Thank you Tuck.
A fundamental question that needs further investigation is the accuracy of the VNA instrument.
This has not been addressed nor have I seen a specification in the document. The basic instrument configured as a one channel, one port VNA or antenna analyzer has the usual errors that are corrected by the firmware. The basic errors are the reflection tracking, the source match and the directivity. The nanoVNA uses a resistive bridge not a directional coupler. I need to think about how to get a handle on these errors uncorrected and then corrected. As you know, the level of error correction is dependent on the quality of the calibration standards.
I suspect the original designer has worked through those details. They may even be in some of his software comment sections.
This is a topic for future work.
Alan
|
Re: Step by step instruction on firmware upgrade?
Yes, that does work. But I figured out this was broken SHORT calibration connector supplied contributing to wrong calibration data stored.
After making a replacement from cable to test this idea I managed to calibrate, save and measure the load I know all about.
Thanks all for help, guess I'd better order new set as I got half refund.
|
FFT "quadrature mixing", Hilbert transform and filtering DSP
|
Thanks Alan, Gary and Larry, This document is very useful indeed, good writeup. It might be useful to include a table of RLB vs dB, VSWR and R+jX. The range of the instrument one expects should be between -1dB and-40dB return loss as the maximum range. This translates to (-1dB) is equivalent to VSWR 17.4 or 869.56 ohms for an open load and 2.875 ohms for a shorted load. At the other end (-40dB) is equivalent to VSWR 1.02 or 51.01 ohms for an open load and 49.01 ohms for a shorted load. Equivalent R+jX should also be useful too but needs more data than just the RL. Can the Antenna analyser firmware do between than the 869 ohms max, otherwise it¡¯s not much use for long wires? Tuck m0tcc From: [email protected] < [email protected]> On Behalf Of [email protected] Notification Sent: Friday, August 9, 2019 7:04 PM To: [email protected]Subject: [nanovna-users] New file uploaded to [email protected] Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the [email protected] <mailto: [email protected]> group. File: NanoVNA Calibration Considerations and Procedure_v1.0.pdf Uploaded By: alan victor Description: NanoVNA RF Calibration v1.0 pdf NanoVNA RF Calibration Considerations and Procedure with references and introduction material for new users of the vector network analyzer (VNA). You can access this file at the URL: /g/nanovna-users/files/NanoVNA%20Calibration%20Considerations%20and%20Procedure_v1.0.pdfCheers, The Groups.io Team
|
Re: Step by step instruction on firmware upgrade?
Hi Sergei
I think you'd have a clearer idea if you used the PC software as this can
show you firmware info*. No version number but there is firmware build time
& date, so I think you could at least check if the firmware is changing.
Also the 2 trace aa firmware reportedly uses a larger font to the 4 trace.
*This is from an earlier post of mine:
"Apologies if this has already been suggested but pressing the FW info
button in NanoVNA 1.03 returns information on the Nano's firmware,
including build 'time'.
Might the build timestamp be usable as a way to tell the different versions
apart?
As a starter, my NanoVNA is a 2-trace 900MHz antenna analyser with build
time May 5 2019 - 08:35:00."
Best regards
Mike
73
Mike
toggle quoted message
Show quoted text
On Sat, 10 Aug 2019, 12:36 Sergei Moissejev, <sergei.mo@...> wrote: Thanks for answers.
I think need to bit clarify the issue which is: post-calibration I do not
see Smith diagram reacts to open/short/load as needed ans as seen on
multiple videos.
I did use BOOT pins and tried 3 last FW files - both aa (2 traces) and ch
(4 traces).
And I thought I'm using wrong firmware or this was not correctly flashed
for these reasons:
- when I power VNA after flashing I still see the same charts selects as
before with the same Start/Stop frequencies
- I also do see the same as before flashing reaction on load change
- Same marker 4 shown ass before flashing at the same position
Which suggests the user data (my settings + calibration details) are not
cleared and this is why I created the post thinking I'm doing something
wrong.
If interface change after flashing firmware is the only indication using
device only (I haven't checked with provided software on PC) that firmware
is actually installed,
then I'm confused with these settings persisted.
And I start thinking this could be just front-end issue which I need to
check with the magnifying glasses.
|
Re: Step by step instruction on firmware upgrade?
...And I thought I'm using wrong firmware or this was not correctly flashed for these reasons:
- when I power VNA after flashing I still see the same charts selects as before with the same Start/Stop frequencies
- I also do see the same as before flashing reaction on load change.. Based on May 05, 2019 release notes, I think that nanoVNA_900_AA_20190505.dfu is required >>first<<, to clear user data. Others do not..
|
Re: Step by step instruction on firmware upgrade?
Thanks for answers.
I think need to bit clarify the issue which is: post-calibration I do not see Smith diagram reacts to open/short/load as needed ans as seen on multiple videos.
I did use BOOT pins and tried 3 last FW files - both aa (2 traces) and ch (4 traces).
And I thought I'm using wrong firmware or this was not correctly flashed for these reasons:
- when I power VNA after flashing I still see the same charts selects as before with the same Start/Stop frequencies
- I also do see the same as before flashing reaction on load change
- Same marker 4 shown ass before flashing at the same position
Which suggests the user data (my settings + calibration details) are not cleared and this is why I created the post thinking I'm doing something wrong.
If interface change after flashing firmware is the only indication using device only (I haven't checked with provided software on PC) that firmware is actually installed,
then I'm confused with these settings persisted.
And I start thinking this could be just front-end issue which I need to check with the magnifying glasses.
|
Re: Step by step instruction on firmware upgrade?
Serge, Have a look a some of my earlier posts with photos of how I soldered a small push switch from a cellphone to the BOOT solder pads on my unit. That way, I can place the unit into flash mode by pressing the switch, applying power and then releasing the switch. Everything you need is in the firmware repository that you'll find in the last 30 posts or so. You'll want the 20190722 or 20190802 version. Do a search for 'drive' and download everything. Look at my DFU post... /g/nanovna-users/message/381
|
The only way this software would work is if it supports the very same serial interface command set of the nanoVNA. Look in the files section for the command ref doc
toggle quoted message
Show quoted text
On Fri, Aug 9, 2019 at 05:49 PM, Mike wrote:
Hello.
Can someone test if nanovna will work with
?
I use it with my old VNA, wonder if I could use with new device.
Thanks, Mike
|
Re: Step by step instruction on firmware upgrade?
2 traces is fine. However, to get 4 traces will require a firmware change. The CAL process for 2 traces is no different than 4 traces. Of course you have no S21 measurement, but you may still follow same CAL procedure.
|
Hello.
Can someone test if nanovna will work with ?
I use it with my old VNA, wonder if I could use with new device.
Thanks, Mike
|
Step by step instruction on firmware upgrade?
Hi.
I got mine from ALI with 2 traces only with no manual and seems the only option to get 4 and then follow correct calbration procedure is to flash new decent firmware.
While I see discussion covered which firmware is good, but there were no instructions on how to you change it.
Can anyone share successful experience please?
Serge / M0TLN
|
Re: Some basic load measurements
There are no mixers within the Si5351A. Mixers are SA612A: Some 600MHz energy may be intermodulation aliasing between 300MHz fundamental and 900MHz third harmonic, not just second harmonic by transfer function asymmetry.
|
Re: Some basic load measurements
There are no mixers within the Si5351A. Whatever generated is done by fractional synthesis from the crystal clocks. There is another slightly different frequenc output that drive the mixer detectors. This is necessary as there are no antialiasing filters.Sent from my Samsung Galaxy smartphone.
toggle quoted message
Show quoted text
-------- Original message --------From: Oristo <ormpoa@...> Date: 09/08/2019 19:36 (GMT+01:00) To: [email protected] Subject: Re: [nanovna-users] Some basic load measurements Hi Peter -> Even harmonics are caused by asymmetry, right?? Is that something that can be controlled in this source chip?Yes, indirectly, by changing amplitude of signals into the mixer(dominant distortion contributor).
|
Re: AliExpress and NanoVNA supplier get 5 stars
Mine took 3 weeks.?Sent from my Samsung Galaxy smartphone.
toggle quoted message
Show quoted text
-------- Original message --------From: g1dtf@... Date: 09/08/2019 19:16 (GMT+01:00) To: [email protected] Subject: Re: [nanovna-users] AliExpress and NanoVNA supplier get 5 stars How long did it take Guangyi0016 to ship your order. I have ordered one from them and still waiting for it to be shipped (the supplier is processing your order is the msg on AliExpress).
|
Re: Some basic load measurements
Hi Peter - Even harmonics are caused by asymmetry, right? Is that something that can be controlled in this source chip? Yes, indirectly, by changing amplitude of signals into the mixer (dominant distortion contributor).
|
Re: AliExpress and NanoVNA supplier get 5 stars
I ordered mine the last week of June.
5 days later, I contacted the seller and asked when they were shipping as I heard nothing at that point.
I got a reply back that they had just shipped it.
A few of us have ordered from that seller and have received the device in North America after about 3 weeks.
YMMV
toggle quoted message
Show quoted text
On Fri, Aug 9, 2019 at 01:16 PM, <g1dtf@...> wrote:
How long did it take Guangyi0016 to ship your order. I have ordered one from
them and still waiting for it to be shipped (the supplier is processing your
order is the msg on AliExpress).
|
Re: AliExpress and NanoVNA supplier get 5 stars
How long did it take Guangyi0016 to ship your order. I have ordered one from them and still waiting for it to be shipped (the supplier is processing your order is the msg on AliExpress).
|
Hello,
This email message is a notification to let you know that a file has been uploaded to the Files area of the [email protected]
group.
File: NanoVNA Calibration Considerations and Procedure_v1.0.pdf
Uploaded By:
alan victor
Description:
NanoVNA RF Calibration v1.0 pdf
NanoVNA RF Calibration Considerations and Procedure with references and introduction material for new users of the vector network analyzer (VNA).
You can access this file at the URL:
/g/nanovna-users/files/NanoVNA%20Calibration%20Considerations%20and%20Procedure_v1.0.pdf
Cheers,
The Groups.io Team
|
Re: NanoVNA software on windows 10 x64?
I've only been using it for a week or so, but no problems on my Win 10 x64 machine (Win ver.1809). Have fun!
|
Oristo
F4WCV
Mike
Brent DeWitt