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Hi Jim

Those are the phase noise that you have on the open channel 1, nothing wrong.

If you only use it for S11 measurements, you may want to change all 4 channels over to Ch0
Go to
Display - Trace - Select Trace 3 - back - Channel - select Ch0 - back - Format - SWR - back - Back

This will change the purple Trace 3 to an SWR graph on CH0


The
Regards

Just the title attracted me to this, ID'ing core material. I have nanovna
and other stuff, Keep it up! Retired from plants with kilobuck equipment
and just MFJ and bottom feeded test equipment.

Hi, i just purchased a nano vna and can't seem to get it working properly. When i ruen the unit on i get only what i can describe as noise on the screen. When i calibrate the unit, the screen does not go blank but continues to display the noise. Ive tried resetting the unit but that did not help. Am i doing something wrongbor di I have a defective unit ? See the attachment for a photo. JIM NB3P

Hi,

I have same problem, my ultra portable laptop 32 bit only w10.

Lajos

Hi
Loaded on Win10 64bit S-a-a V2.2 latest firmware, will crash and close every time an 'Apply' command is requested ( when calibrating or trying to load a .cal file from version 0.3.5)
Version 0.3.5 will calibrate and run (has some 'jumps' or artifacts on the display)
I know it is a beta (pre) but want to try and isolate what part of the system is causing the crash.

TIA de Joe

Hello Group,

Yes I know that this has been pretty fully dealt with before and I have read all the posts but I still can't get a consistently good result.

The method that I used was to tightly wrap a single turn of 24 swg wire around the core (or 1 turn looped through the balun core) and soldered with minimum lead length to an sma female connector and run an S11 R/w & X/w. I tested on a range of type 43 cores and the FT50-43 and BN43-202 matched well plus the X = R crossover came out where I expected but the others came out widely different and seemed to give results more like I would expect from type 61 material.

I also experimented with an FT240-43 core and could not get the X and R lines to crossover with 1 turn at all so I tried 2 turns and got a crossover at around 80 MHz and 3 turns at about 25 MHz (going from memory here as I didn't screenshot this) so I am missing something entirely I think. I will look into Jeff Anderson's work and see if there is a better approach that I can make but it means that I will need to come to grips with matlab which I have not done up til now so there will be a time delay until I get some results.

Naturally I am hoping that someone will come up with "Hey Graeme, you didn't do this" as I am feeling that there is more that I have not done like maybe a low inductance copper tape around the core or something.

73, Graeme ZL2APV

As Thomas has noted, it's actually not difficult at all, following the design invented by Joe Dunsmore at HP, and implemented since in almost every broad-band VNA. I've seen a paper with a version that worked well from 100KHz to past 11GHz.

I've published the excerpt of Dunsmore's original publication here

This coupler works at high frequencies as a TLT (Transmission Line Transformer) built using coax or hardline, and at lower frequencies as a common mode choke. Dunsmore suggests using low-permeability high-frequency ferrites first, followed by high-permeability low-frequency ferrites. So there are three different effects at play here which all pan out to very broadband performance. The low frequency performance depends on the amount and permeability of the ferrite used. It fails at low frequency because the inductance is too low so the 50R impedance does not match the opposite leg of the bridge.

Dunsmore suggests an assymetrical bridge (same ratio, different impedances on two sides) to reduce through loss to 1.6dB, but Paul McMahon VK3DIP realised that a 6dB equal-arm bridge can use ferrite also in the corresponding arm, and that improves low frequency performance by a factor of 10. The VK3DIP design was copied by a German, which was copied in the Ukraine and then cloned (badly) in China, so you can buy the following product on EBay and Aliexpress. Although it is non-functional as shipped, it is easy to repair it to function as VK3DIP's intent, and with good semi-rigid cable trimmed properly and better resistors, it functions quite well from 100Hz through 3GHz. Still better than 20dB directivity at 2.4GHz:

transverters-store was the Ukraine company, now defunct. The fault with the Chinese clone is that one pair of 100R resistors are not joined at both ends to form a single 50R. I have test data on the stepwise improvements we made to one of these, and the final result. The 3GHz limit is due to poor trace impedance management and the large resistors being used. Just going to 0402 precision 50R resistors on a proper impedance-controlled PCB should get this up to 8 or 10GHz.

Gary,
Most of the developers have GitHub repositories you can grab a release from.?
Have a quick look at my search note at the top of the Wiki page and note how to search for a user's messages. Search for DiSlord's posts and look for the file attachment icon to see if there is firmware attached to a given post.?

... Larry


On Mon, 13 Jul 2020 at 7:19 PM, gary.sewell@...<gary.sewell@...> wrote: I have followed many threads here about new firmware releases from different developers and it is getting harder and harder to find the new builds. I see that Dislord has released a new build but I be damned if I can find it. I have looked through 191 posts in the thread and found nothing. Can we just post them in a new folder? Through venting ?

Hoger,

I am using NanoVNA Saver 3.4 and found a bug with Touchstone file export. There is a formatting bug that prevents the file from being loaded into other programs. It has to do with the Option Line. You specify the frequency in HZ and that is not valid. It must be Hz (z is lower case).

I attached an excerpt from the Touchstone specification for you.

Regards - Roger

I have followed many threads here about new firmware releases from different developers and it is getting harder and harder to find the new builds. I see that Dislord has released a new build but I be damned if I can find it. I have looked through 191 posts in the thread and found nothing. Can we just post them in a new folder? Through venting ?

Do you want us to test it DisLord? I can flash it on my H4.

Cheers!

FWIW, I have a commercial low-power directional coupler, -20dB coupling, that covers an amazingly wide frequency range.? I don't have it with me at this time, but as I recall, it's low tens of kHz up to a GHz or so.? I was curious how they got such a wide range; it's basically a resistive bridge with lots of ferrite around a coaxial line to allow all three ports to share the same ground.

Cheers,
Tom - K7ITM
----------------
"Weird hou men maun aye be makin war insteid o
things they need." -- Tom Scott (1918-1995)

Hi,

I have windows 10 32 bits... and I can't run these latest versions of
NanoVna Saver that are in 64 bits...

Does anyone know if they'll compile in a 32-bit version? Or another solution
?

Version 0.2.2-1 works fine on 32-bit

73

Enrique LU8EFF



--
El software de antivirus Avast ha analizado este correo electrónico en busca de virus.

Updated UI on H4
Screenshots
For H version see /g/nanovna-users/message/15203

I'm using Python to plot S11, S21, and group delay already... that would work well to open the serial port and pull the data directly in!

Thanks,
Brian

On Mon, Jul 13, 2020 at 10:02 PM, DiSlord wrote:

Some si5351 chips can non stable work at 300Mhz (on datasheet max 200MHz)

Tru reduce it maximum by set 290-301MHz:
'threshold 301000000' and wait result
if not help reduce
'threshold 299000000' and so on

Thanks for the hint and for your great work! While being a big fan of overclocking :) :) before reducing the max freq of the 5351 I started with downgrading the fw - tried v0846 with the same issue, now while testing the v0845 it looks stable so far. But it could be it gets more stable due to opened windows and fresh breeze in my hamshack :)
PS: increasing the 5351's core voltage may help with its stability at higher frequencies, imho..

First UI fixes
Rewrite some UI functions and logic
Implement advanced button configuration
Add buttin icons for checkbox and radio button

Use some UI ideas from OneOfEleven mod, but try not use flash for it, at result all of this not increase firmware size (less 70 bytes).

Next fixes possible allow custom text on buttons.

Here is UI example screenshots

On Mon, Jul 13, 2020 at 06:10 PM, OneOfEleven wrote:

It would be very easy to create a new serial command line to read the s-params
from the saved files and send them to the PC in the same format as it
currently does when sweeping.

You could add a serial command to list the available files, and a serial
command to read and send a chosen s-param file to the PC in normal serial
format.

Very interesting!!! It would be great to access the SD card via USB connection. Very good!

It would be very easy to create a new serial command line to read the s-params from the saved files and send them to the PC in the same format as it currently does when sweeping.

You could add a serial command to list the available files, and a serial command to read and send a chosen s-param file to the PC in normal serial format.

On Sunday 12 July 2020 04:32:00 am Gyula Molnar wrote:

Hi,
You can also visit this website about ferrites:


The first ferrite measurements with nanoVNA were discussed by forum members here: /g/nanovna-users/message/6996 and in subsequent discussions. (/g/nanovna-users/topic/nanovna_saver_0_2_0/54247421?p=Created,,,20,1,20,0&jump=1)

73, Gyula HA3HZ

Wow. Lots of good info there to digest... :-)

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin