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Looking forward to your review. Did you order with express shipping?

Roger

Perhaps, the displY can wait till the actual measurements were made and
logged for display.
This might help a noise reduction due to display drive signals.

Ok, great. If you are trying to look at the pass band insertion loss response while at the same time the rejection response, dynamic range may very well get in your way. If that sort of measurement is required than one method is separate out each measurement challenge. Go for IL first and then try to eek out as low a noise floor as possible while driving the filter with as much signal as the analyzer will tolerate. Unlike other vna's this has no BW adjust or video filter tweak. Although averaging helps quite a bit.

Jim,

I use Linux Mint 19.2 Cinnamon on my Chromebook and I believe I had trouble running nanovna-saver because qtxcb was missing. Try installing it with "sudo apt install qt5dxcb-plugin" and see if that helps. Mint 19.3 won't run on my Chromebook (no video) but otherwise there shouldn't be too much difference between Mint 19.2 and 19.3 to cause trouble with nanovna-saver.

Jerry AC9NM

an other suggestion:

Dig further back into the matching system. In our modern transceivers, the
match begins at the collector / drain of the output devices (the PA).
There is typically no attempt to do conjugation at that point, just bring
the impedance from the (generally) far left of the Smith Chart to something
significantly closer to the center of the chart. This must be accomplished
in a broadband manner.

Dave - W?LEV

--

*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*

After you get it installed, you can make a shortcut by right clicking on the desktop and select "Create Launcher here"
I just called mine NanoVNA Saver and browsed for an unused system icon. The command for my system was
python3.7 /home/andrew/nanovna-saver/nanovna-saver.py

Procedure may be slightly different with Mate. Also of course your path will be different as well.

As a side note, you can also install AntScope 2, the RigExpert software. It won't connect to the NanoVNA but you can open the saved files to play around with.
You'll want the Ubuntu 18.04 version for Mint 19.3

--
Andrew Harmon - KD5RKO

If so, then this is a bad solution to the problem. A photo.

I'm using 19.3 Cinnamon myself. If I remember correctly, I had to install a few dependencies first.
Try this first
sudo apt install python3.7 python3-pip python3-distutils python3-setuptools python3-wheel
then

git clone
cd nanovna-saver
python3.7 -m pip install .

Don't forget the space then . after install
then
python3.7 nanovna-saver.py
Should open after that. Let me know where you get errors.
Also I made a shortcut on my desktop to launch it.

Good morning Alan,
I did as you suggested,
I know where the issue is now.
I neglected to take into account the dynamic range of the instrument.
The filter is a 40 meter filter down -78 dB so I was in the noise floor.
I did a cal and tested the nano with precision attenuators from mini circuits.
-10, -20, -40, and putting them together -70.
Down to - 70 dB it reads within .25 dB.
It still would be good to know if the amplitude could be adjusted in the software.

Classic case of pilot error!

Thanks for your help
Ed

Filter response is very dependent on terminations. Higher load Z than filter designed load will increase coupling between filter elements, widening bandwidth and usually increases loss. Lower load Z will decrease coupling between elements and narrows filter bandwidth. Loss and ripple may decrease if the filter design was in Chebyshev region or loss could get greater if original design was Butterworth or Gaussian. The S21 input port Z is not very good so attenuator pad will help reduce the load variation. Spectrum analyzer has similar issue on its input. Any reactance in the load will detune the filter elements.

You did not mention the filter design frequency.

I have a nanoVNA, nanoVNA-F, and N1201SA units. The N1201SA is much better performance then nano's for S11 measurement. N1201SA at 1 GHz has about 50 dB dynamic range where the nano's are lucky to get 30 dB. Number on Z readout on N1201SA is much more stable and doesn't jump around like nano's.

The main difference in the N1201SA with its ADF4351 synthesizer is providing fundamental Tx signal where the nano's using the Si5351B must rely on harmonics for Tx above 300 MHz. Both use harmonic LO downmixer with the SA612 mixer.

I looked up specs for the synthesizer chips and the jitter for the Si5351B is very poor. The ADF4351(or ADF4350) is very good. The Si5351 is between 70 and 100 ps of jitter where the ADF4351 is less then 0.5 ps. That is a dramatic difference. The Tx jitter and Rx jitter are mostly independent since they are different dividers so their jitter stacks up to make things worse.

This impacts the dynamic range. The jitter at harmonics on the nano's is likely so bad that it is 'fuzzing up' the 5 KHz downconversion output to the point that it impacts the ability to measure the signal accurately.

There may be other factors such as if and how any smoothing averaging may being done or even layout/power supply noise differences. I am going to look at the Tx signals on spectrum analyzer on both units.

Measured 50 Ohm and 75 Ohm, the results were pleasing.
I'll tell you how-
The CH0 channel in Format is REAL and the CH1 channel is SMITH, the frequency is set to 50 kHz-10 MHz.
I connect the line to CH0 and at the end of the line I hook a variable carbon resistor with linearity A 470ohm. Slowly rotate the thread from maximum resistance until the Real line becomes perfectly flat. We look at the resistance readings - this is the resistance of the line. At 50 ohms, it practically lies on the center line, at the 75th it goes higher, just like in the Smith diagrams.
Meryl cables 75 and 50 ohm - an absolute coincidence in resistance.
On the screen, a piece of cable 1 meter of 75 ohm with two adapters of 50 ohms each showed a total resistance of 71.5 ohms.

A feature suggestion: Is it possible to get a delay in picoseconds directly from TDR. That would make it easier to get a starting point. I tried several values from 200ps to 50000ps and did not get a anything sensible on the Smith chart. I hoped to see a dot.
Earlier I noticed there are no impedances in polar form, that is magnitude<phase angle. There is no angle character in my keyboard.

Anyway, I use always nanovna_saver with a pc. Thank you.

Greetings, struggling with the nanovna-saver software for linux mint 19.3 mate for over a week now.I am definitely not a linux guru by any means, more like a semi dummy.
following the instructions at github.com/mihtjel/nanovna-saver I believe i have all the dependence satisfied.
When I run the pip installation python3.7 -m pip install . this the error baffling my poor head.
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-s_o_dw26/PyQt5/
Tried --upgrade pip etc.
Formatted HD, re installed Linux 19.3 Mate I have tried everything I can think of.
If anyone can point and old dummy like me in the right direction please don't be shy.
Laptop is Gateway NV53 64 bit by the way.

Thanks Jim KC2DHU

On Fri, Nov 22, 2019 at 08:22 AM, Dr. David Kirkby, Kirkby Microwave Ltd wrote:

Any male short standard would be nothing like 180 degrees. So the lack of a
properly implemented calibration routine would cause *very significant
errors* with the N connector.

Could this be resolved by using a proper (read: not cheap) N cal kit?

If N connector is only an option and not forced on all users, it seems to me that it would be acceptable to expect the user who wants it to fork for the proper cal kit, at least until the proper cal routines are developed. Since that would be only software, it can be done at a later date.

I am not sure how one is supposed to calibrate a VNA without a cal kit anyways. Simply having the option of simulating an open by not having anything connected to the instrument in the best case only solves the open issue. You still need the short and the 50 Ohm.

Hans, DJ7BA wrote: Anyone interested in more detail of (b), is invited to ask me for the derivation of (b).

Hans, because of real world losses, in a system with only one matching network, instead of a lossless system-wide conjugate match we can only have a conjugate match at a single reference plane. In most amateur systems, the matching plane is located at the Z0-match at the tuner input. My question is: Given that maximum power transfer occurs at the conjugate match reference plane, in a typical amateur radio system, where should that matching plane be located? (1) At the tuner input, (2) At the antenna feedpoint, (3) Somewhere else

Hello, Bo,
You will probably agree with me that only odd multiples of the fundamental frequency can be used for our measurements. They have amplitudes much higher than the even ones. I beg you not to create any further confusion, especially since many beginners are reading this.
I have worked on the further development of the EU1KY analyser and know what I am talking about.
73, Wolfgang, DH1AKF

I also just ordered the 4" nano using PayPal

73

Glen K4KV

Hi

In this old message I posted some pictures of the Si5351A output as the fundamental frequency approaches 300 MHz:
/g/nanovna-users/message/3285?p=,,,50,0,0,0::Created,,pll,50,2,0,34315096

A clarification of the clarification :-) The Si5351A does indeed outputs odd harmonics but also even ones and spurious too.

Bo

Thank you. I did not notice it at first. There was a discussion about Vna_saver 0.21 which didn't look very interesting at first, but there was info about this. I should have read it first