Is the USB cable faulty? Try replacing the USB typeC cable.
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Re: Analysing Input Impedance Matching Circuit for the NE602
Kerr,
I was curious to see what would happen if the turns count was reduced to 7 from 8. The results were better with an improvement in S11 and S21. I have attached some plots showing the difference. I then made measurements with a 3.26k resistor on the secondary which is an approximation to the impedance of your NE602 in balanced mode.
Regards - Roger
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Moderated
Re: Another off-topic about Smith chart
OP: For technical topics, Wikipedia is actually pretty good. Case in point, I think this link directly answers your question.
TLDR, it's a Mobius transformation. That's kinda cool! Maybe it was mentioned, but I don't remember that description in six+ years of University. (BS+MS in USA)
No matter if you learned the Smith Chart on a computer last week, or you derived it in crayon in kindergarten, I think with both the impedance and admittance plots in red and green it's an awesome Christmas decoration.
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Re: NanoVNA-V2 from Tindie - First impressions
Hello and thanks for your update.
Could you please share some more photos and details of the V2?
Waiting for it also.
And nanovna-saver will be updated to make it compatible with the V2, once
the developer has his own unit and time :)
All the best!
*73 de Luís, CT2FZI*
*QRV @ 145.300 MHz | **CQ0VMST (VHF REP Monsanto)*
<>
<>
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On Thu, 26 Mar 2020 at 20:24, Wolfgang Kiefer <woki@...> wrote: Today the parcel has arrived. Connected to a PC (Micro USB plug), it runs
without problems.
A 50 Ohm load connected, tested the frequency limit: very impressed - 4.5
GHz are displayable. Good results until 3.5 GHz.
New functions: maximum and minimum search of the cursor. Screef flip
(rotates 180 degrees). Three dip switches instead of the jog. (Very small.)
Unfortunately the NanoVNA- Saver does not connect to the new device. But
there is another solution (see the pictures). It is called VNA_QT.exe.
My resumee: For about 60 � a very good deal!
Wolfgang Kiefer
DH1AKF
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I received the H4 a few days ago.
I played with it in a "stand alone" configuration (not connected to the PC) and it worked very well.
than I connected it to my PC to charge the battery and did not noticed that the PC was loading a driver...and disconnected it!
PC gave the alarm that the driver was not succesfully loaded.
I connecte the H4 again and checked the device manager: actually a driver "STMsomething" was there...but not operational.
I tried to reinstall it looking both in my PC and than in the net, but no way to find a good one.
so I deleted the driver, switched off the H4 and rebooted the PC to start again.
but when I reconnected the H4 I got the "error 43" message: unknown device.
no way to make the PC recognize the H4.
OS. win7 home
H4: firmware 4.0.5-7 -g57d62f2 built time:01.01.2020.
I also connected the H4 to another PC running win10PRO with the same result: "error 43"...
I am a little desperate!
best 73
de
i2NDT Claudio
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Re: NanoVNA-V2 from Tindie - First impressions
hallo Liber Wolfgang, wie gehts dir.....
60� mit versand? alles ?
danke!
Em qui., 26 de mar. de 2020 às 21:24, Wolfgang Kiefer <woki@...>
escreveu:
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Show quoted text
Today the parcel has arrived. Connected to a PC (Micro USB plug), it runs
without problems.
A 50 Ohm load connected, tested the frequency limit: very impressed - 4.5
GHz are displayable. Good results until 3.5 GHz.
New functions: maximum and minimum search of the cursor. Screef flip
(rotates 180 degrees). Three dip switches instead of the jog. (Very small.)
Unfortunately the NanoVNA- Saver does not connect to the new device. But
there is another solution (see the pictures). It is called VNA_QT.exe.
My resumee: For about 60 � a very good deal!
Wolfgang Kiefer
DH1AKF
|
Re: NanoVNA-V2 from Tindie - First impressions
Today the parcel has arrived. Connected to a PC (Micro USB plug), it runs without problems.
A 50 Ohm load connected, tested the frequency limit: very impressed - 4.5 GHz are displayable. Good results until 3.5 GHz.
New functions: maximum and minimum search of the cursor. Screef flip (rotates 180 degrees). Three dip switches instead of the jog. (Very small.)
Unfortunately the NanoVNA- Saver does not connect to the new device. But there is another solution (see the pictures). It is called VNA_QT.exe.
My resumee: For about 60 � a very good deal!
Wolfgang Kiefer
DH1AKF
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S-parameters versus Time.
Hello Users,
Is there a possibility to performance measurement S-parameters versus Time,
to a fix frequency?
Are there anyone Who has been working or know how to measurement Recovery
Time using NanoVNA
Thanks a lot and comments are welcome!!!
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Hello, and thanks for the suggestion. I was able to successfully complete the install after rebooting my computer. Apparently there was a Windows update that had installed, and it required a reboot to complete its installation. Once I rebooted, I was able to install the DfuSe_Demo software and use it to update the firmware on the NanoVNA.
Thanks again for your input.
Jim
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Hola Ignacio,
Es solo un mensaje de "firma" agregado automáticamente después de cualquier texto (arriba) que no tiene nada que ver con el tema en discusión ...
Por favor ignora jaja
@Eric@ he was mentioning the KD4HNX email signature. Please ignore :)
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Have you tried disabling AntiVirus/Protection utilities prior to running the updater?
Would suggest disconnecting network prior to disablement.
Cheers
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At 07:22 PM 3/25/2020, James Bolm wrote:
I received a NanoVNA-H, firmware version 0.4.5-1-gfbbceca, Build Time: Dec
26 2019 - 19:32:31 today.? Finding that there is new firmware, I read the
WIKI and downloaded STSW_STM32080 from the ST website to facilitate the
firmware upgrade.? When I run DfuSe_Demo_V3.0.6_Setup.exe, it leads me
through a few screens to enter my name, and then start the install.? It
immediately returns a screen with the message that "The wizard was
interrupted before DfuSe V3.0.6 could be completely installed. Your system
has not been modified. To complete installation at another time, please
run setup again."? I am running the setup program as an administrator, and
have tried running it from the command line, also as administrator, again
with no success.
Has anyone else had this problem, and if so, have you found a resolution?
Thank you,
Jim
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Sincere apologies for something I must have done wrong. Please help me to understand how I should have explained the problem is most prominent at higher frequencies, much more then the 0.1 ohm differences at DC. -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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You say that because you never lived under a military dictatorship.
These political comments (included mine) should be avoided, they are not good for the good health of the group.
Ignacio, EB4APL
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El 26/03/2020 a las 11:31, Dallas KD4HNX via Groups.Io escribió: That's not what my calculator says...
4.2 circuit:91 ohms in parallel with 51+11+51
take 1/91 + 1/113 = 1/x and that comes to 50.4068 ohms...
When I do that to circuit 4.2.1 I come up with 50.64 ohms...
73 Dallas, KD4HNX
Whatever you do, don’t fall victim to?“paralysis by
analysis.” Go ahead and buy/build one and start
tinkering with it. This is a learn by doing hobby.
No politician or scholar assured your freedoms.
A Soldier, Sailor, Marine, or Airman did!
--
El software de antivirus Avast ha analizado este correo electrónico en busca de virus.
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Did you do a calculation over the total frequency range or only DC? The impedance mismatch was most prominent at higher frequencies due to SA602 input capacitance. Increasing R22 and R23 reduced this problem. -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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ASSUMING the SA602 inputs are 1.5K each for a total of 3K my calculations come up with changing the 11 ohm 1% resistor with a 13.2 ohm 1% resistor from Digi-Key...??
1 over 1/3000 + 1/91 + 1/115.2 = 49.992 ohms
Only one part needs to be changed vs swapping out all 4...
The 4.2.1 ckt math would be:
1 over?1/3000 + 1/56 + 1/529.9 = 49.806 ohms
73 Dallas, KD4HNX
Whatever you do, don’t fall victim to?“paralysis by
analysis.” Go ahead and buy/build one and start?
tinkering with it. This is a learn by doing hobby.
No politician or scholar assured your freedoms.
A Soldier, Sailor, Marine, or Airman did!
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On Thursday, March 26, 2020, 07:58:21 AM EDT, erik@... <erik@...> wrote: 4.2.1 is better because the input impedance of the SA602 (1.5kOhm//3pF per input) has less impact compared to 4.2 -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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Moderated
Re: Another off-topic about Smith chart
I meant "there is not a good subsitute"
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El 26/03/2020 a las 14:00, EB4APL via Groups.Io escribió: If you pay attention, the Smith Chart display on the nanoVNA lacks all units on its axes. This is because this display is intended to see where the impedances are. For measuring, instead of read it on the graph, such in the old times, you use the markers which give you accurate results.
For RF designers used to see the results in a Smith Chart, it is invaluable. You have to learn to interpret it, but here are not a good substitution.
Regards,
Ignacio, EB4APL
El 25/03/2020 a las 20:10, pez@arg escribió:
Smith Chart : In this computer era, this extremely high-effort demanding,
highly-inaccurate, old-time graphics tool became completely obsolete,
because it is a totally useless one in every other aspect except that one
of "just take-a-look demo" - or of fancy impression making to unsuspected,
innocent, inexperienced beginners, of course
--
El software de antivirus Avast ha analizado este correo electrónico en busca de virus.
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Thank you Helmut and Ignacio for the speedy replies.
Helmut, I am running Windows 10 Home with all recent updates. I had thought about the permissions issue before posting, but was unable to find a place in the install dialog to change the install directory.
Ignacio, Per the documentation for STSW_STM32080, it contains the necessary Windows driver.
At any rate, I think that I resolved my problem. It appears that my system had automatically installed some updates, and was waiting for a reboot to complete the installation. I rebooted my system, after which the DfuSe_Demo installed without any problems.
Thank you again for your inputs.
Jim
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Moderated
Re: Another off-topic about Smith chart
If you pay attention, the Smith Chart display on the nanoVNA lacks all units on its axes. This is because this display is intended to see where the impedances are. For measuring, instead of read it on the graph, such in the old times, you use the markers which give you accurate results.
For RF designers used to see the results in a Smith Chart, it is invaluable. You have to learn to interpret it, but here are not a good substitution.
Regards,
Ignacio, EB4APL
toggle quoted message
Show quoted text
El 25/03/2020 a las 20:10, pez@arg escribió: Smith Chart : In this computer era, this extremely high-effort demanding,
highly-inaccurate, old-time graphics tool became completely obsolete,
because it is a totally useless one in every other aspect except that one
of "just take-a-look demo" - or of fancy impression making to unsuspected,
innocent, inexperienced beginners, of course
--
El software de antivirus Avast ha analizado este correo electrónico en busca de virus.
|
Moderated
Re: Another off-topic about Smith chart
I am not sure if "reply " is attached to post or thread so..
To Alan Victor ,
OM - would it be possible / appropriate to discuss details of actual C code (OpenGL) implementation in private ?
I am no math wiz, and I am having issues writing the code for imaginary "axis" and I feel the discussion here is heading different direction(s).
BTW your article actually includes "formulas" for drawing the cart, very nice and unexpected benefit. Thanks
73 AA7EJ Vaclav
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Moderated
Re: Another off-topic about Smith chart
On Wed, Mar 25, 2020 at 03:10 PM, pez@arg wrote:
Smith Chart : In this computer era, this extremely high-effort demanding,
highly-inaccurate, old-time graphics tool became completely obsolete,
because it is a totally useless one in every other aspect except that one
of "just take-a-look demo" - or of fancy impression making to unsuspected,
innocent, inexperienced beginners, of course
And like the current and maybe past few generations who grew up doing math on calculators, they can't even add and subtract without them. When the power goes poof, their tools are gone and they're helpless. Use the fancy programs once you learn the basics behind them. And then maybe you can develop a fancy program, too. BruceN / K4TQL -- *"To invent, you need a good imagination and a pile of junk"* -- Thomas Alva Edison (1847-1931)
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Roger Need
CT2FZI
Wolfgang Kiefer
James Bolm
Dallas N4DDM