开云体育

On Mon, 13 Jan 2020 at 17:39, Leif M <sala.nimi@...> wrote:

I found a place (manage button) where I am supposed to be able to take a
screenshot from VNA but that was grayed.

Le lun. 13 janv. 2020 à 11:24, Alberto I2PHD <i2phd@...> a écrit :

========================
I tried to install nanovna-saver, the "post Christmas" release, under Linux Debian Buster, following the suggestions
given in this forum in previous messages, but to no avail...
This is the error message that I get :

==================

adb@debian:~/nanovna-saver$ sudo python3.7 -m pip --no-cache-dir install .
Processing /home/adb/nanovna-saver
Collecting PyQt5 (from NanoVNASaver==0.2.2)
Downloading

(3.2MB)
100% |████████████████████████████████| 3.2MB 4.9MB/s
Installing build dependencies ... done
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-install-8dms8p33/PyQt5/setup.py'

----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-install-8dms8p33/PyQt5/

==================

I am far from being a Linux expert, so am in bad need of suggestions and advice...

Thanks

--
/*73 Alberto I2PHD*
<<< >>>/

On 1/13/2020 4:47 AM, Rune Broberg wrote:

Hi Aldo,
thanks for reporting the bug. If possible, please try starting the
application from a command prompt (cmd.exe), and copy or screenshot the
error message that turns up in that window after the crash. This will
pinpoint exactly where the error lies.

I will try to look at it as soon as I can. :-)

On Mon, 13 Jan 2020 at 17:27, Leif M <sala.nimi@...> wrote:

Thanks. I found lS11l and S11 phase plot now allright. It would be nice to
see those in markers too.

On 13-1-2020 15:40, Dale Parfitt wrote:

Unfortunately, what you all are describing is a transformer and not a balun. The primary purpose of baluns and ununs is to attenuate common mode currents. This cannot be done on a single core other than 1:1. And even then, the discussion should be centered on the rejection of common mode current in your particular implementation.

Dale W4OP

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Gert Gremmen
Sent: Monday, January 13, 2020 7:04 AM
To: [email protected]
Subject: Re: [nanovna-users] How to find the right ferrite toroid for a receiving antenna balun?

What you are looking for is a minimum loss situation.

All ferrites are the same but for Al value (always freq dependent) and
hysteresis losses. Any low loss ferrite will do for your balun once the
optimum wire thickness and winding number is achieved.

Low loss characterization would be easiest when doing a simple 1:1
transformer as all impedances remain (the same) 50 Ohm.

Than just characterize at your frequency of interest, the transfer value
as a skalar (no need here for complex measurements)

Then make a 9:1 balun (arbitrary N windings) and use a 400 ohm serial
resistor (to make sure it is loaded by 450 Ohm) to the input of the
nanoVNA (400 +50(input nano) = 450) to verify you were looking for.
Alternately you can reverse the measurement by inputting into the "9"
side + 400 and loading the "1" side. (Losses shall essentially be the
same, if not, set up problem)

Then connect the "1"side of the balun to your receiver (without 400 Ohm)
and characterize the "9" side for SWR and having a 450 Ohm real input.

(you might characterize the 400 ohm resistor first (to be
non-inductive) so as to make sure it does not spoil the measurement, and
allowing you to measure the transfer losses created by the resistor)

Once you found best ferrite you may experiment with winding numbers (to
cope for the specific Al value of your ferrite) and optimize the
transfer to your receiver. Experiments may be bifilar winding, other
geometries of the ferrite, (though you will find a correlation between
ferrite volume and losses,so keep it small) and winding variations and
interconnections. The last parts are the fun in this hobby.

If you do a good job, your balun may function from 300-30000 kHz. It is
difficult to have more than 1:100 in frequency range for a non tuneable
balun, due to non-symmetries in windings and interconnects.

My 1 cents.....

Gert

On 13-1-2020 12:06, ptapon@... wrote:

Hello everyone,

A newbie set of questions.

On the net, you have as many opinion, way of measuring etc. as you have pages with the word ferrite in it.
Moreover, they are too few discussion to how to characterize a ferrite with a VNA. Bunch of stuff for common mode chokes and the like, but not a lot for baluns
Given we have now a wonderful set of tools, NanoVNA and nanoVNA Saver, I'd like to understand how to make the right choice.

I'm only interested in receiving antennas, therefore no power will go through, no heating concerns etc.
I'm, for now, interested in HF bands with, for now, a long wire.
I'm therefore aiming for a 9:1 balun.
I have a bunch of "no names" ferrites in my junk drawer, some from power supply, therefore likely good for KHz ranges and others from various sources.
As many of us, amateurs, I tend to use what I have handy, and not building, from a web page, the, say, Fair-rite type 43 with 9 turns of 26 AWG, without "fully" understanding what I am doing.

My main question:
What will be the characteristics to look for when comparing ferrites - and choosing the best one- for a 0-30Mhz 9:1 balun?

I have built an enclosure with dual sided PCB and SMB connectors (from another junk drawer :-) ) with a 50R resistor at the input SMB.
Calibration is done with the enclosure. I'm using the same wire I will likely use for the balun, between the input and either the ground or another SMB connected to S2.

I have already zillions of NanoVNA saver screen shots with various ferrites but I'm unable to find the right info to make a decision.
Will it be from the smith chart, SWR, Z, return loss, ??

Is there a way to find the right ferrite without winding a 9:1 balun each time.

When testing a 9:1 balun:
Do I need to load the "output" of the balun with a 450R resistor?
Do I need to connect the output (loaded or not) to the S2 ?
If yes, what will be the right info to look for?

Any help or pointer to the right docs will be helpful.
Thanks in advance

Jean

On Mon, 13 Jan 2020 at 14:34, hwalker <herbwalker2476@...> wrote:

Rune,
Good to see you are back from the holidays. The ver 0.2.2 "Christmas
Update" is a welcome start to the New Year. I was waiting for your
announcement of its release on this forum, but after a day went by I let
the cat out of the bag for you.

Best Regards,

- Herb

On 13 Jan 2020 11:06 am, ptapon@... wrote:

Hello everyone,

A newbie set of questions.

On the net, you have as many opinion, way of measuring etc. as you have
pages with the word ferrite in it.
Moreover, they are too few discussion to how to characterize a ferrite
with a VNA. Bunch of stuff for common mode chokes and the like, but not a
lot for baluns
Given we have now a wonderful set of tools, NanoVNA and nanoVNA Saver, I'd
like to understand how to make the right choice.

I'm only interested in receiving antennas, therefore no power will go
through, no heating concerns etc.
I'm, for now, interested in HF bands with, for now, a long wire.
I'm therefore aiming for a 9:1 balun.
I have a bunch of "no names" ferrites in my junk drawer, some from power
supply, therefore likely good for KHz ranges and others from various
sources.
As many of us, amateurs, I tend to use what I have handy, and not
building, from a web page, the, say, Fair-rite type 43 with 9 turns of 26
AWG, without "fully" understanding what I am doing.

My main question:
What will be the characteristics to look for when comparing ferrites - and
choosing the best one- for a 0-30Mhz 9:1 balun?

I have built an enclosure with dual sided PCB and SMB connectors (from
another junk drawer :-) ) with a 50R resistor at the input SMB.
Calibration is done with the enclosure. I'm using the same wire I will
likely use for the balun, between the input and either the ground or
another SMB connected to S2.

I have already zillions of NanoVNA saver screen shots with various
ferrites but I'm unable to find the right info to make a decision.
Will it be from the smith chart, SWR, Z, return loss, ??

Is there a way to find the right ferrite without winding a 9:1 balun each
time.

When testing a 9:1 balun:
Do I need to load the "output" of the balun with a 450R resistor?
Do I need to connect the output (loaded or not) to the S2 ?
If yes, what will be the right info to look for?

Any help or pointer to the right docs will be helpful.
Thanks in advance

Jean

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Gert Gremmen
Sent: Monday, January 13, 2020 7:04 AM
To: [email protected]
Subject: Re: [nanovna-users] How to find the right ferrite toroid for a receiving antenna balun?

What you are looking for is a minimum loss situation.

All ferrites are the same but for Al value (always freq dependent) and
hysteresis losses. Any low loss ferrite will do for your balun once the
optimum wire thickness and winding number is achieved.

Low loss characterization would be easiest when doing a simple 1:1
transformer as all impedances remain (the same) 50 Ohm.

Than just characterize at your frequency of interest, the transfer value
as a skalar (no need here for complex measurements)

Then make a 9:1 balun (arbitrary N windings) and use a 400 ohm serial
resistor (to make sure it is loaded by 450 Ohm) to the input of the
nanoVNA (400 +50(input nano) = 450) to verify you were looking for.
Alternately you can reverse the measurement by inputting into the "9"
side + 400 and loading the "1" side. (Losses shall essentially be the
same, if not, set up problem)

Then connect the "1"side of the balun to your receiver (without 400 Ohm)
and characterize the "9" side for SWR and having a 450 Ohm real input.

(you might characterize the 400 ohm resistor first (to be
non-inductive) so as to make sure it does not spoil the measurement, and
allowing you to measure the transfer losses created by the resistor)

Once you found best ferrite you may experiment with winding numbers (to
cope for the specific Al value of your ferrite) and optimize the
transfer to your receiver. Experiments may be bifilar winding, other
geometries of the ferrite, (though you will find a correlation between
ferrite volume and losses,so keep it small) and winding variations and
interconnections. The last parts are the fun in this hobby.

If you do a good job, your balun may function from 300-30000 kHz. It is
difficult to have more than 1:100 in frequency range for a non tuneable
balun, due to non-symmetries in windings and interconnects.

My 1 cents.....

Gert

On 13-1-2020 12:06, ptapon@... wrote:

Hello everyone,

A newbie set of questions.

On the net, you have as many opinion, way of measuring etc. as you have pages with the word ferrite in it.
Moreover, they are too few discussion to how to characterize a ferrite with a VNA. Bunch of stuff for common mode chokes and the like, but not a lot for baluns
Given we have now a wonderful set of tools, NanoVNA and nanoVNA Saver, I'd like to understand how to make the right choice.

I'm only interested in receiving antennas, therefore no power will go through, no heating concerns etc.
I'm, for now, interested in HF bands with, for now, a long wire.
I'm therefore aiming for a 9:1 balun.
I have a bunch of "no names" ferrites in my junk drawer, some from power supply, therefore likely good for KHz ranges and others from various sources.
As many of us, amateurs, I tend to use what I have handy, and not building, from a web page, the, say, Fair-rite type 43 with 9 turns of 26 AWG, without "fully" understanding what I am doing.

My main question:
What will be the characteristics to look for when comparing ferrites - and choosing the best one- for a 0-30Mhz 9:1 balun?

I have built an enclosure with dual sided PCB and SMB connectors (from another junk drawer :-) ) with a 50R resistor at the input SMB.
Calibration is done with the enclosure. I'm using the same wire I will likely use for the balun, between the input and either the ground or another SMB connected to S2.

I have already zillions of NanoVNA saver screen shots with various ferrites but I'm unable to find the right info to make a decision.
Will it be from the smith chart, SWR, Z, return loss, ??

Is there a way to find the right ferrite without winding a 9:1 balun each time.

When testing a 9:1 balun:
Do I need to load the "output" of the balun with a 450R resistor?
Do I need to connect the output (loaded or not) to the S2 ?
If yes, what will be the right info to look for?

Any help or pointer to the right docs will be helpful.
Thanks in advance

Jean

--