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Date
Delivery

 

I ordered the updated, 3 button "F" model on February 29, 2020. I was delivered yesterday, May 26th, by the USPS. Tracking consistently showed that the parcel had been shipped some time in early March but that it was stuck in either outgoing customs or incoming customs in the U.S. The little training kit that I ordered at the same time was delivered in a timely manner and I have had it for almost 3 months now.

Hang in there, things will work out!

KM5XK
Re: Measure Crystal Characteristics Automatically Using a NanoVNA #xtals

 

Thanks, Herb! Crystals are one of my interests.

I tried running it with Python2.x and 3.x, it apparently requires Python3.7. Haven't tried actually measuring a crystal with it yet, but this works, anyway:



jim@jim-P55A-UD3P:~/crystalweb$ python3.7 ./crystalweb.py --help
usage: crystalweb.py [-h] [--fixture] [--loss] [--theta THETA] [--stray STRAY]
[--repeat REPEAT] [--load LOAD] [--title TITLE]
[--device DEVICE] [--start START] [--stop STOP]
[--capture]

optional arguments:
-h, --help show this help message and exit
--fixture measure test fixture stray capacitance (default: False)
--loss measure test fixture loss (default: False)
--theta THETA phase angle for measuring bandwidth (default: 45)
--stray STRAY test fixture stray capacitance in pF, affects Co (default:
None)
--repeat REPEAT number of times to repeat measurements (default: 10)
--load LOAD test fixture source and load resistance (default: 50)
--title TITLE title of measurement (default: )
--device DEVICE name of serial port device (default: None)
--start START starting frequency of initial sweep (default: None)
--stop STOP stopping frequency of initial sweep (default: None)
--capture capture screenshots of the measurements as movie_xx.png
(default: False)
jim@jim-P55A-UD3P:~/crystalweb$
Re: NooElec 1:9 balun #test-jig

 

Hello Roger,
Thank you very much for your quick answer.
My answers are in your text:

On Wed, May 27, 2020 at 08:30 PM, Roger Need wrote:

When you replace a 50 ohm resistor load with the RG-316 cable connected to the
nanoVNA you no longer have a 50 ohm resistive load. This is due to two
factors:
- RG-316 cable is only specified as a "nominal" 50 ohm characteristic
impedance. Its characteristic impedance varies considerably with frequency as
shown below.
- The NanoVNA CH1 port is also not 50 ohms as reported by others on this site.
You can measure it yourself and see what I mean.

The net effect of these two effects is that you will see a complex impedance
at the end of the RG316 that differs from 50 ohms so the balun will not be
seeing 450 ohms and the return loss will be different.
I was my understanding, that the calibration will give at the end of the 50 cm RG-316 cable
nominal 50 Ohm impedance (reference point).

One other point. The style of 50 ohm SMA load you are using is not a good 50
ohm load. They are usually made with a 51 ohm resistor with a long lead
(inductive) and have a poor contact with the load case. So this will affect
your initial Return Loss measurement
With that 50 Ohm resistor in the picture I got a good S11 Return Loss measurement.
So, this was not my point.

The problem arised when I exchanged this 50 Ohm resistor with a 50 cm RG-315 cable,
connected to the CH1 port of the nanoVNA.
The calibration with that 50 cm RG-316 cable was made before.

So, how can I improve the situation?

73, Rudi DL5FA
Re: What apps use Touchstone files? #applications

 

Some free tools to analyze Touchstone files...



Roger
Re: What apps use Touchstone files? #applications

 

They can also be imported into a spreadsheet very easily. I have done that for making plots and doing calculations based on the data.

Roger
Re: NooElec 1:9 balun #test-jig

 

On Wed, May 27, 2020 at 11:02 AM, <reuterr@...> wrote:

I replace now the 50 Ohm resistor at the SMA plug with a coax cable RG316
to the nanoVNA CH1.
To my surprise the S11 Return loss looks much different, than with the 50 Ohm
resistor.
See: NooElelc_Balun_9-1_S21_Loss.png.

What In am doing wrong?

73, Rudi DL5FA
When you replace a 50 ohm resistor load with the RG-316 cable connected to the nanoVNA you no longer have a 50 ohm resistive load. This is due to two factors:
- RG-316 cable is only specified as a "nominal" 50 ohm characteristic impedance. Its characteristic impedance varies considerably with frequency as shown below.
- The NanoVNA CH1 port is also not 50 ohms as reported by others on this site. You can measure it yourself and see what I mean.

The net effect of these two effects is that you will see a complex impedance at the end of the RG316 that differs from 50 ohms so the balun will not be seeing 450 ohms and the return loss will be different.

One other point. The style of 50 ohm SMA load you are using is not a good 50 ohm load. They are usually made with a 51 ohm resistor with a long lead (inductive) and have a poor contact with the load case. So this will affect your initial Return Loss measurement

Roger

316.PNG
bad load.PNG

Re: What apps use Touchstone files? #applications

 

RFSim99 can also handle Touchstone device definitions.

Jose, CO2JA

On 5/27/20, Jacob Boline <mail@...> wrote:
The only programs I have used touchstone files with is Keysight ADS and
MATLAB. However, they're usually just formatted ASCII so I would be
surprised if no one else had made a parser for them.
Re: NooElec 1:9 balun #test-jig

 

I am testing the NooElec 1:9 balun V1.0.
When I measure the S11 Return Loss, see NooElec_Balun_9-1_S11_Return-Loss.png,
it behaves like the original curve balun_one_nine_return_loss_comparison_to_70mhz.png.
My measurement setup is shown in photo RF_Balun_1-9_S11_DSC08237.jpg.
The secondary side of the balun is terminated with 400R + 50 Ohm.

If I want to measure the balun *Loss* I have a problem.
See the original curve from NooElec: balun_one_nine_insertion_loss_comparison_to_70mhz.png
I replace now the 50 Ohm resistor at the SMA plug with a coax cable RG316
to the nanoVNA CH1.
To my surprise the S11 Return loss looks much different, than with the 50 Ohm resistor.
See: NooElelc_Balun_9-1_S21_Loss.png.

What In am doing wrong?

73, Rudi DL5FA

NooElec_Balun_9-1_S11_Return-Loss.png
balun_one_nine_return_loss_comparison_to_70mhz.png
RF_Balun_1-9_S11_DSC08237.jpg
balun_one_nine_insertion_loss_comparison_to_70mhz.png
NooElelc_Balun_9-1_S21_Loss.png

Re: What apps use Touchstone files? #applications

 

The only programs I have used touchstone files with is Keysight ADS and MATLAB. However, they're usually just formatted ASCII so I would be surprised if no one else had made a parser for them.
Nanovna-H4 Output Shuts off after Cal #calibration

 

Sorta new to the nanovna, used it on two antenna projects this past
weekend. When I run through the calibration process, when I click the Done
or Back menu options the output turns off. It'll stay on if I just touch
anywhere else on the screen. I'm on version 0.4.5.7. Has anyone seen this
too, maybe it's cockpit error on my end but it's easily repeatable.

73! Mark KA6WKE

Latest Video:
Website:

Re: What apps use Touchstone files? #applications

 

I worked with Touchstone some 40+ years ago. Les Besser originated this
early microwave computer modeling/analysis application of which Touchstone
was his major contribution. Of course, in its day, it ran on mainframes.
We had the IMB 370 on my job. PC's didn't exist, yet. Punched cards were
the data entry standard of the day.

Dave - Old Fossil - W?LEV

On Wed, May 27, 2020 at 8:28 AM warnergt via groups.io <warnergt=
[email protected]> wrote:

I used to use Touchstone many, many years ago. It was a great program.
I haven't worked with S parameters for a long time so I'm out of touch
with the currently available applications.
What current applications work like Touchstone and/or work with Touchstone
files?



--
*Dave - W?LEV*
*Just Let Darwin Work*
Re: What apps use Touchstone files? #applications

 

Information about Touchstone file format


Touchstone? File Format Specification Version 2.0


PS thanks, I was just looking for a specification for a given file format for export to SD Card
Re: Measure Crystal Characteristics Automatically Using a NanoVNA #xtals

 

Looks interesting, I'll need to spend a little time figuring out how to get it to run. I pulled the files and spent a few minutes with it this morning, but couldn't get it to play (yet). I'm really a noob when it comes to Python. Previous Python scripts have had installation scripts or at least a requirements doc...
Re: What apps use Touchstone files? #applications

 

Touchstone is a file format that provides a standardized way for programs to output S parameters (S11, S21) so they can be read by other programs. The extension can be .s1p, .s2p etc.

There are many programs that can import S parameters. I have a RigExpert antenna analyzer and I often import NanoVNA Touchstone files with AntScope 2 so that I can compare the measurements made with the two instruments. Antscope 2 is a free download and you can use it without a RigExpert. It has nice plotting and scaling options.

Roger
Re: What apps use Touchstone files? #applications

 

SimSmith


I used to use Touchstone many, many years ago. It was a great program.
I haven't worked with S parameters for a long time so I'm out of touch with the currently available applications.
What current applications work like Touchstone and/or work with Touchstone files?
Re: What apps use Touchstone files? #applications

 

I¡¯ve never heard of this software before. What is it and how does it apply
to the use of a VNA in general? Thanks in advance.
73, Tony VE3DWI.

On Wed, May 27, 2020 at 10:28 warnergt via groups.io <warnergt=
[email protected]> wrote:

I used to use Touchstone many, many years ago. It was a great program.
I haven't worked with S parameters for a long time so I'm out of touch
with the currently available applications.
What current applications work like Touchstone and/or work with Touchstone
files?
Re: Test fixture question

 

It looks wonderful, Just a tip

In my experience with this type of test jigs, when using the transformer configuration it is better to add some attenuation at the input and output (3-6 dB), this produces a better match to 50 Ohm when the crystal is not at exactly its series resonance, and the accuracy is improved.

I think that it can be done in your PCB as it is.

El 27/05/2020 a las 6:19, Bill Buoy escribi¨®:
Test fixture progress update:
The prototype boards arrived late last week. The components had arrived the week before, so between Memorial Day visits with the family and watching the local events, I built three versions over the weekend that I think will fit in with my immediate plans.
Testing with three crystals that I had on hand produced results as expected. The crystals were tested in the two versions that are targeted to that task. One version was built with a resistive attenuators to match the 50 ohm VNA impedance to 12.5 ohms. The other version uses a 4:1 balun on each side of the crystal to match the output and input of theVNA.
Assembly of the devices revealed a couple of changes to make assembly easier or accommodate easier parts selection. I will incorporate these changes, regenerate the production files, and resubmit for estimates. I plan to finish this and have answers by next week.
To accommodate the greatest number of people interested in this, I think the best way to release the files is to make the project public on Osh Park, publish the files here, and on my personal website.

--
El software de antivirus Avast ha analizado este correo electr¨®nico en busca de virus.
What apps use Touchstone files? #applications

[email protected]
 

I used to use Touchstone many, many years ago. It was a great program.
I haven't worked with S parameters for a long time so I'm out of touch with the currently available applications.
What current applications work like Touchstone and/or work with Touchstone files?
Re: Review of S-A-A-2 #nanovna-v2

[email protected]
 

Hello Luis,

yes, with battery in place. That's why I was worried that it will drain it. But after a few seconds the LEDs went off anyway. This makes me wait each time before putting it into the box - I guess I am a little like the Scottish guy, who didn't believe that the refrigerator light goes off, when you close the door :-)

For me, the portability and "groundlessness" are a big plus, so the battery is essential.

My intention was not additional shielding, just thought about FR4 because it is so easy to make a box by simple soldering. But in my experience, RF circuits often start to misbehave, when you put them into a metal box. Boxes have resonances, increasing the crosstalk between distant parts of the PCB, that's why metal boxes for RF circuits are in most cases subdivided into small compartments, often stuffed with absorber foam.

How did the 3D printed box come out? The little buttons, USB connector accessibility? SMA connectors fixed with nuts?

Marko Cebokli
Re: Test fixture question

 

Looks very good !


Op 27-5-2020 om 06:19 schreef Bill Buoy:

Test fixture progress update:
The prototype boards arrived late last week. The components had arrived the week before, so between Memorial Day visits with the family and watching the local events, I built three versions over the weekend that I think will fit in with my immediate plans.
Testing with three crystals that I had on hand produced results as expected. The crystals were tested in the two versions that are targeted to that task. One version was built with a resistive attenuators to match the 50 ohm VNA impedance to 12.5 ohms. The other version uses a 4:1 balun on each side of the crystal to match the output and input of theVNA.
Assembly of the devices revealed a couple of changes to make assembly easier or accommodate easier parts selection. I will incorporate these changes, regenerate the production files, and resubmit for estimates. I plan to finish this and have answers by next week.
To accommodate the greatest number of people interested in this, I think the best way to release the files is to make the project public on Osh Park, publish the files here, and on my personal website.
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