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Re: Cal-Kit Standards' Definitions

 

Hello Oristo
Yes just by using the Electrical delay, but there is always a but, the delay in a transmission line is frequency dependent and if the impedance is not precise 50 ohm we might have an impact too. You may also use a phase trace and observe at what frequencies the delay is constant for which the it goes horizontal along thee 0 degree phase line. Changing the delay setting you may find at which specific frequency it crosses 0 degree thus determining the delay at that frequency. Remember the Electrical delay assumes and ideal 50 transmission line so....
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af Oristo
Sendt: 4. oktober 2019 15:30
Til: [email protected]
Emne: Re: [nanovna-users] Cal-Kit Standards' Definitions

every user would need to compute a value for the delay, which would be
different for the value in the cal kit.
If I correctly interpret Kurt, then with appropriate software:
* attach an unterminated length of balanced transmission line
* interactively dial that delay so that Smith plot does not spiral inward
Markers disappear at different span

 

Hi Rune,
I just tested a SFZ450F ceramic filter. First I had set a span of 50kHz and I set 3 markers. Than I changed to 50kHz span and all the markers were gone. If you try to set a new marker in the S21 window the data of the marker appears but you won't see the marker in any of the plots.
Very strange.

Kind regards
Norbert, DG1KPN

SFZ450F span 50MHz.jpg
SFZ450F span 20MHz.jpg
SFZ450F span 20MHz.s2p
SFZ450F span 20MHz.s2p
SFZ450F span 50MHz.s2p
SFZ450F span 50MHz.s2p

Re: Return Loss

 

What "a can of worms" this subject opens up.?I noticed the Hewlett Packard rarely if ever referred to return loss as a hardware specification; it was always specified in terms of SWR. Personally I prefer using return loss, with a negative sign. I know this results in misunderstandings, such as referring to a low SWR wideband antenna as having a low return loss. IEEE uses the negative return loss as a standard for their publications. I suppose that correct or not, the most used sign (negative) has became the standard. As long as we are all on the same page, it tends to work out.?All of my network analyzers will output either SWR or return loss, and an iPhone app will convert from one standard to the other.

Stuart K6YAZLos Angeles, USA

-----Original Message-----
From: Dr. David Kirkby from Kirkby Microwave Ltd <drkirkby@...>
To: nanovna-users <[email protected]>
Sent: Fri, Oct 4, 2019 12:55 pm
Subject: Re: [nanovna-users] Return Loss

Yes, I am G8WRB.

The problem is return loss is *often* used as a negative number in
professional academic publications. This one from an IEEE, has a
particularly amusing title;

Low-Return-Loss Printed Log-Periodic Dipole Antenna

Published in
IEEE Antennas and Wireless Propagation Letters
<>
( Volume: 13 )
Page(s)
503 - 506
ISSN Information
INSPEC Accession Number
14195004
DOI
10.1109/LAWP.2014.2310057 <>
Publisher:
IEEE
Sponsored by
IEEE Antennas and Propagation Society <>




and another, not published by the IEEE,


and another



As such, whilst I will continue to use a positive for all passive and most
active components, I really have no appetite for changing the mind of
others.



On Fri, 4 Oct 2019 at 20:26, Reinier Gerritsen <r.gerritsen@...>
wrote:

return loss is (almost always) a positive number. If one insists on
negative numbers, just call it s11 (or s22). In essence the same
property, but negative.

Op 4-10-2019 om 17:20 schreef Ron Spencer via Groups.Io:
I read a recent post that said that, among hams, its become the
consensus that return loss is a negative number. I respectfully disagree.



Regarding return loss, I understand some think its a negative number,
some a positive. I am in the later camp. Why? When I was a young engineer I
had the great fortune, in the early 1980s, to work for HP. Arguably the
premier test and measurement company of its time. And equally arguably a
leading if not THE leading microwave and rf company.



As new sales people, we were sent to 3, 3 week training sessions to
learn the technology and the products so we might interact with our
engineering customers in a technically sound way.



One thing HP taught, as I've said in a much earlier post, was that
return loss was always a positive number. As someone on this list pointed
out, negative loss is gain. And we KNOW that no return loss measurement, of
a passive device, can exhibit gain.



With respect, there is no gray area here. Return loss, is always a
positive (or, perhaps better said, a non- signed) number.


Even if you are at a hobby level of involvement, why not use the proper,
and correct, terminology? If you're a private pilot, you are expected/
required to use the proper terminology. Same if you are an amateur road
racer. Or "fill in your favorite" hobby.













Sent using





--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom
Re: Another ebay deal?

 

Another option, If you want to plot smith charts from Touchstone .s1p .s2p files, Simsmith also does this. It is Free. <>
I am eagerly hoping someone integrates this new nanoVNA to output document format like Simsmith, and Zplots type functionality. <> Right now, all we have is screen captures.

Thanks,
David
W0IM

-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Dr. David Kirkby from Kirkby Microwave Ltd
Sent: Thursday, October 3, 2019 4:24 PM
To: nanovna-users <[email protected]>
Subject: Re: [nanovna-users] Another ebay deal?
Do you have any gnuplot code which can import a Touchstone file and
plot
it on the Smith Chart? I produce all my plots for VNA cal kits usin gnuplot, as one can automate everything, reducing the risk of errors. But I have never plotted it on a Smith Chart - only amplitude and phase on the same graph, using two y-axes,
Re: Supply voltage requirement?

 

The internal LiOn battery (if connected) is like 3.7 to 4.2V. It is normally charged from externally-supplied USB 5V. This suggests to me that the innards run on something less than 3.7V (most likely 3.3V), meaning that there is an on-board voltage regulator to drop 5V to whatever the internals run on.

My question has to do with what is the maximum voltage that the internal voltage regulator can handle. If doing this, there would be no internal LiOn battery.
Re: NanoVNA V2

 

You must have a very cheap source of the ADF4350 since MAX2871 is just around 8 USD.
Which RF switch do you use to switch between the si5351 and the ADF4350? Most switches are not specified below a few tens of MHz.
I'm looking for a cheap one!
Thanks, Reinier

Op 4-10-2019 om 17:41 schreef Gabriel Tenma White:

Lower frequency limit: will be unchanged because the si5351 is still present and is switched in below 140MHz.

Larger screen: we are going to use the plug-in style of ILI9341 display rather than the bare FPC version because this board has components on both sides, so the 3.5 inch ILI9341 display is drop in compatible (provided you buy one with the correct pinout). Size beyond 3.5inch is not currently doable because 3.5inch is the largest SPI LCD size available. Larger displays (for example on the NanoVNA-F) use a parallel interface with far more pins which will require a larger MCU, adding many dollars of cost.

MAX2871: unfortunately this costs about 30 times the ADF4350, so isn't doable for the base version.

IAM-81008: that's a nice part, cheaper than the AD8342 and less power consumption. We might evaluate it and see if it will give acceptable performance. The IIP3 is much lower though, which means it has to be operated at lower signal levels to avoid bad linearity.

Open source: the schematic will be posted as soon as the product is generally available.

In the longer term we may introduce a higher end VNA. However the bigger priority there is full two port support - measuring all 4 S parameters at once. This is more aimed at lab use, so we may just remove the screen altogether (it's a big cost adder and a nuisance for shipping and firmware development) and have only a USB and wireless user interface.
Re: Preamp noise figure (NF) measurement?

 

Could always try! But it's not first on the wishlist. I'll keep this thread
linked on the backlog :-)

--
Rune / 5Q5R

On Fri, 4 Oct 2019 at 22:13, Larry Rothman <nlroth@...> wrote:

so - this is something that Rune might be able to add to his 'Saver
application?

On Friday, October 4, 2019, 3:32:44 p.m. GMT-4, erik@... <
erik@...> wrote:

From my limited understanding of the Y factor noise measurement you only
need to measure power ratio in a not so critical frequency band. Correct?
If yes. The CH1 input can function as a power meter with a not so we'll
defined bandpass filter
Sensitivity is limited by the noise factor of the SA or about 5 and
leakage from the SI5351
In console mode you can switch to measuring the CH1 power without the DSP
filter so you use the adc anti alias filter as band filter. It's basically
working as a direct conversion to DC receiver.
Re: Preamp noise figure (NF) measurement?

 

so - this is something that Rune might be able to add to his 'Saver application?

On Friday, October 4, 2019, 3:32:44 p.m. GMT-4, erik@... <erik@...> wrote:

From my limited understanding of the Y factor noise measurement you only need to measure power ratio in a not so critical frequency band. Correct?
If yes. The CH1 input can function as a power meter with a not so we'll defined bandpass filter
Sensitivity is limited by the noise factor of the SA or about 5 and leakage from the SI5351
In console mode you can switch to measuring the CH1 power without the DSP filter so you use the adc anti alias filter as band filter. It's basically working as a direct conversion to DC receiver.
Re: Return Loss

Dr. David Kirkby from Kirkby Microwave Ltd
 

Oops,
This was not meant to be sent to the list, but privately to someone who
emailed me on the subject.

Anyway, I stand by what I said
1) Return loss should be positive for passive components.
2) I have no desire to try to convince others to my way of thinking.

Dave

On Fri, 4 Oct 2019 at 20:55, Dr. David Kirkby <
drkirkby@...> wrote:

Yes, I am G8WRB.

The problem is return loss is *often* used as a negative number in
professional academic publications. This one from an IEEE, has a
particularly amusing title;

Low-Return-Loss Printed Log-Periodic Dipole Antenna

Published in
IEEE Antennas and Wireless Propagation Letters
<>
( Volume: 13 )
Page(s)
503 - 506
ISSN Information
INSPEC Accession Number
14195004
DOI
10.1109/LAWP.2014.2310057 <>
Publisher:
IEEE
Sponsored by
IEEE Antennas and Propagation Society <>




and another, not published by the IEEE,


and another



As such, whilst I will continue to use a positive for all passive and most
active components, I really have no appetite for changing the mind of
others.



On Fri, 4 Oct 2019 at 20:26, Reinier Gerritsen <r.gerritsen@...>
wrote:

return loss is (almost always) a positive number. If one insists on
negative numbers, just call it s11 (or s22). In essence the same
property, but negative.

Op 4-10-2019 om 17:20 schreef Ron Spencer via Groups.Io:
I read a recent post that said that, among hams, its become the
consensus that return loss is a negative number. I respectfully disagree.



Regarding return loss, I understand some think its a negative number,
some a positive. I am in the later camp. Why? When I was a young engineer I
had the great fortune, in the early 1980s, to work for HP. Arguably the
premier test and measurement company of its time. And equally arguably a
leading if not THE leading microwave and rf company.



As new sales people, we were sent to 3, 3 week training sessions to
learn the technology and the products so we might interact with our
engineering customers in a technically sound way.



One thing HP taught, as I've said in a much earlier post, was that
return loss was always a positive number. As someone on this list pointed
out, negative loss is gain. And we KNOW that no return loss measurement, of
a passive device, can exhibit gain.



With respect, there is no gray area here. Return loss, is always a
positive (or, perhaps better said, a non- signed) number.


Even if you are at a hobby level of involvement, why not use the
proper, and correct, terminology? If you're a private pilot, you are
expected/ required to use the proper terminology. Same if you are an
amateur road racer. Or "fill in your favorite" hobby.













Sent using





--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT,
United Kingdom
--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom
Re: Return Loss

Dr. David Kirkby from Kirkby Microwave Ltd
 

Yes, I am G8WRB.

The problem is return loss is *often* used as a negative number in
professional academic publications. This one from an IEEE, has a
particularly amusing title;

Low-Return-Loss Printed Log-Periodic Dipole Antenna

Published in
IEEE Antennas and Wireless Propagation Letters
<>
( Volume: 13 )
Page(s)
503 - 506
ISSN Information
INSPEC Accession Number
14195004
DOI
10.1109/LAWP.2014.2310057 <>
Publisher:
IEEE
Sponsored by
IEEE Antennas and Propagation Society <>




and another, not published by the IEEE,


and another



As such, whilst I will continue to use a positive for all passive and most
active components, I really have no appetite for changing the mind of
others.



On Fri, 4 Oct 2019 at 20:26, Reinier Gerritsen <r.gerritsen@...>
wrote:

return loss is (almost always) a positive number. If one insists on
negative numbers, just call it s11 (or s22). In essence the same
property, but negative.

Op 4-10-2019 om 17:20 schreef Ron Spencer via Groups.Io:
I read a recent post that said that, among hams, its become the
consensus that return loss is a negative number. I respectfully disagree.



Regarding return loss, I understand some think its a negative number,
some a positive. I am in the later camp. Why? When I was a young engineer I
had the great fortune, in the early 1980s, to work for HP. Arguably the
premier test and measurement company of its time. And equally arguably a
leading if not THE leading microwave and rf company.



As new sales people, we were sent to 3, 3 week training sessions to
learn the technology and the products so we might interact with our
engineering customers in a technically sound way.



One thing HP taught, as I've said in a much earlier post, was that
return loss was always a positive number. As someone on this list pointed
out, negative loss is gain. And we KNOW that no return loss measurement, of
a passive device, can exhibit gain.



With respect, there is no gray area here. Return loss, is always a
positive (or, perhaps better said, a non- signed) number.


Even if you are at a hobby level of involvement, why not use the proper,
and correct, terminology? If you're a private pilot, you are expected/
required to use the proper terminology. Same if you are an amateur road
racer. Or "fill in your favorite" hobby.













Sent using





--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom
Re: Preamp noise figure (NF) measurement?

 

From my limited understanding of the Y factor noise measurement you only need to measure power ratio in a not so critical frequency band. Correct?
If yes. The CH1 input can function as a power meter with a not so we'll defined bandpass filter
Sensitivity is limited by the noise factor of the SA or about 5 and leakage from the SI5351
In console mode you can switch to measuring the CH1 power without the DSP filter so you use the adc anti alias filter as band filter. It's basically working as a direct conversion to DC receiver.
Re: Return Loss

 

return loss is (almost always) a positive number. If one insists on negative numbers, just call it s11 (or s22). In essence the same property, but negative.

Op 4-10-2019 om 17:20 schreef Ron Spencer via Groups.Io:

I read a recent post that said that, among hams, its become the consensus that return loss is a negative number. I respectfully disagree.



Regarding return loss, I understand some think its a negative number, some a positive. I am in the later camp. Why? When I was a young engineer I had the great fortune, in the early 1980s, to work for HP. Arguably the premier test and measurement company of its time. And equally arguably a leading if not THE leading microwave and rf company.



As new sales people, we were sent to 3, 3 week training sessions to learn the technology and the products so we might interact with our engineering customers in a technically sound way.



One thing HP taught, as I've said in a much earlier post, was that return loss was always a positive number. As someone on this list pointed out, negative loss is gain. And we KNOW that no return loss measurement, of a passive device, can exhibit gain.



With respect, there is no gray area here. Return loss, is always a positive (or, perhaps better said, a non- signed) number.


Even if you are at a hobby level of involvement, why not use the proper, and correct, terminology? If you're a private pilot, you are expected/ required to use the proper terminology. Same if you are an amateur road racer. Or "fill in your favorite" hobby.













Sent using

Re: Supply voltage requirement?

 

I think folks here are reporting 2-4 hours depending on the size and age of battery.I hear units come with 300mAH up to 450mAH batteries.? YMMV

On Friday, October 4, 2019, 3:09:04 p.m. GMT-4, Bob Albert via Groups.Io <bob91343@...> wrote:

How much run time should I expect from the standard battery?
? ? On Friday, October 4, 2019, 11:46:33 AM PDT, Larry Rothman <nlroth@...> wrote:

? Mike - Don't use anything else!

The NanoVNA was designed to use only a 5V supply, via the USB port.
The internal charge IC is both a 3.7V LiIon charger and 5V inverter combo - there are lots of comments about that chip on the forum.
The 5V output from that inverter MUST be well regulated as it supplies the mixer (612) chips.
If you want? longer run time - get a bigger Lithium battery. Do NOT use anything else or you'll damage stuff.
I used one from a cellphone that was 1100mAH - it WILL charge - but will take longer.


? ? On Friday, October 4, 2019, 2:30:19 p.m. GMT-4, mike miniver <wa7ark@...> wrote:

Is there an on-board voltage regulator that converts 5.0V from the USB to whatever is used internally?

If so, what external voltage range could be used in lieu of 5.0V from USB (but through the USB connector) to power the nanoVna?

I'm thinking of 4 rechargeable NiMH cells which would be about 5.2V fully charged, and about 4.4V when they need to be recharged?

WA7ARK
Re: info update

 

Does DfuSe_Demo_V3.0.6_Setup.exe have 30-day work limitations? Yes or no?
No, "Demo" may be an historic artifact from the original author.
STM makes the software freely available to encourage use of its STM32 technology.

DMR-CLEAR_MEMORY_DFU.dfu is the only file I need to clear the memory?
Yes, but you need that only if some other firmware does not work after installation.

Shouldn't these other files be used ?:
Most folks do not install firmware for no reason.

DMR-color-tweak-sept.29.2019_DFU.dfu
Do you need to change trace colors?

DMR_FILL Flash with FF DFU.dfu
May be the same as DMR-CLEAR_MEMORY_DFU.dfu
It is for the same purpose, so not both.

DMR_M_10KHz_sept-13-19.dfu
Such as these were for enhancements, in this case 10KHz instead of 50KHz minimum.
I >>guess<< many enhancements are in Gen Hu Oct 2 firmware

DMR_nano-white-trace-test.dfu
Do you want white traces?
Re: Preamp noise figure (NF) measurement?

 

HOWEVER:
The frequency steps on the NanoVNA are quite large depending on the settings.
Now, with that said, maybe Rune can create an SA NanoVNA-Saver offshoot application that would perform multi-segmented scans with very small frequency steps?
Erik had replied to my suggestions in an earlier post regarding using this device as an SA.Any comments on Alan's idea?
Regards,Larry

On Friday, October 4, 2019, 3:00:11 p.m. GMT-4, alan victor <avictor73@...> wrote:

Hi Bruce.

I see no one replied so I will make some noise! Pun intended. What FUN.

Apparently some folks have considered placing the VNA into a spectrum analyzer (SA) mode. Hence, with some care you should be able to read noise power. If you precede the VNA with sufficient gain and a very low noise preamp, say below 1 dB, then the converted VNA as a SA could be used to measure the cold and hot state of a noise source. You can build a pretty decent noise source or find a used hp with an ENR of 15 dB. Then you can use the Y factor to find the NF of the DUT. This is a fun project.

GL, Regards, Alan
Re: Supply voltage requirement?

Bob Albert
 

How much run time should I expect from the standard battery?

On Friday, October 4, 2019, 11:46:33 AM PDT, Larry Rothman <nlroth@...> wrote:

Mike - Don't use anything else!

The NanoVNA was designed to use only a 5V supply, via the USB port.
The internal charge IC is both a 3.7V LiIon charger and 5V inverter combo - there are lots of comments about that chip on the forum.
The 5V output from that inverter MUST be well regulated as it supplies the mixer (612) chips.
If you want? longer run time - get a bigger Lithium battery. Do NOT use anything else or you'll damage stuff.
I used one from a cellphone that was 1100mAH - it WILL charge - but will take longer.


? ? On Friday, October 4, 2019, 2:30:19 p.m. GMT-4, mike miniver <wa7ark@...> wrote:

Is there an on-board voltage regulator that converts 5.0V from the USB to whatever is used internally?

If so, what external voltage range could be used in lieu of 5.0V from USB (but through the USB connector) to power the nanoVna?

I'm thinking of 4 rechargeable NiMH cells which would be about 5.2V fully charged, and about 4.4V when they need to be recharged?

WA7ARK
Re: Preamp noise figure (NF) measurement?

 

Hi Bruce.

I see no one replied so I will make some noise! Pun intended. What FUN.

Apparently some folks have considered placing the VNA into a spectrum analyzer (SA) mode. Hence, with some care you should be able to read noise power. If you precede the VNA with sufficient gain and a very low noise preamp, say below 1 dB, then the converted VNA as a SA could be used to measure the cold and hot state of a noise source. You can build a pretty decent noise source or find a used hp with an ENR of 15 dB. Then you can use the Y factor to find the NF of the DUT. This is a fun project.

GL, Regards, Alan
Re: info update

 

Thanks!
Re: Accuracy of calculated values - Nano VNA and Saver

 

Rudi,
thank you very much for your kind comments :-)

--
Rune / 5Q5R

On Fri, 4 Oct 2019 at 18:34, <reuterr@...> wrote:

Hello Run,

I like to use your program and I am very happy with it.
You try to realize feasible expansion requests during the program
development.
And all for free and for the three main operating systems. That's a great
achievement.
Thanks a lot for this.
The criticism of someone sitting on a high horse should not impress you.

73, Rudi DL5FA
Re: Accuracy of calculated values - Nano VNA and Saver

 

Hi David,
your suggestion of interfacing with the HP 8753 is certainly interesting! I
am going to have the code reworked at some point to accept more VNA types,
so an 8753 option isn't completely impossible. As of now, though, I have no
way I would be able to test it, and that's likely to block any progress
towards it for the foreseeable future. I wouldn't want to be releasing
software that I no way to verify was actually running.

There might be someone local who has one, but barring that, I don't think
I'll work on it for now :-)
--
Rune / 5Q5R

On Fri, 4 Oct 2019 at 15:10, Dr. David Kirkby from Kirkby Microwave Ltd <
drkirkby@...> wrote:

On Fri, 4 Oct 2019 at 13:55, Rune Broberg <mihtjel@...> wrote:


If there are any miscalculations in my software, I do what I can to
correct
them. I have not recently been made aware of any problems, and at no
point
by Owen. I hope that any of you would immediately contact me, should you
find errors in NanoVNA-Saver! :-)
I have not read the article by Owen, but I would agree on this single point
about return loss. But I never commented to you, as it is a subject of much
debate. If there was a very clear majorty for one convention or the other,
I would stay you should go with it, but there's not a clear majority, so
use whatever you want.

If I was to use your software, which I might well do, but m interest is in
portable use, without external software, I would probably recompile and
change the sign. My HP LCR meter allows one to display this R+jX think in
multiple formats. I could give them to you if you wanted, but again, you
know what space you have.

While I am sending you a message, there's something else I thought of that
could be of use to many people, but you might not want to get involved in,
so I did not bother. Your software could be useful to those of us with the
very popular HP 8753 series VNA. It would be good if you could support
reading from them too. The Python code to open a GPIB code and read from it
is about 5 lines long. Much of the other commands you use to set up a
NonVNA would have an equivalent in 8753.

--
Rune / 5Q5R

--
Dr David Kirkby Ph.D C.Eng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD,
Essex, CM3 6DT, United Kingdom.
Registered in England and Wales as company number 08914892

Tel 01621-680100 / +44 1621-680100
35661 - 35680 of 39685