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Mine too. It got so boringly stable that I sometimes booted it for (small) fun

There is now Google group for NanoVNA 2 and 3. You might want look at there too. Then there is this

Thank you very much Roger taking your time for explaining me all of that.

Let's say that I will manage to make repeatable measurement on nanoVNA, so without PC, keeping it in the same position and off interference.
When you're saying that rubber duck antenna is only have of the system, does it mean that when I mount different antennas to the radio some of them will have higher and some lower SWR than measured on nanoVNA.

"you will see the SWR varying all over the place" - is it too optimistic thinking that I can measure if SWR is ~1.5 and not >3.0 or you mean smaller discrepancy?

My XP installation was extremely stable. I don't remember any crash caused by XP. But faulty application programs could indeed crash the whole machine. The technique to achieve a highly reliable XP system is to weed out such faulty applications.

I understand that newer Windows versions do a better job encapsulating each application, so as to shield the OS and the other applications from a faulty program. But I'm no expert on that matter... Just a user, and electronician.

With Windows 98, before, I had frequent crashes.

On Sun, Sep 4, 2022 at 04:26 PM, Tish wrote:

My idea for use of NanoVNA was for checking cheap (chinese) antennas for HH,
that I have available locally, to get more or less precise SWR reading.

If you are referring to testing "rubber duck" antennas for hand held transmitters you need to be aware of a few things. The "rubber duck" is only half of the antenna system. The other half is the metal case of the hand-held and the capacitive coupling between the operator and the handheld case. Manufacturers will do their tests and tuning with the antenna mounted on the radio and a test jig connection to the SWR measuring equipment.

If you just screw the antenna onto the NanoVNA you will not get very good results because you do are not replicating it mounted on the radio. If you try it you will see the SWR varying all over the place as you pickup the NanoVNA and change its orientation. If you connect a USB cable to a computer it will vary even more because you are changing the grounding of the antenna.

What some guys do when testing HT antennas for SWR comparison purposes is use a round pizza pan as the ground plane. They mount a matching connector in the center and then run a cable to the NanoVNA. They suspend the pizza pan/HT antenna away from other objects and then make their measurements. This setup only measures the resonant frequency(s) and SWR. It does not tell you anything about antenna gain or how well it radiates.

Roger

On Sun, Sep 4, 2022 at 04:30 PM, Tish wrote:

Does separate RF choke have big impact on SWR measurements?

It all depends on the antenna. If you have a dipole, which is a balanced antenna, and you connect it directly to an unbalanced transmission line (like coax) the outer surface of the coax shield is connected to one leg of the antenna. So it becomes part of the antenna and radiates. When you change the length of the coax or ground it at the radio end this will affect the SWR and the resonant frequency. If a current balun is installed at the feedpoint it will "choke" the current flow on the coax outer shield and considerably reduce this effect.

The J-pole which is a common VHF antenna will also radiate on the coax and the SWR will change as you hold the coax or change the length. Once again a choke is required.

Any decent book on ham antennas will discuss this issue. The ARRL Antenna Book is a good reference.

Roger

Are there any advantages of faster CPU, more memory in H4 (vs H) model for occasional use? I have good eyesight so 2.8" doesn't bother me. SD Card is a plus (but not worth the price difference). Does separate RF choke have impact big on SWR measurements?

My idea for use of NanoVNA was for checking cheap (chinese) antennas for HH, that I have available locally, to get more or less precise SWR reading. As I am grateful for explaining difference between H and newer V2 models, they seem to be overkill for my current needs. I guess I can sell H model if time for upgrade comes or leave it as a backup...

When you put the NanoVNA into DFU mode and plug it in do you hear the "bing" from Windows that it recognizes the device. If you look in Device manager under USB devices do you see that device is in DFU mode?

Post a screenshot if possible.

Roger

On Sun, Sep 4, 2022 at 03:43 PM, Nick M wrote:

I cannot find the driver for the virtual com driver ,
I have VNA that i would like to update, NANO VNA-H model
This this over a year old and i cannot get it to calibrate to 50 ohm
I tried everything .
I can get to the dfu boot mode , but the computer does not have the driver .
for windows 10
Version 1.0.70

We need more info to help you out...

Why do you think your problem is with the firmware? Are you following the calibration procedure correctly and resetting before you calibrate? After calibration when you put the 50ohm load on what do you see on the display?

When you put the -H in DFU mode and plug it into the computer do you hear the "bing" sound from the computer? If you do the driver is OK and then you can run the firmware update software. What firmware upload package are you using to do the update?

Roger

I cannot find the driver for the virtual com driver ,
I have VNA that i would like to update, NANO VNA-H model
This this over a year old and i cannot get it to calibrate to 50 ohm
I tried everything .
I can get to the dfu boot mode , but the computer does not have the driver . for windows 10
Version 1.0.70

any help please .

On Sun, Sep 4, 2022 at 11:56 AM, Tish wrote:

Hello Everyone.

I'm planning to buy my first NanoVNA for antenna SWR measurements (2m/70cm).
Where I live the only reasonable option is zeenko store.
Most of the time I'll be using PC software and my question is if it worth it
to pay more for H4 v4.3 (~86USD) version over H v3.6 (~50USD). I know that H4
is better, but that difference in price seems a little steep.
Thanks, tcs.

If all you are on a budget and only interested in is SWR measurements the H v3.6 will do the job. However the bigger screen of the -H4 and the fact that it can record screenshots to a SD card makes it worth the extra money.

You have to be careful when connecting the NanoVNA to a PC. The USB cable and the PC are connected to the ground of the NanoVNA and hence to the shield of the coax cable. So they become part of the antenna system and your measurements may be affected. This is not a problem if you don't have common mode current on the surface of the coax shield but in some cases you will if the antenna system does not have some type of RF choke. The way to tell is to observe the NanoVNA display with and without the USB cable attached and see if it changes.

Roger

get a v2 (or one of its clones, cousins, brothers and sisters)

zeenko?? then an saa2n comes to mind

or any of those 3plus plus gig devices

all the "genuine" nano have a clock tha goes up to around 280 .. some 300 megs ... and all above is measured with "harmonics"

while the newer v2s (v2, v2plus, saa2n,v2plus4, litevna 62+64, vna6k ... just to name a few) have a clock that goes over 3 gig (some to 4.4 and some even over 6 ghz)

hmm you may ask why take that for "only 2m and 70cm"?? at first ... its nice to have a clock that goes higher and not to measure with overtones of the main clock (better results and more dynamic range)

next is ... maybe you once want to measure at 23 or 13 cm ... (say for atv or for? a sat dish?? .. whatever) ... and then you do not need to buy ANOTHER vna

better spend a bit more ... buy a GOOD unit (4 to 6 ghz is no luxury) ...

i recommend one with a 4 inch screen (those units with 2.8 are nice for the shirt pocket but you need reeading glasses for it)

a metal case ?? yes ... should be in a metal case

sma or n sockets??

hmm n socket is more robust ... so if you use it often ... n socket is ok

but you also can screw an sma to n socket adapter on a vna with sma sockets (used as port saver and use n cables then)

so ...

look for

a vna2 (clone cousin bla bla)

metal case .. with sockets to your needs ... sma is NOT made for several screw unscrew usages so either use n ... or sma to sma port saver (male femal adaptor)

4 inch screen

and 4 or 6 ghz max frequency

no that is not for 50 bucks ... grin

greetz sigi dg9bfc





Am 04.09.2022 um 17:05 schrieb Tish:

Hello Everyone.

I'm planning to buy my first NanoVNA for antenna SWR measurements (2m/70cm). Where I live the only reasonable option is zeenko store.
Most of the time I'll be using PC software and my question is if it worth it to pay more for H4 v4.3 (~86USD) version over H v3.6 (~50USD). I know that H4 is better, but that difference in price seems a little steep.
Thanks, tcs.

Look into Vbox (VirtualBox).. free and lets you run several different
operating systems in addition to a base one. Win 10 in my case.
I'm installing 100 meg of XP Pro for my old stuff and 700 meg of Ubuntu in
my second 2gb ssd internal drive in a Dell I7559 laptop that has an i7 cpu
and max RAM.




You could preserve your Win7 under Vbox. Likely to run the same or faster.

--
Chuck Cole ?K4TZO

XP is a nice operating
system, perhaps better than W7 or W10

XP still crashed quite often (blue screen). I only planted Seven once and again, I should have been more patient.

During the passage Xp -> Seven, I lost the use of Autocad versions and, after the filth that Dasault made us about Draftsight, I have to be content with nanoCAD which is clearly below the aforementioned, especially in terms of speed.
--
F1AMM (Fran?ois)

-----Message d'origine-----

De la part de Leif M
4 septembre 2022 01:09

Yes, I have a lot software which takes a lot of time reinstall. About 1,5 TB. I made a Windows 10 SSD boot disk for KiCad. But if W7 works, why fix it. XP is a nice operating system, perhaps better than W7 or W10, but it does not understand large Hard disks or Ram.
That is, this machine can boot into W10 or W7 and I want to have NanoVNa on both.

I cannot find a driver for Win 11 for use with stm32080. Where do I find a driver or should I use another tool to make the firmware upgrade?

Ohhh - big thanks :D - will test during the weekend as I am loooong way from home at the moment. Thanks for the effort providing a fix ?

Cheers

C

On 02/09/2022 14:11, Diane BONKOUNGOU wrote:

"You have to make a 4 layer stack as you've pointed out" I am wondering if

it's possible to put hole in my structure like via to connect the different
layers to the GND.

All you need to do is to put in a short meta cylinder as a via between the layers you need to connect, No hole is needed. You don't need a hole since metal takes priority over the dielectric. A short square via might be better as you can line it up to the mesh, so that it is detected.

Brian


--
Brian