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Re: Should I upgrade firmware, and if so which version to use?
But if your wife wants to "upgrade" her shoes do you tell her no? :D
The bottom line with upgrades is stuff works better. Who doesn't want that? The developers are very quick to fix bugs so you can be pretty confident that the latest stable version that is out there won't be buggy. Could a new bug surface that no one has caught yet? Sure. That is true of literally everything that uses software/firmware. But it probably won't be anything major if it took a while to surface. 73 -Jim NU0C On Tue, 12 Jul 2022 04:10:55 -0700 "alex" <alex@...> wrote: Right. The question should be "am I missing something I want to use right now or am I using something that has a bug and should be repaired right now." If you don't know what you're missing and all your tests are performed well, why should you upgrade. Yeah some bugs might be solved, but others could enter just your tests. This is like a married man who wants an upgrade of his wife, is it necessary, is it broken? |
Re: Should I upgrade firmware, and if so which version to use?
All the large engineering projects I have worked on have had a "tool freeze" date. Once the software tools for the project have been chosen we update to the latest known good version, and then keep that version for the duration of the project. That way everyone has the same tool versions; all the tool bugs become quickly known, along with their workarounds; and no new bugs appear late in the program.
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Re: Should I upgrade firmware, and if so which version to use?
I have a NanoVNA H4. One thing I like about recent firmware updates is
that, when you save a calibrated frequency range in the memory, it then actually displays the frequency range that is stored. Older versions didn't do that. Zack W9SZ On Tue, Jul 12, 2022 at 12:15 AM Jim Shorney <jimNU0C@...> wrote: <> Virus-free. www.avast.com <> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> |
Re: Should I upgrade firmware, and if so which version to use?
"Can I upgrade the firmware and obtain additional functionality?"
Yes. You didn't say how old your NanoVNA is, or its firmware version - but, if you carefully make note of its current version, find, download and save that version, then you can install any newer version. Test any new ones, then, and you can still go back and re-install your current version. If your current one is more than a year old, there will be many new features in newer versions. You can 'swap around' firmware versions sort of like you can swap pairs of socks. Well, it will be harder the first time. There's an old "AA" version that's nice for use testing antennas outdoors - it has an extra-large text font for much easier readability in brighter light. The "AA" seems to be for "Antenna Analyzer". Be sure to read up about changing firmware, and maybe also watch some videos about doing it. The first time or two will seem a little tricky or difficult, but that's mostly just because it's something new (to you). Good luck, and have even more fun with your Nano! -- Doug, K8RFT |
Re: Should I upgrade firmware, and if so which version to use?
Right. The question should be "am I missing something I want to use right now or am I using something that has a bug and should be repaired right now." If you don't know what you're missing and all your tests are performed well, why should you upgrade. Yeah some bugs might be solved, but others could enter just your tests. This is like a married man who wants an upgrade of his wife, is it necessary, is it broken?
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Re: Common ground and 2-port measuring
Hi Victor,
Thank you for your update and information. There are different ways to measure CMC performance as there are different 'lumped' component models of a CMC taking account of parasitic elements of a practical or real component. There is merit in making a test configuration and method for how the component will be used in a particular application. If I were designing and making a CMC filter, I would use a different method of testing to my simple proposal, one very similar to your preferred configuration. I do not have any rf 1:1 center-tapped baluns so am not able to compare results. If and when you have time to make comparisons, I would be very interested in your findings. Kind regards Ed, G8FAX |
Re: Should I upgrade firmware, and if so which version to use?
Of course you should still upgrade to the latest. You will get bug fixes, performance improvements, and new features. FREE!
73 -Jim NU0C On Mon, 11 Jul 2022 10:50:32 -0700 m2walter@... wrote: You're correct. I was thinking about it and tried it: the NanoVNA does go to 900 MHZ. And all this time I thought that since the default stop freq that it 'boots up with' is 250 Mhz that it was not capable of going higher. That will teach me to test before opening my mouth. |
Re: Common ground and 2-port measuring
A clasic way to explain this was to connect 2 ports with coax,
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connect the coax shields on 2 ports with a short piece of wire and try to measure the current in the wire but I like this graphic, it is quite intuitive. On Mon, 11 Jul 2022 at 23:52, DP <dpoinsett@...> wrote:
On Sun, Jul 10, 2022 at 08:09 PM, Jerry Stuckle wrote:Actually, that's a common, but incorrect statement. Current - RF orotherwise- always flows along ALL available paths, split according to the inverseofthe resistance.Hi Jerry, |
Re: Common ground and 2-port measuring
On Sun, Jul 10, 2022 at 08:09 PM, Jerry Stuckle wrote:
Actually, that's a common, but incorrect statement. Current - RF or otherwiseHi Jerry, You're absolutely right. It's not all or nothing. A semantically better way to say it is: RF current always favors the path of least impedance. The degree of "favor" is divided between paths according to impedance. That's consistent with your point. In the case of Miro's original question about problems with RF current flowing in the internal ground connection between the ports, the answer is still no. The impedance in PATH1 of his drawing (attached) is too high for there to be a problem even though the DC resistance is probably very low. The RF return current is confined almost entirely in the transmission line. The attached drawing shows a double-sided PCB. The bottom has a solid copper ground plane. The top has a single trace between the ports. An RF input signal is applied between the trace and ground plane. The load is connected between the trace and ground plane. At 10 MHz the RF return current will be confined to a narrow path in the ground plane directly below the top trace. Openings in the PCB provide isolated current paths A and B for easy measurement. RF current in these paths will be negligible. At RF frequencies, the impedance through paths A and B is high primarily due to the geometry. The further the distance from the trace, the higher the series inductance and the lower the parallel capacitance. These both mean higher reactance. The area in the ground plane directly below the trace has the lowest impedance. That's where almost all the return current flows even though it's surrounded by an area with very low DC resistance. Like so many things with RF, this behavior is counter-intuitive to our understanding of what happens with DC and low-frequency AC. Dave NU8A |
Re: Perfect SWR with dummy load, but huge with antenna
The measure of a "good" antenna is how well it performs. When I lived in a
house with a lot bigger yard a few years ago I had a 40 meter vertical full-wave loop antenna (~12 feet high and ~58 feet long). It had 5.5 dB of gain over a dipole according to NEC2. It performed almost as well as a 40 meter Yagi antenna in its peak directions. It was the best 40 meter antenna I have owned. I now live on a much smaller property and can't fit that antenna in the yard. I have an MFJ 1796 vertical. It does "OK" on 20 meters and higher, but I'm severely disappointed in its performance on 40 meters. Maybe the other antenna spoiled me. Zack W9SZ On Mon, Jul 11, 2022 at 12:14 PM W0LEV <davearea51a@...> wrote: Yes, indeed...... The measure of a "good" antenna is not SWR.<> Virus-free. www.avg.com <> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> |
Re: Should I upgrade firmware, and if so which version to use?
You're correct. I was thinking about it and tried it: the NanoVNA does go to 900 MHZ. And all this time I thought that since the default stop freq that it 'boots up with' is 250 Mhz that it was not capable of going higher. That will teach me to test before opening my mouth.
This makes me feel better: less worried 'bout changing firmware. Mark Walter |
Re: Common ground and 2-port measuring
Hello Ed,
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I have not much now to look into this, but this article: Gives your method (Fig 3b and Fig 7a. So one can measure some aspects of the choke. I need to check how close this is to the DM mode. All the best, Victor Op ma 11 jul. 2022 om 08:20 schreef Ed G8FAX <ed@...>: Hi Victor, |
Re: Should I upgrade firmware, and if so which version to use?
it should go to 900 (3rd harmonic) or 1.5 g (fith overtone)
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dg9bfc sigi (sorry i can not help with fw cause i am a v2 user that has a clock to over 4g) Am 11.07.2022 um 18:44 schrieb m2walter@...: I have an original NanoVNA: it only goes up to 250 MHz. Can I upgrade the firmware and obtain additional functionality? If the firmware can be upgraded which version should I load. Tks. |
Re: Perfect SWR with dummy load, but huge with antenna
Yes, indeed...... The measure of a "good" antenna is not SWR.
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Of course, a 1:1 in a 50-ohm non-reactive system is essential to keep the transmitter output stage happy, but does not measure how good an antenna is at radiating the RF energy fed to it. Again,......SWR is NOT a single proper indicator of a "good" antenna. Dave - W?LEV On Mon, Jul 11, 2022 at 6:34 AM olivier LAVAUX <f6cng.68@...> wrote:
be careful not to have a dummy load @swr1.1!-- *Dave - W?LEV* *Just Let Darwin Work* --
Dave - W?LEV |
Re: Ubuntu PPA or .deb installation
I build a deb package with the command "DEB_BUILD_OPTIONS=nocheck python setup.py --command-packages=stdeb.command bdist_deb". You need the debian package "python3-stdeb" (Python to Debian source package conversion plugins for distutils) and maybe some more development packages.
As a quick start see this documentation: |
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