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On 16.10.2019 19:01, N9KDY wrote:

Not, "Is there?" but what are some of the more simple functions of this thing which might benefit beginning users, so that as I run into them I can perhaps write some?

That is great idea. Most people need nanoVNA for quite simple tasks.

That said, there are number of useful tutorials on YouTube. Listing them would also help new users.


--
73,
Pedja YT9TP

Checkout:

Oristo, I also ordered two if those, and a couple of 10 db attenuators. They look like a good test jig for experimenting with small components or transformers. I have one of the $9.00 eBay bridges, and a noise source. With a SDR as a detector I can do some Nano to Bridge comparisions, I hope.

KE8CPD6,

I had the same issue as you. After clearing the config data and recalibrate, it seems to work OK. Here is what I did.

- Plug in the USB
- Use putty or any terminal software to connect to NanoVNA
- At shell interface, type "clearconfig", then "saveconfig". This is equivalent to load "CLEAR_MEMORY_DFU.dfu".
- Redo calibration.

Larry Rothman wrote:

I use a hot air gun to loosen the parts.

I have a full surface-mount hot-air soldering system with a reasonably accurate temperature control and a set of half-a-dozen or so tips of various diameters. Tooling is not the problem.

Actually seeing 0402 size parts well enough to stick them on a circuit board in the correct place, well, now that is a problem.

Old age is not for the weak or timid.

I had considered modding a cable. Might be worth a try, rather than destroying a mostly-working piece of decent kit trying to solder on something I can't see any longer.

--
Wes Will
N9KDY

On 10/16/19 4:13 PM, n2msqrp wrote:

I hate paying ten bucks shipping for fifty
cents-worth of parts.

Well if you can stand the wait, ten bucks (in total) could get you a (small) boat load assortment of

sma resistors in maybe 30 +/- values (prob. 10-20 each) from China. Might as well grab some caps, too.


BTW love that little 4.3'' microscope! For sma work I prefer my binocular regular optical, but in

a pinch that thing might come in handy!


Bill

Hello again GIN & PEZ;

Your #51 full final report is a much improved compilation but as mentioned earlier, it is quite difficult to read and follow, much less comprehend, when it requires navigating through numerous links. This report answers some of my questions, and is helpful toward identifying questions that remain for this to be understood. Some of my questions may fall out as I digest this more; based on inferences borne out of my current sense of understanding. As such; I will summarize and then start with some of the more obvious questions needed to fill in some details as I digest more of what you have presented.

I believe you presented, in one of your earlier "final" posts, the raw data files used to generate the plots in your "full final". I was frustrated by not having a means to perceive or evaluate that data in my journey toward understanding what is being presented. To that end; I attempted to download and install the software you identified in an earlier post on this topic as an effort to replicate your results. This appeared to be the only means you were providing as a vehicle to our understanding. My attempt at this was abruptly terminated upon my discovery that the link you provided to your Fortran complier openwatcom-fortran][1.9] went dark a few years ago, and further research turned up on shadowed versions.

It should be obvious why this is a major issue, but I will explain why it is for me in order that you understand the magnitude of the handicap it presents and the disconnect we have with respect your intentions of presenting your project FACUPOV.

1) Fortran is a powerful programming language, and much high quality legacy code requires it (the compiler) to be supported to ensure that the legacy programs can be maintained and remain relevant. Your source dictates this.
2) Fortran comes in many forms, versions, etc., including the compiler you use or have been using. It must be made available in order to ensure that your source code compiles accurately as you intend it to compile.
3) Fortran source code is quite readable by most skilled programmers who, out of necessity, have become multi-lingual coders as a consequence of making programming their career. A few appear to be on this list.
4) Using any compiler to create an executable product from a source not written for it, as its native compiler and version, is likely going to yield errors. Some errors may be minor and easily corrected; some may require new code and/or structure changes; any and all of which will likely require a seasoned programmer. I may be a bit off of the mark on the following; but I don't believe Fortran is likely the language of choice taught to freshmen programmers recently.
5) FACUPOV; most seasoned RF designers, and many RF technicians are familiar with, and can hack at code in various programming languages; and their skill level may vary from novice to advanced. This may be a Common User asset, but their POV may be vastly different. Any derivative of your work will take on as many different forms as there are attempts made to get it up and running. You might even cringe at some of their craftsmanship, because their interpretation of your work doesn't quite pass muster.
6) Either attempting to work through the above while holding fast to the notion that the tasks will yield legitimate results, or writing independent software to manipulate and exercise your equations in a manner consistent with our very limited understanding thusfar, are both significant tasks, either of which are prone to misinterpretation, miscalculation, and false conclusions about what you wish for us to understand, and I trust you would agree that doing so if far beyond the expectations of being FACUPOV.

If I may suggest and recommend a relatively straight forward solution that may advance your progress, whether or not you are successful toward reaching your goal here.

I believe your requirements here can be fulfilled by the ambition and skill set of an undergrad, or freshman graduate studant.

As I described earlier; I think the entire process you describe in your final report can be coded into a single executable which then could be distributed to clients of interest to you. If I am incorrect in this assessment; it must be concluded that I remain far away from understanding your project. If your passion about your work that comes through in your writings is being correctly interpreted, then I would expect that you would concur such a task is both worthwhile and warranted.

You would first have to mentor the student on how each of the component modules interact, from data input to graphical output. Allow them to pursue the task of learning the Touchstone format as the desired format for the input data of the executable. This will greatly mobilize your ability to gather data from competing sources as test cases.

If you wish to maintain your automated data collection system as your own and ongoing source of input to the executable, the student could also be tasked to write a separate format conversion module in Fortran to ease the task of reducing the data it provides into a format compatable with the more universal Touchstone format used as input to the executable program.

It may be of further benefit to give the student the freedom of choice for the programming language used with the caveat that it needs to yield both a Windows and Linux version.

-
73

Gary, N3GO

The newly released NanoVNA-H has added the 5.1K Type-C CC resistors, which is already installed if it have a "NanoVNA-H V3.3" tag on your PCB.

Well, what is wrong with making a dedicated cable by cutting it, use a small elongated perf board (or etched board? wiring it one to one with the resistors on the board and heat shrinking it all back together?

Good Evening Everyone,
It looks like this thread has kinda died a bit. I am still without a fix for my issue. I tried again to updated the firmware this evening and still ran into issues above 300mhz. I calibrated it (see photo of correction turned on) and the photo of the version.

Anything beyond the 0.2.x firmware is causing the issues, since 0.1.1 works just fine. I have seen other people have similar issues with the new firmware on this group.

Unfortunate, it is a little more involved. However, some assumptions might be used and you can see how close you come. Given that the VNA with no added effort returns only S21 and S11.

The input power should be reduced. Try a 20 dB pad at the CH0 port. Takes Pin down to ~ -30 dBm. You will need to do a cal with attenuator in place.

As an approximation to h21, lets assume the device is matched at its output, hence S22=0. Not true, an assumption. Then |h21|= 2(s21)/(1-s11).

This takes S22 to zero and S12 to zero. Big assumptions but better than just using S21 alone to achieve a value for ft. Of course the driver here again, is without effort, the VNA returns s21 and s11. That's it. So running with that alone MAY get you in the ball park. It would be neat to run an analysis in LT Spice for a 2N3904 and return ft the correct way and then using the assumption above.

Note, the ft value of a transistor device assumes a simple one pole equivalent circuit. The main contributors to ft are device input capacitance and the device transconductance, gm. Although it is a useful quality of merit parameter it is not the only parameter and only partially explores the capability of a semiconductor device.

Hope this helps, good luck,

Alan

Finally, an excuse to get one of these....

C'mon Wes, you're a Ham!
Scavenge the parts from an old cellphone or dead radio.?
I use a hot air gun to loosen the parts.?
73... Larry



On Wed, 16 Oct 2019 at 5:01 PM, N9KDY<n9kdy@...> wrote: > Just small correction - pulldown 5k1 resistors on NanoVNA

Haven't opened the case yet.? Please, which form factor SM 5.1k
resistors?? Wish I had known this before I put that order in for SMA
connectors at Digi-Key....? I hate paying ten bucks shipping for fifty
cents-worth of parts.

--
Wes Will
N9KDY

What I want is a slightly larger display, a 3.2" or a 3.5" is not that much more expensive...
But I also know: the most dangerous thing in the world beside a programmer with an soldering iron is a user with an idea...

I'm observing that the Text window (left side of the display) resizes horizontally when marker data updates. This causes the displayed charts to resize as needed to fit the screen, and it creates a rather annoying video jitter in continuous sweep mode.

If I turn off all markers it appears mostly stable, and also if I stop the continuous sweep.

With markers off and a Smith chart displayed a similar condition reappears, but this time it seems to resize everything vertically, and a horizontal scroll bar appears and disappears at the bottom of the display.

I'm running this on a Windows 10 desktop, with edy555's version 0.2.3 firmware loaded on my NanoVNA. My display is set to the Windows 10 installation default of 1920 x 1080 (Recommended).

Changes to screen resolution or whether displayed full screen or as a window doesn't seem to alter this behavior.

Is anybody else seeing this behavior?

--
73

Gary, N3GO

Jacon Zar wrote:

socket pitch distance seems to be 0.5mm,
so resistors should be as small as possible. T

I was kind of hoping for something like "0603" or "0402" - standard name for the sizes of passive components. I'll just open it up and have a look, thanks anyway.

--
Wes Will
N9KDY

Thanks, Oristo. That fixed it. The key thing that finally made it work was when I Uninstalled the old driver before starting up Driver Wizard. Otherwise it just kept telling me I already had the best driver for my device.

Signal levels may be a problem. Where it is best to put an attenuator.

#51: the full final report 1 with contiguous full online images is here:



51#

Indeed ...Just thought I'd inject (from nanoVNA) CH0 into base (via bias-t and attenuator) monitorCH1 out on collector (via bias-t) and look at screen ...close enough for me

Jim

#50 : The Full Final Report 1 :
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Nominal Values Zinp = ( Rinp , Xinp )
of our Standard [ref2007box], in terms of
frequency, using [NanoVNA] and [VNA]
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
[NanoVNA] ~ [VNA] Comparison

#30 : our final report 1 - 6 October 2019 :
/g/nanovna-users/message/4179

- also @Gary O'Neil - 8 October 2019 -
/g/nanovna-users/message/4385


Hello,

Allow us, please, to present the steps by which we got the
results of our final report 1.

- - - - - - (c) gin&pez@arg (cc-by-4.0) 2019 : start - - - - - -

First of all, in order to set up a Somehow Reliable Comparison
between our [NanoVNA] and our [VNA], we decided to put aside
the sma/M SLO "Standards" and use our TypeN/M 50 Ohm SLO
'Standards', as well as our Standard [ref2007box], to both our
[NanoVNA] and [VNA]. So, to get the Same Reference Plane
for both instruments, we used our [sma/M-to-typeN/F 50 Ohm]
adapter directly connected to [CH0] port of [NanoVNA].

After that, since we already had our [VNA] results under these
very same SLO+[ref2007box] conditions, we used only Putty to
collect the measurements from [NanoVNA] and proceed step-by-step
to the following graphics:

I/III
The four 4 measurements : ( s, l, o, gamma ) needed
for our expression of Gamma:

#42 : The compact SLO formula for [AnyVNA]:
/g/nanovna-users/message/4747
12 October 2019

by using our [NanoVNA] : RED points in the following Figures,
as well as by our [VNA] : BLUE points in the same Figures :

I.1/4 : SHORT CIRCUIT Measurements : s
Magnitude :
Argument :

I.2/4 : (MATCHING) LOAD Measurements : l
Magnitude :
Argument :

I.3/4 : OPEN CIRCUIT Measurements : o
Magnitude:
Argument :

I.4/4 : Our Standard [ref2007box] : gamma
Magnitude:
Argument :

II/III
The Nominal Value Gamma of Our Standard [ref2007box]:

By substitution of the above measurements - from I.1/4 to I.4/4 -
to our expression:



we got for the Nominal Value Gamma of Our Standard [ref2007box],
in terms of frequency, once more:

RED points in the following Figures by using our [NanoVNA],
BLUE points in the same Figures, by using our [VNA]:

Magnitude :
Argument :

III
The Nominal Values of Zinp for Our Standard [ref2007box]:

By using the well-known formula :

Zinp = Zo*(1+Gamma)/(1-Gamma)

where Zinp and Gamma are, in general, Complex variables
and Zo is the Real Nominal Value = 50 Ohm

we got the two Parts of Zinp, as follows:

Real Part :
Imaginary Part :

#30 : our final report 1 - 6 October 2019 :
/g/nanovna-users/message/4179

- - - end : (c) gin&pez@arg (cc-by-4.0) 2019 - - - - - - - - - -

Sincerely,

gin&pez@arg

50#