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I bought a NANO VNA when they first came out to use as a antenna analyzer. I sold it after I bought a regular analyzer and since bought another VNA
This is new updated software is confusing compared to the fist one I had ?
Trying to read the manual im getting more confused trying to figure out the basics of swr measurement. Can anyone give me a dumbed down step by step version how to set the new software for SWR?
It would be much appreciated ?

There is an Absolute Beginners Guide to the NanoVNA in the Files section of this group

/g/nanovna-users/files/Absolute%20Beginner%20Guide%20to%20The%20NanoVNA/Absolute_Beginner_Guide_NanoVNA_v1_6.pdf

Roger

Mike,

I found these short videos very helpful for doing SWR readings on antennas.

How to read SWR on nanoVNA.


How to calibrate nanoVNA.

Thanks for trying to be a help brother. I watched both those videos before but something in them just didn't click.
I just sat down and read the beginner's guide start to finish and setting this one up is no different the the old one i had! Lol
I think trying to read the (official) factory guide get me all twisted up trying to follow it. Smh I bet tomorrow I have my antenna up and running finally ?

A NanoVNA calculates the SWR for you. If this SWR is so important for an OM at the output of its Tx, it is not a very relevant measurement produced by a NanoVNA.

SWR is a number and only *one*

A NanoVNA is a measuring device that allows you to measure a couple of *two* numbers as a function of frequency using only port 0. The NanaoVNA will present these two numbers to you in multiple forms adapted to a particular use. The two most important:
- The impedance in the form A+jB (A et B in ?)
- Parameter S11 in the form again a+jb

For example, if you notice that at the output of your Tx you have a high SWR, not very compatible with a Tx with transistors, what is relevant is to correct your installation to reduce this SWR. This SWR is the consequence of the fact that the impedance brought back by your antenna + the transmission line is not 50 + j0 or 50. You must correct your installation and the NanoVNA will help you calculate the device to be implemented.

A simple doublet resonating at the frequency of use never presents an impedance of 50. Do not stop at the evaluation of the SWR by your NanoVNA. The SWR is only a sterile observation.
--
F1AMM
Fran?ois

I mainly just want to use it to find the best position on my coil! Lol
Its small a lot more portable then a mfj and affordable if it breaks in the field.
The stock owner manual goes way overboard with things for what I want lol

I mainly just want to use it to find the best position on my coil! Lol

Hello
Some OMs, in fact, temporarily replace their Tx with a nanoVNA to adjust their tuning box. You have to be careful that the TX does not end up in front of the NanoVNA.

In France we call that: giving jam to the pigs ("donner de la confiture aux cochons") :)
--
F1AMM
Fran?ois

De la part de Mike Anderson/KF?AWL
Envoyé : samedi 10 juin 2023 06:50

Hi Fran?ois,

As an example, I routinely use a nanoVNA or antenna analyser to adjust my 136 and 475 kHz antennas at my home and remote QTH's, via a switch or PC-selected port which routes the antenna path to either the Class D/E amplifier or the analyser. To avoid the sort of trouble you correctly point out, activating the switch simultaneously disables the amplifier drive.

For my remote station, VK6MJM, I use a RigExpert AA-30.Zero "naked"analyser under station PC control, largely because I've not found any nanoVNA application reliable enough to connect faultlessly over long periods. The RigExpert Antscope software, although relatively basic, performs better in this regard. (The station is 300 km away).

I like your proverb: there's a near equivalent in English which talks about "casting pearls before swine" .

73, Peter.

Ok new question.
I'm following the setup in the beginner's guide for process of calibration, get it done according to the guide and try to verify with the Smith chart . I screw my open to port 1 trace 1 (trace 0 is my swr trace) were I did the calibrate and according to the guide it should go to the far right of the Smith chart. It dont, it just sits in the same place. What am I doing wrong here?
I'm following it step by step!

On Sun, Jun 11, 2023 at 09:16 AM, Mike Anderson/KF?AWL wrote:

Ok new question.
I'm following the setup in the beginner's guide for process of calibration,
get it done according to the guide and try to verify with the Smith chart . I
screw my open to port 1 trace 1 (trace 0 is my swr trace) were I did the
calibrate and according to the guide it should go to the far right of the
Smith chart. It dont, it just sits in the same place. What am I doing wrong
here?
I'm following it step by step!

Use the Smith Chart display and make sure that the trace is set to S11

Roger

Use the Smith Chart display and make sure that the trace is set to S11

And you (very confusingly) need to connect to and calibrate port 0 for S11 measurements. Port 1 (normally 2) is the return port for S21 measurements.

I think that the original nanoVNA designer did a disservice when they labeled the RF ports 0 and 1 (computer style) when everyone else in the known universe's VNA (and the S-parameter numbering and equations) use ports 1 and 2; S11, S21 is a lot more meaningful that way.
Similarly, everyone else uses trace 1,2,3... and save/recall register 1,2,3...
This kind of avoidable confusion has got to be tough on beginners.
Best regards, Don Brant

Ok got the Smith chart working in conjunction with SWR reading on port one and verified my calibration (honestly it was a fluke and not sure how I did it lol)
So got that issue solved this new software in this one has more settings and things in the menu that weren't there before and are not meantioned in the beginner's guide now.
So on we go!
Thanks for the help guys ill be confused again I'm sure lol

Far right is very high resistance, far left is very low resistance. Your open calibration looks good!

Sorry, didn't read your post correctly. Make sure you save the calibration, Then look on the left of the display to make sure you recall the saved calibration.

Ok now, is there a easy way to figure out the resonance of the antenna?
I'm useing a different whip and ground plane so the factory (height) on the coil is going to be off so I'm wondering if there is a easy way to get a idea of where the coil is setting the antenna up at.

On Sun, Jun 11, 2023 at 12:28 PM, Mike Anderson/KF?AWL wrote:

Ok now, is there a easy way to figure out the resonance of the antenna?
I'm useing a different whip and ground plane so the factory (height) on the
coil is going to be off so I'm wondering if there is a easy way to get a idea
of where the coil is setting the antenna up at.

Mike,

W2AEW has an excellent series of videos on how to use the NanoVNA to measure and adjust antennas. I think you will find this one worth watching.



Roger

Thanks Roger and everyone else that is helping me learn on this journey. Eventually I'll get it all locked down and be able to pay it forward I hope ?

Ok Roger, ? I watched the video but didn't glean a lot of learning from it. I'm not understanding were he is reading his freq from ? ?
At the moment I'm trying to set the coil in the center of the 10m band so I have a reference point of were I need to start for the rest of the bands but I'm not understanding something ?
In very simple terms, is there a way to set the vna look at what freq the antenna is matched at (ok its off so I need to make the coil shorter or longer to get to my freq) move the coil check the reading (ok that was the wrong direction, move THE PICKUP a few clicks the other way on the coil)
This is frustrating me because I'm sure its a simple process but I'm totally flubbing it up ?

Mike,

Just set the start and stop frequencies to the widest approximate frequency range where you expect the antenna will be tuned to. For 10M try 25 to 32 MHz. The calibrate for this range. Set the yellow trace to read SWR and you should see a frequency where the SWR is at a minimum. Then use the rocker switch to move the marker to this point and you can read the frequency and SWR. Then slowly adjust your coil and you should see the SWR minimum move. You can "zoom in" by setting the start a bit higher and the stop a bit lower and the NanoVNA will interpolate the calibration.

Roger

Ok sorry to be such a pain.
I really want to get this up and rolling for field day and some demonstrations coming up and I feel like a idiot for not catching on.
Thanks for being so patient with me.