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I've done a bit of searching through the past messages, but haven't found what I'm looking for....

I've recently updated my unit to DiSlord's v1.0.69, and there are a lot of interesting new features. What I am looking for is - has anyone put together, or knows where to find, a usage guide or set of recommended guidelines for the use of the new Marker>Measure features? Specifically, the L/C MATCH, CABLE, SHUNT LC, SERIES LC and SERIES XTAL functions? Any guidelines or typical use cases would be welcome.

Alan,
Would a simple google search help?
Looks like there's useful info.
Also - have a look over at eevblog.com - lots of good info in the various forums and a number of their members also lurk in the Nanovna forum(s).
You haven't said what model of device you're using - if it's an SAA unit, you may have problems as the output is not CW - there's talk about that in various messages.

also, have a look here: /g/nanovna-users/message/20788

Thanks Larry. The google result doesn't seem to come up with anything *specific* about how DiSlord's implementation of these measurements are intended to be used. And the second link which points to a video on making XTAL measurements is actually *MY* video on the topic.

Alan, I love your videos, some of the best, and I have learned so much from them!

I did some work attempting to measure crystals with the original Nano.





Of course, it's covered in the manual.

Specifically, the L/C MATCH, CABLE, SHUNT LC, SERIES LC and SERIES XTAL functions? Any guidelines or typical use cases would be welcome.

CABLE - this cable measure util, need calibrate nanoVNA and connect cable (there should be nothing on the other end of the cable)
NanoVNA measure cable wave impedance, length (need setup correct velocity factor) and cable lost in marker position (this just S11 logmag / 2)
wave impedance measured - search first frequency then it rotate on 180 degree, divide this frequency on 2 and measure reactance at this point.

L/C mathc calculate how convert impedance at marker position to 50 Om, suggest up to 4 solution how connect SRC SHUNT (L or C), SERIES (L or C) and LOAD SHUNT (L or C)

SHUNT LC, SERIES LC and SERIES XTAL - this improved port of this (need translate)
Also read this SERIES XTAL used for measure XTAL


i use Phase Shift Method, need only setup NanoVNA frequency range for see both resonsnce (see attachment)
And setup crystal connection R (for NanoVNA = 50Om, if used rystal Measuring Adapter as on link need set 12.5Om)

Nano Search phase shift (use interpolation, this allow get good results on low point count or on big frequency range)

Also i write on this forum (need translate from Russian):
Cable measure and renorm




DISPLAY->PORT Z option, used for measure different from 50Om load on NanoVNA, example need measure 75Om load, need calibrate NanoVNA as before on 50Om, and setup PORT Z = 75Om, NanoVNA recalculate measured result for this


XTAL measure

Hello DiSlord,

Thank you! This is exactly the information I was looking for! I appreciate your response and your excellent NanoVNA firmware work. I updated all three of my units (H4, SAA2N and V2plus4).

With Appreciation,
Alan W2AEW

You use my fw on V2Plus4? In v1.1 i extend points count to 401 and port all features from H/H4 (all V2 models), XTAL measure not work on V2Plus4 (you not see correct measure on display). Measure on SAA2N work, but can give errors

PS new V2Plus4 use different LCD and my fw not work, need use last fw version from nanorfe.com

This is great info, Dislord. Many thanks for your continued support.

John, wa3jrs

I am just finding this info about the V2plus4 and it’s locked down boatloader and fw author not willing to add ability to disable temperature compensation when CW mode is selected.

So is there no hope other than to try and buy a different V2 variant and sell this one ?

On Tue, Nov 30, 2021 at 04:15 PM, Larry Rothman wrote:

Would a simple google search help?
Invoking this search yielded /this/ thread as #3 from the top! So I guess it will take some scrambling...but for me, the question falls in 2 parts: How do we do these tests from a technical POV, and how to we use them in /this/ nVNA?

The first suggests to me that each of these measurements needs its own threads, here or elsewhere. And that is for each used who wants to do those specific types of measurements. The second, however, needs some explanation here. A basic setup. What to look for, what the display will show. For example, if I measure coax, does it /need/ to be short or open? What are some restrictions? VoP must be set (usually)? Frequency concerns? (That last one is subject to mythology, as several noted writers have stated "magical" formulas that a) are magical because there is no basis explained, and b) not really correct, as my tests show.) What /doesn't/ need to appear here, at least for my view of a user manual, are all the different ways we can use MEASURE > CABLE, and all the conditions for them. But we could easily start putting together an /applications/ manual that has all that in it.

My HP 15C is pretty basic compared to today's powerhouse calculators, but it came with a 300 page user manual and a 200 page advanced functions manual. Could I learn how to use that effectively? You bet. It is still a staple tool on my desk, on my tablet, on my desktop, and on my phone. I use it when I am flying, because it actually does weights and balances and wind correction angle calculations. To be fair, so does the E6BX app that I run on my tablet and phone. Not the point. I see so many questions about these nVNAs simply asking how to I use this? I started a user manual and am pretty much at a standstill, because I don't have access to experts who actually can answer my questions, but rather point to the web, and say do the research.
--
~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

On Wed, Dec 1, 2021 at 01:27 AM, DiSlord wrote:

CABLE - this cable measure util, need calibrate nanoVNA and connect cable
(there should be nothing on the other end of the cable)
NanoVNA measure cable wave impedance, length (need setup correct velocity
factor) and cable lost in marker position (this just S11 logmag / 2)
wave impedance measured - search first frequency then it rotate on 180 degree,
divide this frequency on 2 and measure reactance at this point.

1.2.5.3 CABLE S11
Choose a frequency range such that the cable length is ~1/4 of the wavelength in the middle of the range. This feature uses velocity of propagation. It automatically measures the length, characteristic impedance, and loss at the point of the active marker. Choose the range so that the Smith trace crosses near R=0 between ±j. The shorter the cable, the higher the frequency range needed for analysis. Example: Assuming the signal must go out and back on a 10 m length of coax, multiply c * VoP and divide by 4X the coax length. (3e8 m/s * 0.67) / 40m ~= 5 MHz. A range of 5-15 MHz would cover this.

This is what I am attempting to do with the user manual. There are many other ways to use this feature, but this addresses the basic requirements. Theoretically, any licensed ham will be able to adapt this description to other activities.
--
~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

On 5/3/22 6:26 AM, Rich NE1EE wrote:

On Wed, Dec 1, 2021 at 01:27 AM, DiSlord wrote:

CABLE - this cable measure util, need calibrate nanoVNA and connect cable
(there should be nothing on the other end of the cable)
NanoVNA measure cable wave impedance, length (need setup correct velocity
factor) and cable lost in marker position (this just S11 logmag / 2)
wave impedance measured - search first frequency then it rotate on 180 degree,
divide this frequency on 2 and measure reactance at this point.

1.2.5.3 CABLE S11
Choose a frequency range such that the cable length is ~1/4 of the wavelength in the middle of the range. This feature uses velocity of propagation. It automatically measures the length, characteristic impedance, and loss at the point of the active marker. Choose the range so that the Smith trace crosses near R=0 between ±j. The shorter the cable, the higher the frequency range needed for analysis. Example: Assuming the signal must go out and back on a 10 m length of coax, multiply c * VoP and divide by 4X the coax length. (3e8 m/s * 0.67) / 40m ~= 5 MHz. A range of 5-15 MHz would cover this.

This is what I am attempting to do with the user manual. There are many other ways to use this feature, but this addresses the basic requirements. Theoretically, any licensed ham will be able to adapt this description to other activities.

If you're writing a tutorial manual, then you should also address what happens if you use a cable that is, say, 3/4 wavelength.

On 5/3/22 6:16 AM, Rich NE1EE wrote:

On Tue, Nov 30, 2021 at 04:15 PM, Larry Rothman wrote:

Would a simple google search help?
Invoking this search yielded /this/ thread as #3 from the top! So I guess it will take some scrambling...but for me, the question falls in 2 parts: How do we do these tests from a technical POV, and how to we use them in /this/ nVNA?

The first suggests to me that each of these measurements needs its own threads, here or elsewhere. And that is for each used who wants to do those specific types of measurements. The second, however, needs some explanation here. A basic setup. What to look for, what the display will show. For example, if I measure coax, does it /need/ to be short or open? What are some restrictions? VoP must be set (usually)?

The VNA has no way to know the relationship between physical length and electrical length. So you have to enter propagation velocity.? In a tutorial, since it has come up, one might have an explanation of how to measure the propagation velocity.

Frequency concerns? (That last one is subject to mythology, as several noted writers have stated "magical" formulas that a) are magical because there is no basis explained, and b) not really correct, as my tests show.)

The effect is real, but small. The formula is the Telegrapher's Equation, which describes the propagation of a wave in a transmission line in terms of L,C,G, and R.? These all vary somewhat with frequency, most notably G and R (due to skin effect and dielectric losses, which vary with frequency).? The basis, if one needs it, is found in pretty much any textbook that covers transmission lines.? Search for "lossy transmission line" and once you get past the basics of loss, then the full equation is introduced.

Perhaps the transmission lines you have tested don't have sufficient variation in G and R with frequency to show the difference, but dispersion certainly exists.


Prof. Orfanidis at Rutgers has his textbook online, although I'm not super wild about his transmission line section, it does cover all this. One of the nice things is that he has published Matlab routines for a lot of useful stuff

What /doesn't/ need to appear here, at least for my view of a user manual, are all the different ways we can use MEASURE > CABLE, and all the conditions for them. But we could easily start putting together an /applications/ manual that has all that in it.

My HP 15C is pretty basic compared to today's powerhouse calculators, but it came with a 300 page user manual and a 200 page advanced functions manual. Could I learn how to use that effectively? You bet. It is still a staple tool on my desk, on my tablet, on my desktop, and on my phone. I use it when I am flying, because it actually does weights and balances and wind correction angle calculations. To be fair, so does the E6BX app that I run on my tablet and phone. Not the point. I see so many questions about these nVNAs simply asking how to I use this? I started a user manual and am pretty much at a standstill, because I don't have access to experts who actually can answer my questions, but rather point to the web, and say do the research.

This kind of gets to a point - there *are* people who know the answers on this list, but in general, they also have other things to do, so their time is limited. It's great that you're taking on the challenge of writing a book to explain it, but as you know, it's time consuming.

To be honest, a threaded list isn't the best way to explain this kind of thing. The person who wrote the software generally has a good understanding of the theory, but doesn't necessarily have the time to answer it in a 20 questions form, and, it's also possible to be knowledgeable for writing the code, but not such a great explainer.

When it comes to some topics, too, it is very difficult to explain the subtleties and variations without some background knowledge, which takes time to acquire. A good example is antennas. Everyone knows the "dipole length" formula, but to explain why it's not exactly a half wavelength is a MUCH more complex issue.?? Facile answers like "end effects" or "empirically discovered constants" don't really explain it.

On 2022-05-03 06:29:-0700, you wrote:

If you're writing a tutorial manual,

I'm not. I'm writing a user manual for the nVNA. I think we could all benefit from tutorials of some sort, but we all have different interests. To me, that means that many people would prepare tutorials, each in their own area of interest or knowledge.

When I first saw CABLE, I didn't know what would happen when I selected it. Now that I know, I can try to use it in different ways.

~R~

On 2022-05-03 06:45:-0700, you wrote:

This kind of gets to a point - there *are* people who know the answers on this list, but in general, they also have other things to do, so their time is limited. It's great that you're taking on the challenge of writing a book to explain it, but as you know, it's time consuming.

To be honest, a threaded list isn't the best way to explain this kind of thing. The person who wrote the software generally has a good understanding of the theory, but doesn't necessarily have the time to answer it in a 20 questions form, and, it's also possible to be knowledgeable for writing the code, but not such a great explainer.

This gets to the heart of the matter.

there *are* people who know the answers on this list, but in general, they also have other things to do

Good for them. So do I.

It's great that you're taking on the challenge of writing a book to explain it, but as you know, it's time consuming.

All I set out to do is write a user manual for the nVNAs (-H and -H4, though it generally applies to other nVNAs). I figure that if I write down each feature as I learn it, then that will benefit hundreds? thousands? of those to come. Oh, wait, there are already people who know all this, and could have taken 30 minutes to think about the device and jot down some useful things that they know.

I have long history with software engineering. That means writing requirements, a design, then software and software testing. We don't seem to have much of this. I created the menu map in yEd because it is readily accessible, and anyone can update it from here out. So we have a Russian hacker who creates this stuff. I'm impressed with the talent. I don't speak Russian as well as he speaks English, and that is not very well. What I set out to do is write down what I think will help others new to the technology know what will happen when they press a button. That's why I posted that excerpt, to show what my intent was. I say was, because it didn't take long to exhaust resources. So, since I don't intend to spend hundreds of hours learning all this stuff, and there is not much feedback besides "look it up on the web", I figure /this/ part of the project is stalled.

I've created lots of requirement docs in the past. Lots of design docs in the past. Lots of programming and software testing. So it's not that I don't get it...I do.

it's also possible to be knowledgeable for writing the code, but not such a great explainer.

This is a good point. But for me, it's a show-stopper. Because when I ask a question, and there is no answer, there is nothing to write down. I assume that no one actually understands what the answer is. I've put the user manual aside. Maybe all that I want to know is there in Russian, but that does me no good. I certainly don't fault a Russian for writing in Russian. I actually started learning Russian years ago, because I thought of them as major players in the science field. But then most of the people I worked with spoke pretty good English...not great, but we could have a conversation, and I could connect the dots. So I stopped learning Russian. Rats. Well, too late to start now...

BTW, this discussion is not limited to this device. I spent 10 years working with PhDs who had the same lazy attitude. Too busy getting ahead of the next PhD to write down what they were doing. Before I left that group, they had hired //another// PhD to work in the lab ///// to reconstruct what had happened 10 years earlier /// because they were too lazy to write it down, and then had the misfortune to need it.

I agree that we all get to choose how we spend our time. The scarcity of information is actually a time-saver for me.

~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

On Tue, May 3, 2022 at 06:41 PM, Rich NE1EE wrote:

it's also possible to be knowledgeable for writing the code, but not such
a great explainer.

This is a good point. But for me, it's a show-stopper. Because when I ask a
question, and there is no answer, there is nothing to write down. I assume
that no one actually understands what the answer is. I've put the user manual
aside. Maybe all that I want to know is there in Russian, but that does me no
good. I certainly don't fault a Russian for writing in Russian. I actually
started learning Russian years ago, because I thought of them as major players
in the science field. But then most of the people I worked with spoke pretty
good English...not great, but we could have a conversation, and I could
connect the dots. So I stopped learning Russian. Rats. Well, too late to start
now...

BTW, this discussion is not limited to this device. I spent 10 years working
with PhDs who had the same lazy attitude. Too busy getting ahead of the next
PhD to write down what they were doing. Before I left that group, they had
hired //another// PhD to work in the lab ///// to reconstruct what had
happened 10 years earlier /// because they were too lazy to write it down, and
then had the misfortune to need it.

I agree that we all get to choose how we spend our time. The scarcity of
information is actually a time-saver for me.

May I say that explaining somethings is very hard. There is an optimum length of explanations, but there will always be questions. I have some 20 years of experience in explaining things, and what ever I said, there was always some one who had questions.

On 5/3/22 8:10 AM, Rich NE1EE wrote:

On 2022-05-03 06:29:-0700, you wrote:

If you're writing a tutorial manual,

I'm not. I'm writing a user manual for the nVNA. I think we could all benefit from tutorials of some sort, but we all have different interests. To me, that means that many people would prepare tutorials, each in their own area of interest or knowledge.

To a certain extent, though, a user manual is tutorial in nature, if you're giving step by step procedures for how to execute some measurement.? Perhaps not to explain the background, but surely we want something more than a "man file" which lists the available options with no information on why you might want to use it.