开云体育

Hi w3wtw,
Several solutions are possible.
The easiest is to wear glasses.
Last year, when development was in its infancy, there was firmware that used larger letters. Then during development, it was lost because the firmware of the processor used (I’m talking about nanoVNA -H, which is 2.8 ”screen size) included many features that made uppercase letters on the small screen impossible.
You have the option to buy a larger screen device (4 ") or use a PC program that also manages the small device from the computer side.
One of the best (if not the best) of these programs is NanoVNA-App v1.1.206 by OneOfEleven , tested and released for beta use by a beta development team. This program works with DiSlord-enhanced firmware version 1.0.45. The PC program can be used on Windows XP-7-10.
The firmware is 2.8 - 4 " can be installed on NanoVNA with a size display.
Another option is a previously developed NanoVNA Saver developed by Rune, 5Q5R up to version 0.2.2.1, the current version is 0.3.8, which runs on Windows7-10.
There is NanoVNA Partner v0.20, which also works well on Windows XP.
Read more about my options on my web page (see last line).
So it is advisable to install the latest firmware to work with PC programs.
I hope I helped with the solution.

73, Gyula HA3HZ
--
*** If you are not part of the solution, then you are the problem. ( ) ***

Dear Gyula,

thanks for the goal-oriented hint ... now everything works fine!!

Best 73s de DL6RDE, Charlie

-----Ursprüngliche Nachricht-----
Von: [email protected] <[email protected]> Im Auftrag von Gyula Molnar
Gesendet: Sonntag, 21. Februar 2021 11:50
An: [email protected]
Betreff: Re: [nanovna-users] Problem with NanoVNA Saver 0.2.2.1

Hi Charlie,

I think there is only a shortcoming in the use of the program.
When you want to measure something and have already drawn the graph, you can make the measurement data visible with the markers.
Displaying the markers: you select with the mouse, by default the marker1, then you click with the mouse again on the graph, then the measurement data is displayed. Then select the next marker and the graph will display the desired frequency data where you have been missing so far.
You may want to search the group wiki and files folder to use nanovna-saver and you will get many questions answered.
Successful use.
Don't give up, this version can also be used!

73, Gyula HA3HZ
--
*** If you are not part of the solution, then you are the problem. ( ) ***

Hi Charlie,

I think there is only a shortcoming in the use of the program.
When you want to measure something and have already drawn the graph, you can make the measurement data visible with the markers.
Displaying the markers: you select with the mouse, by default the marker1, then you click with the mouse again on the graph, then the measurement data is displayed. Then select the next marker and the graph will display the desired frequency data where you have been missing so far.
You may want to search the group wiki and files folder to use nanovna-saver and you will get many questions answered.
Successful use.
Don't give up, this version can also be used!

73, Gyula HA3HZ
--
*** If you are not part of the solution, then you are the problem. ( ) ***

Hi, new user so thanks for your patience.

Calibrated and confirmed appropriate procedure per reference videos.
Did a wide sweep, and then resonant sweeps for two different triband antennas and found: good VSWR for two bands (~1.2:1 , high VSWR (±5:1) for other two bands, both antennas on different bands (one was high on 75cm, the other 220(?)). So two different bands had one high SWR, and two low SWR readings on _different bands_. (Comet vs. Fong)

Would the reason be calibration, normal, or user error? Thanks!

hugen has recently released a version of DiSlord's v1.0.45, with larger font, for H & H4 (with a few other changes too):



Not sure if this helps?

Is there a capability to control the tone used in the sweep or CW? Iv been using it as a tone generator, but I'd like to be able to control the tone freq and level.

Thanks a ton,

John

Roger:

I very much like the S11 phase vs impedance phase chart you did up for us. This sure makes the difference easy to understand :-)

Following along...

--
VE6WGM

I am happy with where this thread has gone. The information is excellent and clearly laid out, and did not digress into anarchy and mayhem :-)

Thank you Roger (and others).

If anyone observes any technical errors in any of the nanoVNA videos I have shared, please let me know. I will accept the feedback and correct the errors.

--
VE6WGM

This next post is about measuring inductors and self-resonance. I have an old multi-layer choke in my junk box and I measured it with the NanoVNA. My goal is to post some graphs of the results and explain some of the observations and pitfalls for those new to measuring components with the NanoVNA. For larger components I use a double banana jack to BNC test jig. I find it works fairly well but the effects of parasitic capacitance/inductance and impedance bumps limits it to about 60 MHz. A photo is attached which shows the configuration and how the cal loads are constructed. The cal loads are made from double sided FR4 PCB stock with conductive adhesive copper foil used to connect the top and bottom layers. The foil is also soldered in a few places. A 49.9 ohm 0805 SMD resistor is used for the 50 ohm load.

To show how well this jig works I have attached a measurement of a 1K SMD resistor soldered to one of these test boards. The measurement is within 12 ohms which is quite good considering the magnitude of the reflection coefficient is very close to 1.

A photo is attached of the inductor used and includes a simplified model of a typical inductor . I measured it with a DE-5000 LCR meter and at 100 kHz. it was 653 uH with a series resistance of 23 Ohms. The NanoVNA measured 660 uH and 23 which is very close.

A series of graphs are attached. Self capacitance due to the multi-layer winding results in self resonant frequency of 4.627 MHz. At this point the inductance and capacitance of this parallel resonant circuit cancel out and we see a high resistance measured by the NanoVNA. The NanoVNA is not very accurate at measuring resistances beyond 1 or 2K so we cannot rely on the actual number (we only know that its large). If we want to get a better estimate we can use the S21 series method but that is a topic unto itself.

From the graph one might assume that the inductance is changing as we approach resonance. This is not the case and is due to the way the software calculates inductance using L = X/(2*pi*freq). X is increasing at a faster rate than L alone because of the parallel capacitance in the circuit. Some authors refer to this as "apparent inductance" as opposed to "actual inductance" and there are methods to calculate the actual inductance vs frequency.

The last two graphs show "S11 phase" (or reflection coefficient phase) and "impedance phase" versus frequency. There was some interest in previous posts on this topic so I have plotted both for comparison. The impedance phase was calculated by exporting a s11 Touchstone file to a spreadsheet where it could be calculated and plotted. Note that both have zero phase at resonance but are completely different at other frequencies. Roger

Hi Roger et al,

Ooooppppssss .... I think I blindly stepped into something .... or 'stepped onto' something ... :)

I guess it is going to take me awhile to understand that issue .... and the shape of that S11 Freq Phase graph.

Maybe some differences of opinions but great info for people like me. I have found that a lot of differences between experts usually comes down to definitions/terminology.
--
Cheers,
Ian
Melbourne, Australia

Roger-

Your latest message very clearly described the differences between a reflection coefficient phase angle and the phase angle associated with a complex impedance.

Sounds like most of the recent responders are in violent agreement.

Regards,

-Ray
WB6TPU

You are using an ancient version, see if it is the same
with the recent one.

On Sat, 20 Feb 2021 at 21:21, Karl-Heinz Merscher <
karlheinz.merscher@...> wrote:

Hello,



I recently have problems to display Marker 1, Marker 2, Marker 3 and so on
.

The graphs are shown but I miss the Marker 1, Marker 2, Marker 3 . values
(see yellow colour)



Anybody out there who can help me .



Thank you so much.



Best 73s de DL6RDE, Charlie

Roger, you are indeed correct. I also appreciated Arie's comment. Gregg is
also correct for the reflected signal measurement - and in saying that this
is related to the V/I/phase in the DUT; indeed since the VNA is providing
the signal to the DUT, all V/I/phase in the DUT and those reflected will be
related - but that relationship is complex. S11 does not measure the
device itself, it measures the reflection that device causes in the
feedline between the VNA and the device. (An S21 measurement will measure
some characteristics of the device itself.)

A very simple example of this is when the DUT is an antenna. The VNA S11
is a measurement of the reflected signal in the feedline, and ideally we
design this to be a perfect match at 50 ohms purely resistive, which will
have a reflected phase angle of 0. But the V/I/phase in the antenna itself
varies greatly along the antenna, and the phase is necessarily non-zero
except at the feedpoint.

On Sat, Feb 20, 2021 at 11:14 AM Roger Need via groups.io <sailtamarack=
[email protected]> wrote:

On Sat, Feb 20, 2021 at 01:21 AM, Arie Kleingeld PA3A wrote:

Maybe the misunderstanding is in the fact that the reflectioncoefficient
has another phaseangle than the phaseangle between current and voltage
on the load. These are two different things. The relation is in the
already quoted formula.

Arie,

Thank you for your comment. That is exactly the misunderstanding I was
referring to in my previous post. I am also on Facebook and I have seen
several posts there that stated that the "S11 phase angle" displayed on the
NanoVNA and the "impedance phase angle" of the device under test were the
same thing. Several YouTube videos have also made the same assertion which
is wrong and confuses those new to this subject. That is why I stated the
following in one of my drawings in the post above....

"This is the S11 phase plot which is the angle of the reflection
coefficient gamma. A common misconception by those new to S parameters is
to confuse this with the impedance phase of the device under test (DUT)"

I do not see why some object to this statement which is all I said on this
subject. I will write another post later today to clarify why this is true.

Roger

Roger

Hello,



I recently have problems to display Marker 1, Marker 2, Marker 3 and so on .

The graphs are shown but I miss the Marker 1, Marker 2, Marker 3 . values
(see yellow colour)



Anybody out there who can help me .



Thank you so much.



Best 73s de DL6RDE, Charlie

This is a friendly group and I do not wish to get into some kind of argument with others. If I have posted something in this group which is wrong or confusing please quote what I said and tell me why it is incorrect and I will do my best to answer your question or if proven wrong admit my error. But please quote what I said NOT what someone else thought I said or meant about the subject at hand.

In a previous post on a graph I wrote "This is the S11 phase plot which is the angle of the reflection coefficient gamma. A common misconception by those new to S parameters is to confuse this with the impedance phase of the device under test (DUT)". Here is why I believe that to be true.

If we have a complex impedance attached to our NanoVNA and wish to measure its characteristics we can do this with an S11 or S21 measurement. For the purposes of this discussion I will focus on the S11 measurement.

Let us say our device under test (DUT) consists of a 50 ohm resistor in series with a 1.6 uH inductor. We perform the measurement at 5 MHz. The inductive reactance is X = 2*pi*freq*L which is equal to 50 ohms. So the complex impedance R+jX is 50+j50. At 20 MHz. the same DUT will have a complex impedance of 50+j200.

It is well known that the "impedance phase angle" is equal to the arctangent of X/R and this will range between +90 degrees to -90 degrees depending on the values of X and R and whether X is inductive or capacitive. For the case of 50+j50 the phase angle is arctan 1 or 45 degrees and fro 50 + j200 is arctan 4 or 76 degrees. This is shown on the attached diagram. We could easily do a plot of impedance phase versus frequency for the DUT and get a graph.

Now when we connect this example DUT to the CH0 port of a NanoVNA and do a measurement over the range of 5 to 20 MHz. we can set the traces to display a number of parameter plots. One that is very useful is to plot the "reflection coefficient" Gamma (Γ) . Gamma Γ = (Z - Zo) / (Z + Zo) with Z being a complex number and Zo typically set at 50 or 75. Note that Gamma will also be a complex number in the form a+jb or as magnitude @ an angle. The Magnitude is = sqrt(a^2+b^2) and the angle is the arctan (b/a). The angle is often referred to as the "S11 phase angle" and that can be displayed on the NanoVNA or in PC programs that work with the PC. There are calculators that calculate the reflection coefficient in both forms for a given R and X and the phase angle . Here is one that is easy to use.



If R and X are plotted on a Smith chart the vector from the origin to that point will have a length equal to the magnitude of the refection coefficient and the angle will be the S11 phase angle. I have plotted the 50+j50 and 50+j200 on a Smith chart and attached them to this post.

Here is a comparison of the "impedance phase angle" and "reflection coefficient phase angle" for the two cases above. One can clearly see that they are different which is what I originally stated. Yes reactance does have an effect on both and this is not in dispute. But they are different measurements!

Impedance phase reflection coefficient phase
50+j50 45 63.4
50+j200 76 26.6

It would be nice if the "impedance phase angle" could be added to the graphing capability of the NanoVNA or one of the PC programs. Someone requested this on the NanoVNA saver GitHub page last month.

Roger

On Sat, Feb 20, 2021 at 01:21 AM, Arie Kleingeld PA3A wrote:

Maybe the misunderstanding is in the fact that the reflectioncoefficient
has another phaseangle than the phaseangle between current and voltage
on the load. These are two different things. The relation is in the
already quoted formula.

Arie,

Thank you for your comment. That is exactly the misunderstanding I was referring to in my previous post. I am also on Facebook and I have seen several posts there that stated that the "S11 phase angle" displayed on the NanoVNA and the "impedance phase angle" of the device under test were the same thing. Several YouTube videos have also made the same assertion which is wrong and confuses those new to this subject. That is why I stated the following in one of my drawings in the post above....

"This is the S11 phase plot which is the angle of the reflection coefficient gamma. A common misconception by those new to S parameters is to confuse this with the impedance phase of the device under test (DUT)"

I do not see why some object to this statement which is all I said on this subject. I will write another post later today to clarify why this is true.

Roger

Roger

Hi Manfred,
You note that you cannot use NanoVNA Saver under Windows XP.
I inherited a laptop running Windows XP from my daughter.
I just tried that if I copy the NanoVNA-App to the C: / root directory, it will log in without further ado.
I remembered that the creator of the program mentioned this, but I never tried it.
You may also want to update the firmware because the program and firmware were developed together.
So one cannot be used without the other.

--
*** If you are not part of the solution, then you are the problem. ( ) ***

I don't need to "prove" you wrong. Without phase, reactance just becomes a
non-dissipative circuit element that doesn't do much outside of resistive
losses. One can't have a reactive component without phase.

Z = R ± jX

Without phase information, there is no ± jX term and no reactive component.

Dave - W?LEV

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

If you explore NanoVNA-App you will find lots of things. Right click on the graph window to find numerous options. Clicking on the text in the upper left corner of the graph window will allow you to select the graph type. The New Graph button at the far right of the top button row will do just that.

Do upgrade your firmware. You will benefit from new features and bug fixes. I am using Dislord 1.0.45 on my H. There is no "standard" firmware, only latest and obsolete. :)

73

-Jim
NU0C


On Sat, 20 Feb 2021 06:33:06 -0800
"Manfred Mornhinweg" <manfred@...> wrote:

Roger,

The NanoVNA MOD v3 software has some nice plotting features but I prefer the
NanoVNA app by OneOfEleven that works with the 1.0.45 firmware by DiSlord.

I didn't know about that software. I just downloaded it, but it doesn't seem to work with standard firmware, and I'm hesitant about changing to a different firmware, given that the stock one works well.

Also, I didn't find a way to change what the graph displays. Is it really limited to only displaying S11 and S21? Among all the options given by the NanoVNA, and by the PC software I'm using, I find RLC graphs most useful for component testing.

The firmware does 401 points on the -H4 instead of 101, faster data
transmission and some nice new user features on the NanoVNA. The NanoVNA app
is the best PC program I have used to date with nice scaling and plotting
features, trace smoothing, calibration averaging and the ability to do
firmware updates and much more.

I only have the NanoVNA-H, and I wouldn't like to put special firmware on it. So it seems that the software you use is not for me!
I can't use NanoVNA Saver either, because it doesn't run on Windows XP, and that's what I use.
Good that there is a choice of programs.

I would love to get more than 101 points, and I would also love an actual RLC display, rather than the RXZ display given when selecting RLC. A true RLC display would be great to directly observe the variations of component values against frequency.

Maybe some day I end up writing my own program for this purpose. Is there a clear description of the NanoVNA's communication protocol?

That clothespin idea is really interesting for testing SMD parts. I am going
to build a jig using this method. If you have one already built could you
please post some pictures.?

I haven't built it yet. It's just an idea. So far I have only built that very simple component test jig using a small piece of PCB, using clothespins for calibration and for holding component leads and SMDs against the board. It serves me well enough for now.


Ray,

The use of a small piece of Teflon or other plastic between the contacts of the clothespin for doing the OPEN calibration may be a bit problematic.
It will increase the capacitance between the contacts which will probably lead to a less accurate calibration . I would suggest finding a way to hold
the contacts open without the inclusion of the plastic.

Well, there is no need to place the plastic "open" calibrator between the contacts! A clothespin jaws are much larger than an SMD. The jig could easily be made with small contact areas, something like 3mm diameter. The "open" calibrator can be placed in the clothespin several mm away from those contact areas. That should bring the "open" calibration error down to less than 0.1pF, which is probably good enough for most of us.

The traces leading to the contact areas should of course run well away from each other, to reduce capacitance miscalibration if the clothespin flexes and distorts in use.

Roger,

The NanoVNA MOD v3 software has some nice plotting features but I prefer the
NanoVNA app by OneOfEleven that works with the 1.0.45 firmware by DiSlord.

I didn't know about that software. I just downloaded it, but it doesn't seem to work with standard firmware, and I'm hesitant about changing to a different firmware, given that the stock one works well.

Also, I didn't find a way to change what the graph displays. Is it really limited to only displaying S11 and S21? Among all the options given by the NanoVNA, and by the PC software I'm using, I find RLC graphs most useful for component testing.

The firmware does 401 points on the -H4 instead of 101, faster data
transmission and some nice new user features on the NanoVNA. The NanoVNA app
is the best PC program I have used to date with nice scaling and plotting
features, trace smoothing, calibration averaging and the ability to do
firmware updates and much more.

I only have the NanoVNA-H, and I wouldn't like to put special firmware on it. So it seems that the software you use is not for me!
I can't use NanoVNA Saver either, because it doesn't run on Windows XP, and that's what I use.
Good that there is a choice of programs.

I would love to get more than 101 points, and I would also love an actual RLC display, rather than the RXZ display given when selecting RLC. A true RLC display would be great to directly observe the variations of component values against frequency.

Maybe some day I end up writing my own program for this purpose. Is there a clear description of the NanoVNA's communication protocol?

That clothespin idea is really interesting for testing SMD parts. I am going
to build a jig using this method. If you have one already built could you
please post some pictures.?

I haven't built it yet. It's just an idea. So far I have only built that very simple component test jig using a small piece of PCB, using clothespins for calibration and for holding component leads and SMDs against the board. It serves me well enough for now.


Ray,

The use of a small piece of Teflon or other plastic between the contacts of the clothespin for doing the OPEN calibration may be a bit problematic.
It will increase the capacitance between the contacts which will probably lead to a less accurate calibration . I would suggest finding a way to hold
the contacts open without the inclusion of the plastic.

Well, there is no need to place the plastic "open" calibrator between the contacts! A clothespin jaws are much larger than an SMD. The jig could easily be made with small contact areas, something like 3mm diameter. The "open" calibrator can be placed in the clothespin several mm away from those contact areas. That should bring the "open" calibration error down to less than 0.1pF, which is probably good enough for most of us.

The traces leading to the contact areas should of course run well away from each other, to reduce capacitance miscalibration if the clothespin flexes and distorts in use.