow.

About virtual machines: It's important to know that one can easily run a 32 bit virtual machine on a 64 bit real machine and OS, and what's far less known, it's also possible to run a 64 bit virtual machine on a 32 bit main operarting system! That's what I was doing to run some modern software, before switching to W10. The limit is given by RAM: 32-bit Windows only handles somewhat more than 3GB, so a virtual machine running in 32 bit Windows can hardly get more than 2GB or so of RAM, and that's very limiting in a 64 bit virtual machine.

I have no trouble using the NanoVNA on W10, through NanoVNA App, but I haven't tried yet updating its firmware from the new system. The last update was done using my old Windows XP computer. I will handle that like I have been handling all other transition problems: When I need to do something, I just try if it works, and if it doesn't, I start looking for solutions, drivers, newer software, tricks, etc..

Hi Roger,

Mine is marked HW version 4.3 MS on the back. I used NanoVNA-H4-MS_20220831.dfu from Hugen's github page.

Thought that was the version that was on it when I got it since the description on Amazon said updated 2022 version. Glad I installed the 'wrong' one, LOL!

Really appreciate your help!! Maybe if I had mention I had the MS version it would have been easier to fix the issue.

Thanks!!!!

Please PM me.

On Wed, Aug 31, 2022 at 12:39 PM Randy <wrmoore47@...> wrote:

NanoVNA-H4 for sale. Bought from R&L Electronics 4/2020. Used a couple of
times back then and not since. Contains all original cables/connectors/cal
loads/etc. In original, nice box. Just powered it up and charged the
battery and it seems to be working fine. Version v.0.5.0. I haven't
followed this device on-line, so don't know what the current version is. No
manual or instructions were included, but lots of info on this group and on
YouTube. $50 including shipping in US. PayPal preferred. If you need more
pix or have questions, just ask.

Tnx es73,
Randy, KS4L





--

HOGALLEN aka
Gary A. Smith
2150 East 575 North
St. George Utah 84790
435 272-7077

On Wed, Aug 31, 2022 at 12:39 PM Randy <wrmoore47@...> wrote:

NanoVNA-H4 for sale. Bought from R&L Electronics 4/2020. Used a couple of
times back then and not since. Contains all original cables/connectors/cal
loads/etc. In original, nice box. Just powered it up and charged the
battery and it seems to be working fine. Version v.0.5.0. I haven't
followed this device on-line, so don't know what the current version is. No
manual or instructions were included, but lots of info on this group and on
YouTube. $50 including shipping in US. PayPal preferred. If you need more
pix or have questions, just ask.

Tnx es73,
Randy, KS4L





--

HOGALLEN aka
Gary A. Smith
2150 East 575 North
St. George Utah 84790
435 272-7077

NanoVNA-H4 for sale. Bought from R&L Electronics 4/2020. Used a couple of times back then and not since. Contains all original cables/connectors/cal loads/etc. In original, nice box. Just powered it up and charged the battery and it seems to be working fine. Version v.0.5.0. I haven't followed this device on-line, so don't know what the current version is. No manual or instructions were included, but lots of info on this group and on YouTube. $50 including shipping in US. PayPal preferred. If you need more pix or have questions, just ask.

Tnx es73,
Randy, KS4L

You haven't done it but I think your page can interest a lot of people


--
Fran?ois

On Wed, Aug 31, 2022 at 05:40 AM, TE Dukes wrote:

Got it working !!!

I had decided to send this back to Amazon and try another in case I may have
gotten a bad one.

I flashed the 'original' Hugen FW back but must have used a newer version by
mistake. Everything is working and I can do more than 101p.

Glad you got it working. A few questions.

1. What Hugen version are you running now?
2. Did you use the NanoVNA-H4-MS or NanoVNA-H4-SI version? The SI version is for the original clock chip which is hard to get now. The MS version is for the Chinese clone clock chip which Hugen is using in recent production.
There is a label on the back of Hugen's H4 which has an M for the Chinese version clock chip.

Roger

Roger