Hello guys,
I'm new here and I'm having a hard time figuring out how to use my NanoVNA to measure those things.
I made a search in the group topics but it's always about the results and I can't really find any simple tutorial on how to take those measurements.
- About transformers I would like to measure the ratio but I don't really know where to plug my nanovna to do that and how to configure it.
I have "three outputs" primary, common and secondary. Should I use the 2 ports of the nanoVna to try and obtain a result ?
- for the inductors I would like to know if I can just plug to the 2 ends of it and find it's value ? which value should I show on my display ?
- for the trap filter I used the method where you just go through the inductor with a cable and look at the phase but I'm not really sure it's the best way to do it, can I just plus to A and B on my graph and look at the result instead ?

If you have any link or video that shows the detail of the measurement and wiring process I'd greatly appreciate that.
As I said I'm a new ham so I don't really know how to use my VNA except for measuring SWR of my antenna but I'm convince it's a great tool, I just need to learn how to use it.

The attachment should at least get you going.

Dave - WØLEV


On Thu, Nov 7, 2024 at 12:08 PM Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

Hello guys,
I'm new here and I'm having a hard time figuring out how to use my NanoVNA
to measure those things.
I made a search in the group topics but it's always about the results and
I can't really find any simple tutorial on how to take those measurements.
- About transformers I would like to measure the ratio but I don't really
know where to plug my nanovna to do that and how to configure it.
I have "three outputs" primary, common and secondary. Should I use the 2
ports of the nanoVna to try and obtain a result ?
- for the inductors I would like to know if I can just plug to the 2 ends
of it and find it's value ? which value should I show on my display ?
- for the trap filter I used the method where you just go through the
inductor with a cable and look at the phase but I'm not really sure it's
the best way to do it, can I just plus to A and B on my graph and look at
the result instead ?

If you have any link or video that shows the detail of the measurement and
wiring process I'd greatly appreciate that.
As I said I'm a new ham so I don't really know how to use my VNA except
for measuring SWR of my antenna but I'm convince it's a great tool, I just
need to learn how to use it.

--

*Dave - WØLEV*


--
Dave - WØLEV

On 11/7/2024 12:26 PM, W0LEV wrote:

The attachment should at least get you going.

Dave - WØLEV


On Thu, Nov 7, 2024 at 12:08 PM Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

<snip>

Thanks Dave, looks good.

Mike C. Sand Mtn GA

Really interesting document, I'll definitely try to reproduce the steps and I will be really happy if I can make it work.
And also really nice little fixture.
I did a bit of digging and found this kind of board, I guess it would be easier for me to calibrate as I don't have any non inductive precision resistance to calibrate.
Did any of you ever used that before ?

Gervail:

Thanks for the tip*. There really is NO definitive, easy-to-understand
users' manual for the NanoVNA-H4. There are many YouTube sites that you can
find. I've looked at many of them as I learned how to use mine.
One guy's presentations have impressed me the most. His call is W2AEW, and
the YouTube to one of his instructions is at:
https://youtu.be/xa6dqx9udcg?feature=shared.

* Caution about that clever "breadboard" that you showed: I think it will
be a great one, EXCEPT at higher frequencies in VHF/UHF. That's just
because the lead-lengths become important up there. But, I'm gonna have to
try it out for myself. [I just bought a pair of shielded test leads that
have male SMA at one end and small alligator clips at the other. The trick
in selecting was to find a pair where the shielding went as far as possible
to the end. Many of the ones i found on AMAZON had a short jumper from the
SMA connector to a splice point, from which two separate long lengths of
unshielded wire emerged to go to the alligator clips. I think that
arrangement is a big mistake. I have some hf bandpass filters to align;
will see how these new cables do --once they get shipped in a couple of
weeks [Hurry up, Guangzhou--I havent got all day!]

73
Bill K2TNO



On Thu, Nov 7, 2024 at 8:50 PM Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

Really interesting document, I'll definitely try to reproduce the steps
and I will be really happy if I can make it work.
And also really nice little fixture.
I did a bit of digging and found this kind of board, I guess it would be
easier for me to calibrate as I don't have any non inductive precision
resistance to calibrate.
Did any of you ever used that before ?

You don't need "precision" resistors. "Close enough" like 47 or 51-ohms
for a 50-ohm non-inductive resistor. The most importance consideration is
that it's non-inductive.

Dave - WØLEV

On Thu, Nov 7, 2024 at 9:08 PM William Schrader via groups.io <wtschrader=
gmail.com@groups.io> wrote:

Gervail:

Thanks for the tip*. There really is NO definitive, easy-to-understand
users' manual for the NanoVNA-H4. There are many YouTube sites that you can
find. I've looked at many of them as I learned how to use mine.
One guy's presentations have impressed me the most. His call is W2AEW, and
the YouTube to one of his instructions is at:
https://youtu.be/xa6dqx9udcg?feature=shared.

* Caution about that clever "breadboard" that you showed: I think it will
be a great one, EXCEPT at higher frequencies in VHF/UHF. That's just
because the lead-lengths become important up there. But, I'm gonna have to
try it out for myself. [I just bought a pair of shielded test leads that
have male SMA at one end and small alligator clips at the other. The trick
in selecting was to find a pair where the shielding went as far as possible
to the end. Many of the ones i found on AMAZON had a short jumper from the
SMA connector to a splice point, from which two separate long lengths of
unshielded wire emerged to go to the alligator clips. I think that
arrangement is a big mistake. I have some hf bandpass filters to align;
will see how these new cables do --once they get shipped in a couple of
weeks [Hurry up, Guangzhou--I havent got all day!]

73
Bill K2TNO



On Thu, Nov 7, 2024 at 8:50 PM Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

Really interesting document, I'll definitely try to reproduce the steps
and I will be really happy if I can make it work.
And also really nice little fixture.
I did a bit of digging and found this kind of board, I guess it would be
easier for me to calibrate as I don't have any non inductive precision
resistance to calibrate.
Did any of you ever used that before ?

--

*Dave - WØLEV*


--
Dave - WØLEV

Those are good up to ~100MHz, really useful
for all sorts of small components. Don't overpay for it,
these usually go for ~$3: https://s.click.aliexpress.com/e/_DB7YAkD

A really useful addition when using this board are these pins (the
ones with pins on both sides):
https://s.click.aliexpress.com/e/_DDPbVQD (bit pricey for what they are).
You can use them to make your own calibration standards, just solder
2 SMD 100Ω resistors in parallel to the pins.
Also great with the female variety when measuring single SMD components.
Solder the female pins to an SMA connector, use your standards to
calibrate and then use
the male pins to hold your DUT.




On Thu, 7 Nov 2024 at 21:50, Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

Really interesting document, I'll definitely try to reproduce the steps and I will be really happy if I can make it work.
And also really nice little fixture.
I did a bit of digging and found this kind of board, I guess it would be easier for me to calibrate as I don't have any non inductive precision resistance to calibrate.
Did any of you ever used that before ?

Good to know about the limitations in the VHF UHF domain. I'll keep that in mind when testing for now I'll mostly stay in the HF domain trying to analyse my "future" EFHW antenna.
I guess as you said William I'll need to play with it and watch a lot of youtube videos to increase my understanding of what's going on and how to measure it.
I prefer testing and understanding what's going on rather than just building something as someone said and just assume it works so I'll probably come back with more questions :)

Dave I'll need to get my hand on some non-inductive resistor then !

Excatly when I just ordered Draganm thanks for the tip about the other "pins".
Do you have any aliexpress link where I can find the SMD resistors ? is the non-inductive part really important under 100Mhw though ?

Sorry, Dragan.. querty keyboard..

Yes non-inductive is very important.

https://www.aliexpress.com/w/wholesale-smd-resistor-book.html?spm=a2g0o.best.search.0

One of these will suffice

Any 0805 resistor will do, they are all "non inductive".
Just search for SMD resistors. You usually get a couple
with that board kit.

On Thu, 7 Nov 2024 at 22:51, Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

Excatly when I just ordered Draganm thanks for the tip about the other "pins".
Do you have any aliexpress link where I can find the SMD resistors ? is the non-inductive part really important under 100Mhw though ?

Here is another fixture idea. The connectors are Pomona BNC female #2451 and the contacts are a Phoenix Contact #1190363. In the photos the "short" is installed. You can see that there is an easy match between the BNC center conductor and the pin of the Phoenix contact. Three #4 standoffs 9/16" are used and it is epoxied after assembly and soldering.

https://groups.io/g/nanovna-users/album?id=298861

Mouser link to Phoenix Contact: https://www.mouser.com/ProductDetail/Phoenix-Contact/1190363?qs=QNEnbhJQKvZM1o20TNh%252B9Q%3D%3D

Mouser link to Pomona BNC: https://www.mouser.com/ProductDetail/Pomona-Electronics/2451?qs=sGAEpiMZZMvlX3nhDDO4ALdU0XBssY1MHxgcBUfKO74%3D

I should note that the idea for this came from Kurt Poulsen in the VNWA group.

Gervais:
I have good news--- I've had similar difficulties getting to understand
what to do with my NanoVNA-H4.

I came upon a very informative book that I bought on Amazon to read on my
Kindle app in this laptop.

It's called "NanoVNAs Explained for the Radio Amateur: The author is Mike
Richards, G4WNC. It's copyright 2022, and the price is about USD 20, as I
recall.

The great thing is that he starts out explaining what VNA's are, how & when
invented. And then he moves on to the NanoVNA, explaining what the two
ports are, and why they are called "S11" or "S21"---- etc.

Then he moves on to examples and limitations of these inexpensive units
[mostly bandwidth and sensitivity at VHF and above.]

Finally, he tells about a freeware program called "NanoVNA-saver"---where
to download it, and what it lets you do. The examples in that section are
worth the price of the book!

The entire Part 2 of the book is a series of sections on topics like
"antenna feeder loss", "Passive filter measurement" and "Cable checker" to
name a few.

Oh! He also has a very clear explanation of how a Smith Chart works.

73
Bill, K2TNO

On Thu, Nov 7, 2024 at 7:08 AM Gervail Antoine via groups.io
<gervail.antoine@...> wrote:

Hello guys,
I'm new here and I'm having a hard time figuring out how to use my NanoVNA
to measure those things.
I made a search in the group topics but it's always about the results and
I can't really find any simple tutorial on how to take those measurements.
- About transformers I would like to measure the ratio but I don't really
know where to plug my nanovna to do that and how to configure it.
I have "three outputs" primary, common and secondary. Should I use the 2
ports of the nanoVna to try and obtain a result ?
- for the inductors I would like to know if I can just plug to the 2 ends
of it and find it's value ? which value should I show on my display ?
- for the trap filter I used the method where you just go through the
inductor with a cable and look at the phase but I'm not really sure it's
the best way to do it, can I just plus to A and B on my graph and look at
the result instead ?

If you have any link or video that shows the detail of the measurement and
wiring process I'd greatly appreciate that.
As I said I'm a new ham so I don't really know how to use my VNA except
for measuring SWR of my antenna but I'm convince it's a great tool, I just
need to learn how to use it.

Mike M really interesting fixture it looks really good. I'll probably try to make it with our european version of the electric connector (wago, it looks the same).
William I took a look at the book you recommended and bought it, I have finished the part about the smith chart and it's indeed really good.
I definitely prefer text (or book) explanation than video so it's really cool, thanks for the advice !

On Fri, Nov 8, 2024 at 06:24 PM, William Schrader wrote:

It's called "NanoVNAs Explained for the Radio Amateur:

So I bought the book following your advice and it's actually really good, I understood a lot more about the nanoVNA reading it.
Sadly the only part that was really interesting for me was not really clear.
Since then I received my test board so I just tried to do some measurements a bit randomly.
Here's what I did (once calibrated) I connected my trap to the center of S21 and S11 and I got what's on image A.
I'm I correct assuming that |Z| represent the width of frequency that are filtered by my trap and that the change in phase represent the frequency where my trap is tuned ?
For image B I did almost the same measurements but only using S11. ( so one channel) |Z| looks the same (is it the other way to measure it ?) but Q (is it Q factor of my filter) is not the same at all.
I don't really know if I'm doing everything wrong or if I'm on the good track ?
And I also used the method were I pass a wire through the toroid and the frequency was not that far from what I measured with the methods above.
(sorry for the bad picture I still didn't figured how to install nanovna saver...)

use nanovna_app instead :-)

dg9bfc sigi

Am 22.11.2024 um 16:49 schrieb Antoine (F4LVL) via groups.io:

does nanovna_app support linux ?

I use it under Wine and that works good.