开云体育

3 part video tutorial

Link added in /g/nanovna-users/wiki/User-Guides
( although since not specific to nanoVNA,
arguably should be in /g/nanovna-users/wiki/External-links )

Ok. Then how do you handle calibration and test. Is cal done with the barrel adapter in place? Or do you cal at the vna ports
and then electrically de embed the adapter?

Hi Herb,

"Pmax,
I have not performed any updates (see attachment). Two other users have provided feedback at groups.io of their NanoVNA-H4’s locking up when setting the center frequency above 1.5 GHz, so it is not just my unit. So far you are the only person who has said they do not have this problem. One user did update their NanoVNA-H4 but said that the center frequency lock up problem still remained."

I watched and read the problem and came to ask:
is this problem even without USB connection?
Does it return a negative number even when there is no connection between your computer and nano?
I can't control it myself, just a thought. I think my ePacket is stuck, but now I see it in the country this morning. :-)

Thank you for your attention.
Gyula

This is very interesting, but I hope it is possible to buy from Europe.
What kind of calibration standards are good enough.
It will be interesting to see how bad some very low cost 2.4G WLAN antennas really are.

Hi, Do please put in a suggestion of accepting Paypal (even if they have to charge us extra). In Europe, some banks are not happy with the buyer passing card details to countries where they are not involved in retail banking. The first the buyer will know is when his card is refused or even blocked.
........................

On Fri, Jan 24, 2020 at 09:59 PM, <tonyg1hmo@...> wrote:

"… can anyone tell me is it possible to save a configuration? …
=======================================================
Tony,
Refer to the Menu Structure Map that came with the NanoVNA-H4. CAL->SAVE->SAVE 0 will save the current calibration and configuration to memory location 0 which the NanoVNA-H4 loads at power-on. You can also save to memory locations 1-4 but you have use the RECALL menu to manually recall the saved configurations.

- Herb

Hi,
I have just purchased a Nanovna H4 from Hugen's Alibaba store.
Very impressed so far with it, but can anyone tell me is it possible to save a configuration?
For example, when I switch it on, it initially displays all 4 traces, and covers (I think) 50khz to 900MHz, if I turn off trace 3 and trace 4, and set the start frequency to 1.5MHz and the stop frequency to 30MHz, can I save those settings so when I power it back on, it always starts up set to those settings.
I have set things how I want, however when I click save, the menu simply dissapears, from what I can tell, there should be the option to save to a memory sore.
Other than that, I am so impressed with it.

it has firmware 0.4.5-12-gea578a2
build time Jan 18 2020 - 23::13

Tony

nanovna-saver support is working, just waiting on a pull request:

The currently available hardware is all 2.8''. The 4'' display version will have to wait.

It will be mainly on taobao for domestic users. I'm not sure what they are planning to do for international orders yet, but it's not going to be on ebay or aliexpress (most likely their own web store). I'll post more info when it is available.

Final specifications:
System dynamic range (calibrated): 70dB (to 1.5GHz), 60dB (to 3GHz)
S11 noise floor (calibrated): 50dB (to 1.5GHz), 40dB (to 3GHz)

On Fri, Jan 24, 2020 at 08:10 PM, Gabriel Tenma White wrote:

" Ok it looks like I need to do more work on the cal kit parameters. Previously the software only took S parameter files for cal kit definitions, and I've only added a "fine tune" UI which does length extension the configured S parameters (and adds parasitics for the load standard)."
============================================================================================

Gabriel,
I 've noticed a lot of recent work on the "VNA View" application for V2, but haven't noticed any recent work on the porting of NanoVNA-saver or the nanoVNA.py script. Will those applications also be ready at launch, or will they follow the introduction of the hardware in the near term?

Any pre-release info regarding the V2 performance specifications? Will the V2 display size match the 4" NanoVNA-H4 or was the 3.2" display you previously posted about the only viable candidate?

Do you know what channel you client is planning on marketing V2 device through?

- Herb

On Fri, Jan 24, 2020 at 07:24 PM, Ken Liao, AA6KL wrote:

" ..Thank you for helping me test out the firmware. I was using Ubuntu and didn't try it out at Windows..."
====================================================================================

No problem Ken. It would be nice to have a lab full of beta testers like Microsoft does but I guess you'll have to settle for us instead. If there is a useable platform for connecting to the NanoVNA-H4, one of the boards members is probably running it.

I eventually gave up trying to use the touchscreen and went to navigating the UI using the jog-switch. Even so, after doing a touchscreen corner to corner calibration and touchscreen test, registration and sensitivity using a stylus was not useable.

After, the firmware update, USB communication was toast even after I cycled power on the NanoVNA-H4 a few times. I was hoping to be able to perform a "clearconfig 1234" after updating but could never link to the NanoVNA-H4 via a serial connection. Loading hugen's firmware put things back in order.

I don't know how wide spread the greater than 1 GHz center frequency issue is. None of this group's member's have reported it not being a problem, while those that have responded are experiencing the same lock-up issue I have observed. hugen has left feedback that he is investigating the issue, but this being Chinese New Year he deserves to spend time with friends and family and hopefully hit the ground running afterwards.

My system is Windows 10 x64, i7, 12Gb.
regards,
- Herb

Ok it looks like I need to do more work on the cal kit parameters. Previously the software only took S parameter files for cal kit definitions, and I've only added a "fine tune" UI which does length extension the configured S parameters (and adds parasitics for the load standard).

The hardware hasn't changed since the December revision (V2_2), which is the revision they are using for production. The next hardware revision will be an experimental one, with changes like an amplifier on channel 0 and port 2 ecal features.

Here is one sample from production:
Note that the enclosure is still not finalized and for the first few weeks the VNA will be sold without an enclosure at reduced price I've heard. There are still some fit issues related to the connectors that need to be fixed and enclosure manufacturing will take some time as well.

Ken,I think you meant to say in the last paragraph that the MCU can NEVER be bricked as you will always be able to get back into dfu mode.?
... Larry



On Fri, 24 Jan 2020 at 10:24 PM, Ken Liao, AA6KL<kuohsing@...> wrote: Herb,

Thank you for helping me test out the firmware.? I was using Ubuntu and didn't try it out at Windows.? I will be out of reach of my lab computer for the following two days.? So it will take a few day to have the new formware fixed.

For the DFU format issue, I was using the dfu-tool to convert from bin to dfu format, and tested it with dfu-util.? Apparently, the generated format is not recognized by ST Micro's DfuSe Demo.? I need to find a better tool to do the conversion at Ubuntu.

The touchscreen calibration needs to be done through Configuration->Touch Calibration with jog switch after the firmware update.? I can? make it use the default one after each firmware update, instead of reading from Flash configuation.

I saw the USB serial issue too.? But once I unplug the USB cable, turn off and turn on the device, then plug in USB cable, the USB serial works.? I will verify if this is same for Windows.? In ChibiOS_18, the gcc compilation is quite aggressive and may cause race condition.? In Ubuntu, if I disable the LTO (Link Time Optimization) flag in gcc, the USB would work.? Making compile option -O0 (no optimization) also works, but the firmware size is 190KB!? Another potential USB issue is the device USB handshake with host by pulling down USB_DP pin.? This requires the R48 connected between USB_DP(PA12) and PA8, which is not polulated at this moment yet.? I will do more experiment to fix the USB serial issue.

Roger raised an interesting question about how to burn formware via USB with malfuntion USB serial. When pressing the job switch at powering on, the BOOT0 pin is connected to VDD, and MCU enters the DFU mode.? The DFU firmware is inside the ROM and cannot be modified.? This way, ST Micro can ensure that its MCU will be bricked (totally dead and un-recoverable) by bad flash content.

For the center frequency issue, I will wait for Hugen's fix and merge his code.

Ken

Herb,

Thank you for helping me test out the firmware. I was using Ubuntu and didn't try it out at Windows. I will be out of reach of my lab computer for the following two days. So it will take a few day to have the new formware fixed.

For the DFU format issue, I was using the dfu-tool to convert from bin to dfu format, and tested it with dfu-util. Apparently, the generated format is not recognized by ST Micro's DfuSe Demo. I need to find a better tool to do the conversion at Ubuntu.

The touchscreen calibration needs to be done through Configuration->Touch Calibration with jog switch after the firmware update. I can make it use the default one after each firmware update, instead of reading from Flash configuation.

I saw the USB serial issue too. But once I unplug the USB cable, turn off and turn on the device, then plug in USB cable, the USB serial works. I will verify if this is same for Windows. In ChibiOS_18, the gcc compilation is quite aggressive and may cause race condition. In Ubuntu, if I disable the LTO (Link Time Optimization) flag in gcc, the USB would work. Making compile option -O0 (no optimization) also works, but the firmware size is 190KB! Another potential USB issue is the device USB handshake with host by pulling down USB_DP pin. This requires the R48 connected between USB_DP(PA12) and PA8, which is not polulated at this moment yet. I will do more experiment to fix the USB serial issue.

Roger raised an interesting question about how to burn formware via USB with malfuntion USB serial. When pressing the job switch at powering on, the BOOT0 pin is connected to VDD, and MCU enters the DFU mode. The DFU firmware is inside the ROM and cannot be modified. This way, ST Micro can ensure that its MCU will be bricked (totally dead and un-recoverable) by bad flash content.

For the center frequency issue, I will wait for Hugen's fix and merge his code.

Ken

at 388 US for the kit. they have been putting lot of time on the tutorial
and not selling many the way I see it..


Le ven. 24 janv. 2020 à 18:28, Roger Need via Groups.Io <sailtamarack=
[email protected]> a écrit :

Ever wonder where the idea for this "RF Demo Kit" came from??

A company called MegiQ has been selling something similar for at least 4
years with their VNA..



Roger

On Fri, Jan 24, 2020 at 04:22 PM, Roger Need wrote:

How did you manage to get into DFU mode and reflash if the serial port was not recognized in Windows?
=================================================================

Hi Roger,
DFU Demo Recognizes the NanoVNA as a device in DFU mode not as a serial port. So it works even though a terminal program sees nothing attached. The actual logistics are above my pay grade, but I think that covers the gist of it.

On a side note, when you first boot the NanoVNA-H4 into DFU mode the screen goes completely dark during the process. This is different than when the 2.8" NanoVNA goes into DFU mode. Kind of freaks you out until you realize that's just the way it works; but the first time there's a "What did I do to my new -H4 moment".

- Herb

Herb,

How did you manage to get into DFU mode and reflash if the serial port was not recognized in Windows?

Ken,
I used DFU File Manager to convert your hex file to dfu format and then DFU Demo (not File Manger as I previously wrote) was able to load the converted file without error. I encountered the following problems after the upgrade was complete:

1. I could not get a good touchscreen calibration no matter how many times I tried. I had to resort to using the multi-function switch to navigate the UI.

2. The NanoVNA-H4 serial port was not recognized after the upgrade, so no CLI commands could be issued to the NanoVNA-H4.

3. The center frequency problem reported in is still present in your upgrade.

I loaded hugen's January 18th, 2020 release and touchscreen calibration worked, serialport communications was restored, the center frequency issue was still present.

I suggest users hold off on the upgrade until you look into these issues, unless they are adventurous.

Herb

Ever wonder where the idea for this "RF Demo Kit" came from??

A company called MegiQ has been selling something similar for at least 4 years with their VNA..



Roger

Those new to VNA's will find this 3 part video tutorial very informative. It starts off with the basics, then moves on to calibration and finally on how to test components. Topics like using port extenders, de-embedding, transmission lines are all covered. It is time well spent if you really want to learn about VNA's. Just turn off the music - it will drive you nuts...



Roger

"You can get as deep into the pool as you want, but the more you know, the better your measurements will be, and the better you'll know when the instrument is lying to you."
One of the best comments! You will always need to be aware of a lying instrument. The only remedy is knowledge of the instrument and measurement procedures. Get to know how port extensions work, what the effect is of an adapter in your signal path and how to measure stuff without an RF connector.
This cannot be learnt from a cookbook, only through hands-on experience.

Op 24-1-2020 om 23:00 schreef mdrandol@...: