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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? To be submitted to the group for critique and correction? I would add them to the archive of documentation, for the possible edification of other new people, of course.

Step one, step two, et c., sort of really simple things, starting with basic calibration.

Maybe, "Find the resonant frequency of this antenna-feedline-filter-(whatever)" could be next? Those sorts of things a ham operator might want to know how to do today, rather than spending weeks learning esoterica. (Not a thing wrong with esoterica, just not precisely useful on a day-to-day basis when all you might really need at the moment is where to cut the dipole.)

What else in this vein comes to mind? Does this already exist somewhere? Or is this the wrong forum for such? I'm new here, and don't wish to presume. (I've got decades of practice at being wrong, I'm used to it, and have become unfortunately quite good at it.)


--
Wes Will
N9KDY

Wes,
You will find most of the info you're looking for in the forum's WIKI and FILES areas.There are app notes, 'just starting' notes and most other references there.After you browse those areas and have read up on the latest version of the User Guide from Oct 2, you should have a better understanding.
When browsing the forum, set the mode to TOPICS instead of individual messages - you can scroll through faster.
Also, browse the photos section. If you see something intersting, look at the date it was uploaded and go to the messages for that period in time to find more info.
But by all means - play with it!! (after you've calibrated it and don't forget to press RESET, then CALIBRATE to start - it's all in the WIKI)
Cheers,Larry

Maybe, "Find the resonant frequency of this
antenna-feedline-filter-(whatever)" could be next?

If you check out Wiki Application Notes, then
you will discover some are simply links to useful messages.

If "Application Notes" seems too stuffy or ambitious, we could start a Wiki "How-To" page.

Keep in mind key word search
from /g/nanovna-users/wiki
and /g/nanovna-users/messages

FWIW, "resonant frequency" gets no hits in Wiki, but 17 in Messages;
sorting and supplementing those might yield a useful HowTo or three...

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:

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

Citing in messages helpful specific URLs applicable to nanoVNA (and
why) has value.

Well, it's actually an itty-bitty 2-port VNA that, within its specs, provides both reflected and through measurements of RF circuits. So, for they typical ham, mostly antennas, and maybe filters. Considering that most 1-port antenna analyzers are ~$300-900, it's pretty amazing. I found that several evenings reading of VNA basics from the Agilent and Aristu documents to be helpful. After all that, tossing away advanced microwave engineering techniques leaves a decent understanding of using a VNA (along with simulation software like mmana and simsmith) in designing and tuning antennas that are {somewhat longer} than 4cm... ;-)
But seriously... For practical applications, set up the screen to to show SWR, resistance, and reactance, and get out your microscope so you can read the screen, and it will become apparent that dipole length controls reactance (+-jX), and height above ground (for a big horizontal dipole) controls resistance...
Then, since it measures phase, there's the whole issue of "where is the reference plane?" and how to calibrate it at the desired plane. Like, you could calibrate it at the end of a 100 feet of coax, then connect that to an antenna, hoist it 60 feet in the air, and measure the actual feed-point impedance, in its environment, from a convenient distance.
Unfortunately, it isn't likely there will be any detailed written procedures for performing specific tasks, as a VNA is a tool that is adapted to the task at hand. But with only consideration of SWR and R+jX, it's much more useful than a simple SWR meter (or basic antenna analyzer), and it will do much beyond that, if you study into the engineering side of VNA measurement a bit. Collect and read the various PDF documents in the files section, and the many posts about calibrating to a reference plane, and it'll all come together. Then you can set it up to do whatever you want.
As a former industrial instrument technician (having calibrated thousands of things), followed by 4 years of writing procedures, I can tell you it isn't easy! as procedures need to be general enough to cover variables in use-cases, but specific enough to be useful. Indeed, as publisher of a rather large how-to web site, I still find users' sending questions of details not adequately covered, even on long and detailed articles I wrote 20 years ago.
73, --kv5r

An excellent idea.

Someone new to VNA's and what a complex impedance is will be overwhelmed
if told to check the wiki, all the forum posts, and read some Agilent document.
They just want to measure their antenna's SWR (they think).
Or maybe sweep a filter.
A first document should tell them that without having to first wade through a lot of new material.

We need a single document that tells how to charge it, turn it on, configure it to show SWR
and complex impedance, and then sweep across a range of frequencies.
How to measure that filter.
How to deal with the user interface, what parts of the menu structure they can ignore,

If ambitious, further sections of this document could give a primer on what a complex impedance is.
When calibration might be a good idea.
What a reference plane is.


Maybe set up a few example exercises, using a 100 pF cap and a 100 ohm resistor so the parts are likely on hand.
Keep the frequency fairly low so it's easy to reproduce.
Show them how to measure these parts in various configurations, and what results to expect.
Perhaps add a hand wound inductor to the mix.
And what happens when this stuff is put on the end of 25 feet of cheap RG79 coax.

An appendix with links into other documents with a brief description of what can be found there.
Things like transmission line theory, impedance matching, Smith charts, S parameters.

Jerry, KE7ER

I agree....... my NANOvna and my Antuino sit there unused because my old brain and the fact that my medical education didn’t cover electrical or RF engineering I am hopelessly lost in using these neat and “simple” devices and life doesn’t have enough days left to live in books learning from scratch all the stuff that has been in this group since the vna came out. I should be happy as my YOuKits FG-01 does just what I need to set up an antenna but these new toys piqued my interest. I want to be part of the “in” group but find it is getting more difficult.

Dave K8WPE since 1960

David J. Wilcox K8WPE’s iPad

Someone new to VNA's and what a complex impedance is will be overwhelmed
if told to check the wiki, all the forum posts, and read some Agilent
document.

Introductions are tough; new owners may be impatient as well as uninformed and/or misinformed.
NanoVNAs are not all the same; some have battery, calibration kit and already touch screen and SOLT calibration.
* How many new users want to go thru exhaustive instructions for all?
Some menus and functions change among firmware versions
* Should new user instructions first try to install some latest stable firmware?

They just want to measure their antenna's SWR (they think).
Or maybe sweep a filter.
A first document should tell them that without having to first wade through a
lot of new material.

We need a single document that tells how to charge it, turn it on, configure
it to show SWR
and complex impedance, and then sweep across a range of frequencies.
How to measure that filter.
How to deal with the user interface, what parts of the menu structure they can
ignore,

If ambitious, further sections of this document could give a primer on what a
complex impedance is.
When calibration might be a good idea.

Without ensuring calibration for whatever configuration was used for the above,
SWR measurements and/or filter sweeps are probably doomed.

What a reference plane is.

Maybe set up a few example exercises, using a 100 pF cap and a 100 ohm
resistor so the parts are likely on hand.
Keep the frequency fairly low so it's easy to reproduce.
Show them how to measure these parts in various configurations, and what
results to expect.
Perhaps add a hand wound inductor to the mix.
And what happens when this stuff is put on the end of 25 feet of cheap RG79
coax.

An appendix with links into other documents with a brief description of what
can be found there.
Things like transmission line theory, impedance matching, Smith charts, S
parameters.

Several have worked on pieces of the above; seamless integration could be daunting.

I see value in an online "Start Here" with e.g. animated GIFs for touch screen navigation
and to that end ordered an iPhone tripod adapter

On Thu, 17 Oct 2019 at 18:09, KV5R <kv5r@...> wrote:

As a former industrial instrument technician (having calibrated thousands of things), followed by 4 years of writing procedures, I can tell you it isn't easy! as procedures need to be general enough to cover variables in use-cases, but specific enough to be useful. Indeed, as publisher of a rather large how-to web site, I still find users' sending questions of details not adequately covered, even on long and detailed articles I wrote 20 years ago.

In theory, a wiki is a very good answer to the very real problems of
having one person write and maintain all of the comprehensive
documentation for an open source project. The community can do a more
efficient job than a single person. For example, I might be interested
in the TDR aspects, so I might work on the TDR pages in the wiki.
Someone else is interested in the Smith Chart, and she works on those
pages. Someone else is interested in hardware mods, and he works on
those pages. You get the idea.

This is theoretical, because it seems very difficult to convince
community members (in any open source project) to maintain the wiki
pages they find interesting/in need of work.
--buck

Wiki search box for TDR / Smith / mods:

For example, I might be interested in the TDR aspects, so I might work on the TDR pages in the wiki.

Someone else is interested in the Smith Chart, and she works on those pages.

/g/nanovna-users/wiki/External-links

Someone else is interested in hardware mods, and he works on those pages.

/g/nanovna-users/wiki/Mods-and-Design-Notes

On Thu, 17 Oct 2019 at 05:39, YT9TP - Pedja via Groups.Io <yt9tp=
[email protected]> wrote:

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

Unfortunately, almost all the YouTube videos on VNAs have serious mistakes.

One was discussed on here a week or so ago. Another by the same author is
flawed too, which I have discussed with him privately. There are numerous
videos on making VNA calibration kits which are flawed. There’s a video on
how to do a 2-port calibration of an HP 8753 VNA which is flawed.

I am personally of the opinion that YouTube is full of people making videos
about subjects they have little knowledge of. The unfortunate thing is that
these people get lots of thumbs up, and lots of followers.

This is one of my favourites for an idiot that has 50500 followers, get 97%
thumbs up for his video, yet is fundamentally flawed in numerous ways.



We have this idiot with 229,000 subscribers measuring the noise on the 6.5
digit multimeter by looking at how much the digits change when connected to
a laboratory power supply.



He does not appreciate that a power supply would have far more noise than a
6.5 digit multimeter.

So in summary, I would advise against recommending newcomers look to
YouTube for information.

I would also point out that most hams don’t understand complex mathematics.
Most don’t know what resonance is.

I would consider a basic introduction should consider VSWR and transmission
and reflection from filters.

Dave.


--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom

On 19.10.2019 15:21, Dr. David Kirkby from Kirkby Microwave Ltd wrote:

So in summary, I would advise against recommending newcomers look to
YouTube for information.

But, if someone who knows make selection and list tutorials that are good that would make a difference, right?


--
73,
Pedja YT9TP

Checkout:

I am all in favor of a "VNA For Dummies" book !!

73, Dick, W1KSZ

ps: still trying to figure out a Smith Chart

Sent from Outlook<>
________________________________
From: [email protected] <[email protected]> on behalf of YT9TP - Pedja via Groups.Io <yt9tp@...>
Sent: Saturday, October 19, 2019 6:44 AM
To: [email protected] <[email protected]>
Subject: Re: [nanovna-users] Abbreviated documentation for more simplistic tasks?



On 19.10.2019 15:21, Dr. David Kirkby from Kirkby Microwave Ltd wrote:

So in summary, I would advise against recommending newcomers look to
YouTube for information.

But, if someone who knows make selection and list tutorials that are
good that would make a difference, right?


--
73,
Pedja YT9TP

Checkout:

Oristo,

You make some good points.

Perhaps the tutorial assumes the user buys a particular nanoVNA, such as from Hugen.


A better solution would be to cover the the more popular variants with section headings
that clearly state whether or not the reader will care about that particular section.
For example:

Did your unit not arrive with a battery included, a rectangular silver lump
between the main PC board and the back panel?
Then you either must always have power applied through the USB connector
when using it, or you will have to obtain and install a battery.
Here are potential sources for a battery, and how to install it .....

When you first turn it on, if the screen looks like this photo:
<photo>
Then instructions for navigating the menus are as follows ....


The basic instructions should point to a good document on how to
download different firmware. But I'd assume that any firmware will be
sufficient for basic use, such as finding the SWR of an antenna or the
response of a filter. Or determining the complex impedance of a load.

A good beginner's document will indeed be tough to get right, for lots of reasons.
I'd think it will have to be an integrated whole written by one author,
Supplementary material could be pointers into the wiki,
though I'm a bit worried about random people going in and "fixing" wiki pages.
Perhaps once the wiki has developed some, we have a group of
knowledgeable people evaluate/edit the key material into a User's Guide.

Jerry, KE7ER

From: Dick

I am all in favor of a "VNA For Dummies" book !!

73, Dick, W1KSZ

ps: still trying to figure out a Smith Chart
========================================================

Dick,

Such a book was published for the DGS8SAQ VNWA 2/3 Vector Network Analyser.



While it's for different hardware, the basic principles should be the same. You might look out for videos by DGS8SAQ as well.

73,
David GM8ARV
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

On Sat, Oct 19, 2019 at 06:48 AM, Dick wrote:

ps: still trying to figure out a Smith Chart

Dick, some years ago I wrote up some notes on the Smith Chart (basically describing where those funny curves come from). It might not be what you are looking for, but if interested, go here:



- Jeff, k6jca

I see value in an online "Start Here" with e.g. animated GIFs for touch screen navigation

Such animated GIFs are too large to load and run quickly, so mp4..

Is something like this useful?

some years ago I wrote up some notes on the Smith Chart

Added to Wiki
/g/nanovna-users/wiki/External-links

Supplementary material could be pointers into the wiki,
though I'm a bit worried about random people going in and "fixing" wiki pages.

Wiki has a tool for differencing revisions;
don't know what happens if/when more than one simultaneous edit..

I don't recall any issue reported resolved by checking the Wiki,
wonder whether it gets much use at all.