开云体育

Hi Oristo,

I uploaded it again. You can get it from the same link:

neb

it requires Android 7+

I have not tried, but:
Amazon Fire 7 tablet is on sale for US$30


My understanding that it is based on Android 7+

and can be tweaked to use Play Store apps

and supports USB OTG
.. so may work for Android NanoVNA WebApp

Hi neb -

The software is under development, but if you are interested you can
get it from here:

That URL expired after 1 week.

Thanking everyone for their responses. I was able to resolve the issue by performing a screen calibration using the Touch Cal function in the menu

Hello Norbert,
looks like a bug to me - I'll be sure to check it out and try to get it
fixed :-)

--
Rune / 5Q5R

I placed an order on EBay for a low priced NanoVNA from dowjors3236. He did not have a lot of feedback at the time.
I knew I would get either the VNA or my money back.
Got an email that it was going to shipping and a tracking number.
Kept checking the tracking number and it never said shipped.
When the delivery window ended, I filed with EBay, after leaving negative feedback for vendor.
After I filed, vendor requested EBay open a case.
The next day I received a refund because tracking number was not valid.

Vendor now has a lot of negative feedback, do not know why EBay has not booted him.

At least I got my refund.

Glenn

--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

Hi Rune,
the reset reference button is not working for the S11 & S21 LogMag (dB) window (pls see attachments).
If I hit reset reference nothing happens on this window. Reset right on this window works fine.
Is this per design or a bug?

Kind regards
Norbert, DG1KPN

Hello

I just received my NanoVNA -f (4.3 inch display) . When I try to select a menu option
The options disappear. ( No green highlighting unless you use the jog wheel)
Is a stylus needed?

Bob
=============================

Bob,

You need the nanoVNA-F group:

/g/nanovna-f

David
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

Have problem shown up specifically with nanoVNA Saver? I am running Pyton 3.8 and it appears to be working just fine.
-rick

Bob did you remove the plastic protective cover from the screen?

I just mine today too and it's wonderful!

Hello

I just received my NanoVNA -f (4.3 inch display) . When I try to select a menu option
The options disappear. ( No green highlighting unless you use the jog wheel)
Is a stylus needed?

Bob

How about adding the SWR display like 5.1 but keeping the smaller fonts?

On the 5.1 version some of the top line data on the right side of the
screen gets clipped as well.

Sam Reaves
ARS W3OHM

Wayne, just don’t use Version 3.8 of python…its buggy…
I have this running fine on Catalina with v 3.7 of python.

Dana VE3DS

On Sat, 23 Nov 2019 at 16:57, Oristo <ormpoa@...> wrote:

I tend to be annoyed

Content is available by web searches including site:
groups.io/g/nanovna-users

<>

My comment was sent to nanovna-f, not nanovna-users. NanoVNA-users is open
to anyone to read, but nanoVNA-f is not.

--

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

Hi Sam,.??
I spoke to Dennis about this earlier as it's been this way for all of his larger font releases.?
Unfortunately, there is only so much room on the display and Dennis is trying to squeeze 4 traces of large font into an extremely small area.?
That is why hugen's larger font version is only 2 traces so everything fits.?
At least this version has the huge SWR display, and the bottom line isn't really that bad.....
73.... Larry



On Sat, 23 Nov 2019 at 2:19 PM, Sam Reaves<sam.reaves@...> wrote: I noticed on my unit the larger font is clipped at the bottom of the screen and at the top right.
Is there a way to change this?

Sam
W3OHM

Hi Kurt, hi David, thank you very much for your replies!

of course, the coax cables were calibrated at the far end with SOL isolation and through. The first calibration (picture 1), directly on CH0 and CH1 connectors served as a reference without cables, where I expected the best performance. After the various calibrations were finished, the 50 ohm cal standard was placed again at the end of the coax cable connected to CH0. CH1 was terminated as well to see the dynamic range of S21. I do understand that the NanoVNA has no error correction like the VNWA. What I wanted to point out with this test is, that with a certain length of coax cables the overall performance of the NanoVNA can be improved. Like in my case by using standard RG174U with a length of 70 cm or the M17/152 coax cable with 93cm length. I didn't expect the marginal performance of the short 20 cm high quality coax cable. I fabricated those because I thought they would perform at best.

We all know, RF is a science on its own, hi!

Hope that clarifies initial misunderstandings!


Best regards
Norbert, DG1KPN

I use Ansmann cells in my other projects.

Can sustain 2C charge + has battery management included.
At worst case in a Nanovna, don't charge via USB, but via your own preferred external charger ?

- Andy-

I noticed on my unit the larger font is clipped at the bottom of the screen and at the top right.
Is there a way to change this?

Sam
W3OHM

I got one also, as time passed I thought it wasn't coming but it just took 2 months. I ordered something else that came much quicker and I noticed on the tracking that it seems like it's the time of the month maybe. Like I missed the boat on the first order so to speak.?



On Sat, Nov 23, 2019 at 11:42 AM, eyelessmisfit<eyelessmisfit@...> wrote: FYI, bought one of the 'deal's ($21), from ebay. Got a tracking number and was told it had been shipped. Never arrived so i contacted the seller and got no reply. Ebay got involved when i contacted the seller, gave them 5 days to make good and when they did not, ebay gave me a full refund!EBay makes your purchase no risk, so go ahead and take a chance. Sometimes you get a good one.Ron

Hi Norbert
If I understand you correctly you calibrated the Ch0 port directly and then just connected the various cables to Ch0 port and terminated at the far end with a female 50 ohm load.
If so it is only a measurement of how well the various cable can "transport" the 50 ohm load to the Ch0 port and obviously there is various impedance transformation pending the quality and characteristic of the different cables. It has nothing to do with impact on calibration.
If you had calibrated at the end of the various test cables then you should see no difference but for the NanoVNA you will because is has no build in error corrections, it just relies on the performance of the measurement bridge.
The purpose of error correction is to compensate for the imperfection of the output impedance of the Ch0 port and the input impedance of Ch1 port, as you see for you test 5, which is the Ch1 port input impedance transmitted thru the test cable incl impedance transformation caused by that cable.
A golden rule is: Consider always a test cable as part of the equipment - the NanoVNA - when calibration at the end of the test cables and the purpose of the calibration process is to remote the influence of these test cables now being part of the calibration data saved in the NanoVNA/NanoVNA-saver. However for the NanoVNA there is till a small or large impact from the test cables as no internal error 6 term error correction (12 term error correction not possible as requires measurements of all 4 S parameter in one go. So second golden rule use high quality test cable and as short as possible
Sorry .. my contribution tends to be long and is actually missing info on how to calibrate correctly so S11 and S21 phase are in sync and the calibration is done at the SMA male adaptros reference plane and the FF adaptor phase delay also is removed in the calibration process
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af Norbert Kohns
Sendt: 23. november 2019 14:46
Til: [email protected]
Emne: [nanovna-users] Coax cable length influence on calibration

Hi all,
today I performed a NanoVNA calibration test to find out if the coax cable length and quality has any negative influence specially on the S11 return loss.

The calibration setup is 10kHz-900MHz at 808 points.
For the test I used high quality coax cable (M17/152) and standard coax cable (RG174U).
The reference test was done directly on the NanoVNA port connectors. For the thru test a 5 cm long semi rigid coax cable was used (picture 1).
Next, a 20 cm long M17/152 coax cable was tested (picture 2).
Then, a 93 cm long M17/152 coax cable was tested (picture 3).
And last, a 70 cm long RG174U coax cable was tested (picture 4).
Picture 5 shows the test result for the RG174U coax cable for S21.

All test conditions have been repeated. The differences between the two tests were negligibly.

One can see, that the coax cable length has some negative impact on S11, specially with the 20 cm long coax cable.
The quality of the coax cable plays obviously a minor roll.

Do the experts among us have an explanation why this is as such?

Best regards
Norbert, DG1KPN