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But I only have one unit, and I would like to know if there is an easy way - ie, without an oscilloscope etc - to measure the transmission loss through a unun.

Probably the best inexpensive technique would be using back-to-back or tandem identical devices.

The back-to-back system allows use of 50-ohm meters at each end, or S21 and S12 measurements with network analyzers, for loss and mismatch errors.

Taking half the measured loss through two identical devices can get us very close to the real loss.

On Wed, 20 May 2020 10:01:05 -0700, you wrote:

Hello team,

Is there an easy way to measure balun loss, without another one in tandem S11-S21 ?

I only have one and I would like to have its characteristics, including loss.

Cheers and thanks in advance.

Luís CT2FZI

What do you mean by "without another one in tandem"?

OE8UWW

MFJ is selling a set and that is good enough for HF and the tolerances are good enough for every day "hobby" work. I always lol at people promoting commercial calibration standards costing hundreds if not thousands of dollars for what I consider a piece of equipment just a notch over a toy.A useful toy but by no means high enough grade to spend a fortune on the accessories.

Hello team,

Is there an easy way to measure balun loss, without another one in tandem S11-S21 ?

I only have one and I would like to have its characteristics, including loss.

Cheers and thanks in advance.

Luís CT2FZI

Thanks to all who had suggestions on this matter.

Larry, K4MLA

I got mine from Mirfield Electronics, you could also try Canny Components.

Ian

If you want to build your own BNC calibration standard, OZ7OU has some detailed info at

Phase measurement on the reference line. At a frequency of 600 MHz, it is very accurate, at a frequency of 1250 MHz a slight discrepancy.
For information to the group.

Only good to 600MHz though.

--
Terry VK5TM
( )

NanoVNA need ~1-2ms for measure 1 point
Pause 0.5ms between measure points for wait si5351 freq lock (can be larger on band change)

Did a search on google using "bnc calibration kit" and had several hits that includes both male and female configurations along with a wide range of cost.

--
David S

One caveat to measuring at the end of a long cable is that the calibration and measurement may need to have the sweep speed reduced. A round trip reflection cal or measurement with a 100 M transmission line with a velocity factor of .66 will be roughly a microsecond.
This can be controlled on a commercial VNA - I'm not sure if the nanovna / saver has that capability.

Bob

Hello all-

received my nanoVNa from Amazon Sunday, have the Saver software running on
win10 ok.

Trying to also install on Ubuntu 18.04, but run into problems:

~/nanovna-saver$ python3.7 -m pip install .
Processing /home/dandell/nanovna-saver
Collecting PyQt5 (from NanoVNASaver==0.2.2)
Using cached

Complete output from command python setup.py egg_info:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/usr/lib/python3.7/tokenize.py", line 447, in open
buffer = _builtin_open(filename, 'rb')
FileNotFoundError: [Errno 2] No such file or directory:
'/tmp/pip-build-dnr2o492/PyQt5/setup.py'
Error in sys.excepthook:
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63,
in apport_excepthook
from apport.fileutils import likely_packaged, get_recent_crashes
File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in
<module>
from apport.report import Report
File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in
<module>
import apport.fileutils
File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23,
in <module>
from apport.packaging_impl import impl as packaging
File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line
24, in <module>
import apt
File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in
<module>
import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'

Original exception was:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/usr/lib/python3.7/tokenize.py", line 447, in open
buffer = _builtin_open(filename, 'rb')
FileNotFoundError: [Errno 2] No such file or directory:
'/tmp/pip-build-dnr2o492/PyQt5/setup.py'

------------------------------
i have also checked to see if the other Python modules are installed and
they are

(You may need to install the additional packages python3-distutils,
python3-setuptools and python3-wheel for this command to work on some
distributions.)

any help out there?

Thanks Dan KC2STA

--
Dan Ziolkowski KC2STA
SKCC #4290T
Ubuntu LINUX

Don't know whereabouts you are.

I bought my nanoVNA-H from Mirfield Electronics here in the UK. Arrived in 4 days, well packed and included a couple of extras adapters for PL259/SO239 in the price. Satisfied customer.

I see that Passion Radio in France advertises the H model for 65 Euros.

A quick search should find both.

Chris

IN France, we have

In France we have,

Can you name them and/or give their website URLs?

I have been using Aramex Global Shopper (I'm normal client of the company) for the last 3 years - I provide an address in Hongkong for AliExpress and the shipment took 10 days to arrive there from Mainland China. Then it is another 10 days to my door in Pretoria, South Africa.

In this case I realised that I have a NanoVNA V3.1 Hardware (White Plastics) and decide I need a upgraded (V3.4). A bigger screen would be nice and with the support given by DisLord for this version, I decided on a -H4 from the Deepelec store on AliExpress.

Hope to have it in a few days. The shipping per courier adds $10-$20, but it is worth it given the Covid issues

Mike - That's been going on for 12+ months - I buy from China regularly and have been on several occasions. Generally there's no problems with the stuff leaving the factory but the distribution centres in Hong Kong are a different matter. See - some of my suppliers are now shipping via other centres. Covid just added to the inefficiency excuses.