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Re: Just got mine. Looking it over.
Hi Gyula,
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you're right, the software works fine without 64 bit hardware. The downloadable executable from GitHub also works with Windows 7 32 bit. However, PyQt5 is not available from pip for 32 bit Linux, so any 32 bit Linux users would have to install and compile this manually. -- Rune / 5Q5R On Wed, 16 Oct 2019 at 10:06, Gyula Molnar <gyula.ha3hz@...> wrote:
Hi, |
Re: Just got mine. Looking it over.
Hi,
I have Python 3.7.4 installed on win7-32 bit SP1 integrated, which runs the nanovna saver. Of course, the required modules are installed with the -pip command, and I have verified that they are present. I don't think 64-bit hardware is needed to get it running. 73, Gyula HA3HZ |
Re: Am I Fixing my BNC Calibration using Calibration Standards Adjustments in nanoVNA-Saver 0.1.2
Hi Bryan,
thank you very much! :D I'll sit down this evening and read through your explanation more thoroughly than this morning's coffee break allows. But I will comment briefly on the crashes: If you want, it would be helpful for me if you were to launch the application from a command prompt (or terminal window if on Linux), preferably using the "-d" parameter to enable debugging output. After the crash, the final error message should then be preserved in that window. This will show me exactly where in the code the crash occurred. When it comes to calibration, I have a decent idea. It won't be fixed in 0.1.3, due out Soon<tm>, but I promise I'll make better input validation for those fields for 0.1.4 ;-) For now: Never leave them empty, never set C0 to 0, and never feed them after midnight. PS. I swapped F and H in the calibration window, and *noone noticed* until now?! Quite how I made that mistake I don't know. :-) -- Rune / 5Q5R On Wed, 16 Oct 2019 at 07:10, bryburns via Groups.Io <bryburns= [email protected]> wrote: On Tue, Oct 15, 2019 at 03:42 PM, Rune Broberg wrote:it |
Re: SOLT calibration vs. TRL
On Tue, Oct 15, 2019 at 03:59 PM, Dr. David Kirkby from Kirkby Microwave Ltd wrote:
The nanoVNA is a full three mixer three receiver VNA without the switch to reverse the signal path |
Re: Just got mine. Looking it over.
Hi Paul,
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great to hear that it runs on Fedora :D Thanks for trying out the software, and for helping other users get it running as well! -- Rune / 5Q5R On Wed, 16 Oct 2019 at 04:08, Paul Alfille <paul.alfille@...> wrote:
Ahh the linux holy wars. I can assure you that nanovna-saver works fine on |
Re: Am I Fixing my BNC Calibration using Calibration Standards Adjustments in nanoVNA-Saver 0.1.2
Dr. David Kirkby from Kirkby Microwave Ltd
On Wed, 16 Oct 2019 at 06:10, bryburns via Groups.Io <bryburns=
[email protected]> wrote: On Tue, Oct 15, 2019 at 03:42 PM, Rune Broberg wrote:. An interesting post Bryan. I agree that the resistance of the short is unlikely to be an issue, but the resistance will increase with frequency due to the skin effect. To measure low resistance values one needs to use 4-wire Kelvin connectors. But even without a meter with that facility, it is very easy to use a constant current source and a decent handheld multimeter. Many cheap handheld multimeters can read 100 uV easily. Pass 100 mA thru the DUT and you a 1 milli ohm resolution. Dave. --Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: Another ebay deal?
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 15 Oct 2019 at 00:09, Oristo <ormpoa@...> wrote:
Do you have any gnuplot code which can import a Touchstone file and plotit on the Smith Chart? You are obviously a much more competent gnuplot user than me. I like it the fact that I can use it non-interactively. The calibration kits I sell come with about 10 graphs showing various plots such as the properties of calibration standards, the verification attenuator etc. Manually plotting that lot would be extremely time consuming and error prone, but being able to generate all the PDF plots from a single unix shell script makes the process much easier. --Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: Am I Fixing my BNC Calibration using Calibration Standards Adjustments in nanoVNA-Saver 0.1.2
On Tue, Oct 15, 2019 at 03:42 PM, Rune Broberg wrote:
Rune, Yes, your software can do a lot of things that I seem to need. Thanks, again, for continuing to work on this effort. You and your efforts are greatly appreciated. I will cover the changes in the open, short, and load separately below. To get the plots shown here, I averaged 3 (or more) copies of 5 scans from 50 kHz to 900 MHz. The total number of frequency samples was therefore 505 samples or about every 1.78 MHz. Averaging is very useful and important in nanoVNASaver, especially when looking at these kinds of measurements, especially above 300 MHz. First I'll talk about the open. On the Smith chart plot little change is observable after the tuning is applied because the changes being made represent small changes in the phase of S11. In fact, to see the changes one has to look at the phase of S11 on a scale of about +/- 2 degrees. The S11 phase of the open is shown in the file "S11-Open-Phase-NoTuning.png". The change is such a small change in the phase, it is almost impossible to see anything on the Smith chart. The data is all clustered near the right side of the Smith Chart as it should be after an effective calibration. However, it appears to me there is real data in this phase plot, even after calibration but before applying any tuning to the parameters in the "Calibration standards" form. When I changed C0 in the "Calibration standards" form of nanoVNA-Saver to 1200 and the offset delay to -55 ps. This change produced the phase plot in the file "S11-Open-Phase-with-Tuning.png". Notice two things about the plot after tuning. 1) There is no "quadratic looking" drop in the phase as we move from low frequencies to higher frequencies as there was before tuning. 2) Although I did not do this, a linear fit to the data in the phase plot after tuning will be a horizontal line near zero degrees. This is the definition of an ideal open. Thus, while you cannot readily see such a small change on a Smith chart, there is some significance to the changes because we removed frequency dependent artifacts of the open I used in the calibration process. Please also notice from the amplitude charts in the first post in this series show some improvement in the trend of S11 in dB when measuring the open RG-213 cable. This is not very compelling, but read on. Now let's talk about the short. The short I used produced a nice dot on the left side of the Smith Chart after the normal calibration; however, there was significant ripple remaining in the S11 amplitude as shown in the plot below "RG-213-WithOpenOnlyTuning.png" I suspected, but did not know that could be the fault of the inductance in the short that was used in the calibration. By modifying the L0 parameter in the "Calibrations standards" form we can remove the inductance that may be present in the short I used. The resulting S11 amplitude plot is attached to the first post above and called "S11-RG213-WithCalTuning.png". Also, please refer to my post to Kurt in this thread that shows the vastly improved Smith chart for the RG-213 cable. The circles are now circles and they are much more closely centered on 50 ohms. So, now to your question: What does the actual short used in the original calibration look like on the Smith chart once the L0 correction for the Short is inserted? The result is shown in the figure "Smith-OriginalShort-WithCorrections.png". This result should be exactly like a 1.2 nH inductor which is what I tried to remove using the L0 term. In fact, nanoVNA-Saver confirms this inductance after this correction is applied by indicating 1.2 nH is the "parallel X" when measuring the actual short. When the VNA is properly calibrated for a short, it shows the actual inductance of the physical device I used, equivalent to 1.2 nH. In the case of my BNC short, I don't think I have the ability to reliably measure a resistance that small. The ohmmeter I have won't go lower than 0.05 ohms even when shorting the test leads together. When measuring the short I used, it still measures 0.05 ohms. I doubt that many folks doing hobbyist work can measure the resistance of their short either. Such small resistance values have little impact in a 50 ohm system. Therefore, I don't think there is benefit to including a resistor as a part of the cal correction for a short. A discussion of the load follows. I won't go into the details about the tuning I did for the load. A similar procedure to what was used for the open was used for the load. Here, again, averaging a lot of sweeps is important in order to measure the trends in the phase of a signal with a return loss of some 40 to 50 dB. In order to flatten the S11 phase of the termination I used for calibration I did need to add a very small amount of inductance (50 e-12) in the calibration form. This is the equivalent of trying to remove 0.05 nH, a small amount indeed. At 900 MHz that is a reactance of about 0.28 ohms. Certainly not huge in a 50 ohm system. Of course, this small change is unobservable on a Smith chart using the nanoVNA but it is clearly visible on the S11 phase plot. Long papers have been written on all of the possible issues with trying to model various loads and what to do to compensate for various types of loads at various frequencies. I think there are too many topologies to deal with in this type of software. The capacitance can be in series with the 50 ohm resistor or it can be in parallel or there might be capacitance in series and in parallel.... The same can be said of the inductance. In my opinion, you could leave what you have in place and let folks work with it so long as you allow negative numbers everywhere. Then folks can think about things in whatever way they must as long as you are clear about what you are doing in the software with the non-ideal values entered in the various boxes of the "Calibration standards" box. By-the-way - When I reset some of the values in the Calibration standards box to zero after putting in and applying values, nanoVNA-Saver 0.1.2 immediately crashes. You might want to look into this. I am sure it is reproducible. Right now, I don't recall which ones do it. I hope this helps answer your questions. Again, thank you Rune for making the nanoVNA-Saver software available. I find it particularly valuable and useful. -- Bryan, WA5VAH ![]()
S11-Open-Phase-NoTuning.png
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S11-Open-Phase-with-Tuning.png
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S11-RG213-WithOpenOnlyTuning.png
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Smith-OriginalShort-WithCorrections.png
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Re: Can't update firmware
Thanks, Larry. I've tried these steps many times with no success.
Let me trace the path I've been taking and see if you can spot where I'm going wrong. I followed your pointer to GenHu site Read through his instructions titled Upgrade NanoVNA use DFU.pdf Clicked on my desired .dfu, and download the file NanoVNA-H_AA_20191009.dfu, which I stored in the same folder as DfuSeDemo.exe. Connected NanoVNA to Windows 10 USB port and started up NanoVNA in programming mode. This generates a new directory named Universal Serial Bus devices, and it contains a driver named STM32 BOOTLOADER I've seen screen shots of successful firmware updates, and they show this new file to be in the Universal Serial Bus controllers directory, and the driver is named STM Device in DFU Mode. If I could get past this driver problem then I think the rest would fall into place. |
Digi-Key part numbers for various SMA adapter bits
In case nobody has made this public, below find some part numbers for useful or absolutely required fittings and adapters.
A couple of each are en route to me right now. (From Digi-Key. Not Mouser. I gave up on Mouser after three orders in a row were screwed up, costing me serious coinage and time lost for five different jobs.) Digi-Key part numbers: ACX1242-ND SMA Jack-Jack (like the one shipped with most NanoVNAs) ACX1240-ND SMA Plug-Plug (exactly the opposite polarity of the 1242 above. Might be handy setting up a DUT, you never know...) ACX1246-ND SMA gender - mender. This is a male to female converter J10097-ND SMA to BNC converter. Most of my stuff is UHF connectors, SO-239 / PL-259, but I already have adapters for BNC for that. Digi-Key (and likely Mouser, if you prefer them - I don't have a dog in this hunt so get it where you like) has roughly a thousand different SMA to --something-- adapters and fittings. (The SMA to SO-239 adapters are way-stupid-over-priced as far as I can tell, but most of the rest are just ugly expensive, same as everywhere else... Adapters and connection cables and fittings are going to wind up more expensive than the VNA itself, I am afraid.) -- Wes Will N9KDY |
Re: Just got mine. Looking it over.
And you can always communicate directly with the ChibOS to get data in textAh!! THAT is what I needed. CLI it shall be. Thanks. Do you know if it is limited to 9600 BPS (BPS not BAUD)? My serial ports go a lot faster than that, and I have some non-Chinese-pirated-JUNK USB-to-RS-232 converters.... No, I do not participate greatly in the distro wars. I've just had it up to my ears with hearing the lie about "sudo" being a security feature. -- Wes Will MS IT (InfoSec) N9KDY |
Re: SOLT calibration vs. TRL
Dow-Key Microwave 411C-220832 12V relays I got a handful from equipment that we tossed into recycling at worksites. They never seen a signal larger than -10dbm and are perfect for circuits like this. None of them are older than 5 years and if they have switched more than 10 or 15 times in that time frame I would be utterly surprised.
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Bilbo On 10/15/2019 6:44 PM, alan victor wrote:
That is a nice solution. Who is the manufacturer for the relay? Quality SMA packaged relays are not cheap! |
Re: Nanovna-F is here
Where did I purchase? eBay and it took about 4 weeks to arrive.
Why three, now 4, vnas? I wanted one of each of the identified versions to test whether one was better. Whether shields made a difference in performance. Those tests are done and now I am paring down to two...... one mounted in my lab and one for my toolbox for the field. WA8TOD |
Re: Another ebay deal?
Nigel Gunn, G8IFF/W8IFF
But the Taobao website is in foreign.
On 15 October 2019 at 22:03 SM Ling <sm.ling11@... mailto:sm.ling11@... > wrote: Nigel A. Gunn, 1865 El Camino Drive, Xenia, OH 45385-1115, USA. tel +1 937 825 5032 Amateur Radio G8IFF W8IFF and GMRS WRBV701, e-mail nigel@... www |
Re: Just got mine. Looking it over.
Ahh the linux holy wars. I can assure you that nanovna-saver works fine on
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Fedora. It's a pure python program though it needs some libraries that are available in the repository but the packages are named slightly differently in different distributions. The pip3 instructions should be consistent, though. I think the other software choices are windows-specific. At least by report, the hardware communication under wine isn't smooth. And you can always communicate directly with the ChibOS to get data in text mode using a terminal program. For instance minicom at 9600 8N1. The prompt is ch> and 'help' gives a list of commands. Paul Alfille K1PHA On Tue, Oct 15, 2019 at 6:22 PM Rune Broberg <mihtjel@...> wrote:
Hi Wes, |
Re: errors of "error" models
Dr. David Kirkby from Kirkby Microwave Ltd
On Mon, 14 Oct 2019 at 23:53, yza <yzaVNA@...> wrote:
#47 : Once Again Hello, I am sorry, but you keep giving links rather than comment is very tiresome for me. | Finally, allow us, please, to comment that, in our humble | opinion, regarding 'Understanding', there are the following Your comments such as those above about the abilities and attitudes of different people is seen as rude by myself. Dave -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Fairly good raw uncorrected source and load match - based on one sample
Dr. David Kirkby from Kirkby Microwave Ltd
One of the parameters specified for a VNA is the
* raw uncorrected source match and * raw uncorrected load match. The better the raw performance, the better the corrected performance. I measured these best I could using my 8753ES VNA. Had these been poor, I would have tried to improve them. But based on my sample, it is not worthwhile trying to improve them. My procedure was 1) Set 8753 to its minimum output power which was -22 dBm, as its default output (I think +5 dBm), would have overloaded the NanoVNA. 2) Use a cable that came with the NanoVNA it is it quite flexible. 3) Added a 2 dB attenuator on the cable, for no other reason than to protect my calibration standards. 4) Set the 8753ES VNA to use the 85033D or 85033E calibration kit. This has the same parameters as my 85052B 5) Calibrated up to 3 GHz, which is the limit of my 8753ES - I do have a 20 GHz VNA, but below about 860 MHz, the 8753ES has better performance than the 20 GHz VNA. 5) Measured return loss of port 2 with the NanoVNA powered on and off. There was some difference, but only a few dB. As you can see from the photograph, the worst return loss on the load is 17.7 dB. 6) I measuring the source port with the NanoVNA powered on. I could find no way to stop the source completely messing up the measurements. Setting the frequency down below 100 kHz still screwed up measurements at 900 MHz. There were huge spikes. Note that the 8753ES VNA source power would have been around 10 dB less than the NanoVNA output power. Ignoring the very significant spikes, I do believe that the return loss of the source wasn¡¯t changing much whether the NanoVNA was powered up or not. Anyway, the worst case return loss at the source, whilst powered off, was 28 dB. In comparison, the guaranteed performance of my 8720D VNA over the range of 50 MHz to 2 GHz is *HP 8720D (guaranteed)* *Source match: 12 dB* *Load match: 22 dB* *NanoVNA (sample of 1)* *Source match: 28.0 dB* *Load match: 17.7 dB* So my one sample, the NanoVNA had a much better source match than the 8720D, but a little worse load match. Since I know that the NanoVNA was getting worse as the frequency was swept up to 3 GHz, if I did add the firmware that went to 1500 MHz, I might consider adding a small attenuator or resistor on the load to improve the load match, but to be honest I am only likely to do reflection measurements up to 1296 MHz on the NanoVNA, so the match at port 2 would be irrelevant. I didn¡¯t think until after I had performed a 1-port calibration on the 8753ES, that it might have been worth measuring the isolation between the two ports on the NanoVNA. The 8753ES has a system dynamic range of 110 dB, which would have dropped to 90 dB at a much reduced output power. Probably good enough, but if not reducing the IF bandwidth, increasing the output power and averaging would have all helped. Anyway, I thought it interesting, and based on my sample at least, any attempt to improve the match at the ports would be best done on the receiver port rather than the source port, but it¡¯s pretty good. -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: errors of "error" models
#49 :
first details of our final report 1 : nominal values comparison : our [NanoVNA] ~ our [VNA] - #30 : our final report 1 - 6 October 2019 : /g/nanovna-users/message/4179 - Hello, Allow us, please, to present the first details of our final report 1 regarding the Nominal Values of Rho for our [ref2007box], as they resulted by using our [VNA] and our [VNA]: Rho Magnitude: [VNA] : CYAN - pre-calibrated [VNA] : BLUE - Nominal Values [NanoVNA] : MAGENTA - pre-calibrated [NanoVNA] : RED - Nominal Values: Rho Argument: [VNA] : CYAN - pre-calibrated [VNA] : BLUE - Nominal Values [NanoVNA] : MAGENTA - pre-calibrated [NanoVNA] : RED - Nominal Values: Sincerely, gin&pez@arg 49# |
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