Yes, all of those filter measurements would be useful for things I do.? Those functions would elevate you from "hero" to "demi-god" in my world.? :-)
Mike WY6K
"... somewhere in the distance, there's a tower and a light, broadcastin' the resistance, through the rain and through the night..."
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On Thursday, October 3, 2019, 4:20:50 AM CDT, Rune Broberg <mihtjel@...> wrote: Hi Norbert, the application can run calibrations at far more than 401 points - I have certainly done 5050 points at one point. ;-) But it does this in the application, and not on the device, due to the hardware limitations. I agree that a function to find cut-off frequencies for filters etc. would be interesting, and I've put it on the list of features I would like to implement for the next version, ie. for next week. I don't make any promises though :-) What measurements would be relevant to provide? Cut-off frequency, span for band-pass, dB/octave and dB/decade fall-off, pass-band ripple? -- Rune / 5Q5R On Thu, 3 Oct 2019 at 11:12, <norbert.kohns@...> wrote: Hi Rune,
thank you for fixing this issue!
I have a question for you in respect to the required number of data points
to measure a band pass filter. With 101 points it is most likely not
possible to find the -3 dB points because the sample point is way off from
-3 dB on both sides of the band pass. With 401 points it would work. An
automatic feature of measuring the bandwidth would be absolutely cool! The
TAPR software is able to perform a calibration at 401 points or even more
than that, so I am certain that you could do that as well.? I have no glue
on how difficult that would be, but more data points for calibration would
be a huge improvement.
Kind regards
Norbert, DG1KPN
|
Dr. David Kirkby from Kirkby Microwave Ltd
On Thu, 3 Oct 2019 at 09:53, Gerry Kavanagh via Groups.Io <gerrykav= [email protected]> wrote: Nice idea. I wonder how long those little u.fl connectors will last though. Hirose, the designer of the U.FL connector, says *20 matings. * IMHO, it would be cheaper and better to just get some chassis mount SMA connectors and assemble something oneself. eBay item 183574973423 has 5 SMA connectors at $2.80 delivered to the UK. * Opens can be made free. * Shorts can be made for the cost of a bit of solder.??? * Other devices can be made very cheaply. Working out the S-parameters If you look at the cost of that board, it is *much* more expensive than far more sophisticated PCBs available from China. To me at least, it seems a relatively large amount of money for something that has very little substance to it. SDR-KITS sell a test board that seems to offer much more room for experimentation at a better price. Dave -- 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
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I believe thay are rated for fewer than 10 insertions.
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NEW - Two-Trace Antenna Analyser (AA) Oct-3-19 firmware versions now available
Folks,
Hugen has built several up-to-date (as of Oct 3, 2019) versions of his Antenna Analyser (AA) firmware for the NanoVNA.
These have the thicker fonts that are easier to read.
The entire drive download is 20MB and contains a lot of older files, so you may want to only D/L what you need.
On the Google drive here:
bin, hex & dfu files:
NanoVNA-H__900_ch_20191003
NanoVNA-H__900_aa_20191003
NanoVNA-H__800_ch_20191003
NanoVNA-H__800_aa_20191003
|
Hi Rune
here you are!
73, Norbert, DG1KPN
|
Re: Firmware file size now smaller?
Great answer thanks. I think though this time I'll just get the 800 file because I do not need to analyze at 900 MHz (not even 800 really).
As everyone already knows, this little unit is amazing for the price. I've already convinced several friends in the area to buy one.
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Hello Norbert,
It looks good! The number of points setting is the (slightly convoluted)
"segments" setting, providing 101 points per segment. But since there's
been a lot of questions about it, maybe I will try to make it more obvious.
Could you send me the resulting S2P file for the bandpass filter? I need
some test data for making a filter analysis section ;-)
Thanks,
--
Rune / 5Q5R
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On Thu, 3 Oct 2019 at 13:56, <norbert.kohns@...> wrote: Hi Rune,
thanks for the hint! I tried it out right away and it works very well!
I have attached the plot of a 200MHz BP-Filter. The calibration is done
with full span and 8 segments. Now I can figure out the bandwidth manually.
One thing I would like to mention. For good reason the professional VNAs
have "number of point" settings of i.e. 101, 201, 301, 401, 801 and so on.
Could that feature be implemented in your software as well?
Kind regards
Norbert, DG1KPN
|
Re: Firmware file size now smaller?
Chinese fonts take up more room.
BTW - hugen has released the TWO TRACE 'AA' version of the latest firmware, located on the Google Drive below.
There are both 800MHZ and 900MHz versions.
Regards,
Larry
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On Thursday, October 3, 2019, 7:57:15 a.m. GMT-4, <biounit.mike@...> wrote:
On the Google drive here -
The firmware is now in folders (I do not think this was the case last week when I got the 900 version date 9/24). But, the old .dfu version of NanoVNA-H__900_ch_ was 129 kB, and now the new version is only 96 kB. Does this seem strange to anyone - is this correct that the size was decreased? What changed to cause that?
NanoVNA-H__900_ch_20190924.dfu Size: 129 kB
NanoVNA-H__900_ch_20191003.dfu Size: 96 kB
|
Firmware file size now smaller?
On the Google drive here -
The firmware is now in folders (I do not think this was the case last week when I got the 900 version date 9/24). But, the old .dfu version of NanoVNA-H__900_ch_ was 129 kB, and now the new version is only 96 kB. Does this seem strange to anyone - is this correct that the size was decreased? What changed to cause that?
NanoVNA-H__900_ch_20190924.dfu Size: 129 kB
NanoVNA-H__900_ch_20191003.dfu Size: 96 kB
|
Hi Rune,
thanks for the hint! I tried it out right away and it works very well!
I have attached the plot of a 200MHz BP-Filter. The calibration is done with full span and 8 segments. Now I can figure out the bandwidth manually.
One thing I would like to mention. For good reason the professional VNAs have "number of point" settings of i.e. 101, 201, 301, 401, 801 and so on. Could that feature be implemented in your software as well?
Kind regards
Norbert, DG1KPN
|
Re: errors of "error" models
28 : DERDEI : Use of Standalone [gnuplot] Instead of [maxima]
Hello,
Allow us, please, to confirm the interested Common User,
who already observed that is indeed redundant in this case,
since the use of [maxima], which is still buggy, after thirty-seven
37 years of development:
(software)
is limited to calls of [gnuplot], that is of tool, which is under
development and extremely fruitful in results, for thirty-three
33 years:
Hence, the direct use of [gnuplot] instead of [maxima] is
strongly possible, e.g. in the way we already use it in our work:
[tlnomiva] : Transmission Line Nominal Values without
Tolerance - from Cable Specifications and Technical
Data Sheets : /F/L/O/S/S/ for MS Windows:
Sincerely,
gin&pez@arg
28
|
I agree; with decent screen calibration
and an old Samsung Galaxy Note stylus,
I find device menus faster and easier
than any VNA software UI,
so use software mostly for data capture or TDR.
|
Probably not long.
I am sure there are much more robust connection options available but <$30 for a set of possible uses doesn't exactly seem that expensive (you could make your own of course) but I guess if want to check functionality might be an idea.
You got a nice smith chart blank on one side to photocopy and own use etc :-)
72
Dom
M1KTA
|
Re: edy555 design notes on CALIBRATION sets
Hi Jim - Oristo, reference your inductor measurement above, Could you explain how you conducted this test? I will try! Did you recal the NanoVNA at each of your measurement ranges? Yes. Your test fixture set up isn't really a broad range test fixture. Exactly, but I am not about to build a pcb with BNC connectors for each component to measure, and it is IMO not necessary for use below 150 MHz. Did you lock down the position of your test clips and leads? Not really, but did not rearrange things between CAL and measurements I don't remember reading if the Nano firmware stores one single point/frequency calibration value, several over the specified frequency range or 101 points. I don't recall reading that explicitly, but suppose that SPAN CALs are @ 101 points; don't know what happens with CW stimuli..? What did your 51 ohm resistor look like over the 0.1-900 Mhz range after the calibration? It had not occurred to me to measure (since I never use that range), but since you ask, it is easily done... ... and the answer is: messy and unstable for reactance: * with usual 34cm SMA-BNC pigtail, 49.9-50.0 Ohms, but 500 uF to 5nH (??) - hard to read, with values rapidly changing drastically perhaps a video would be better... * replacing 34cm with 3m LMR195 and recalibrating yields the same 49.9-50.0 Ohms, but 800uF to 63nH I suppose that 3m LMR195 Smith plot is cleaner because 3m separation between nanoVNA and DUT reduces stray signal pickup by untrimmed axial resistor leads. FWIW, at lower (and more reasonable) frequencies, measurements are more stable for moderate SPAN than CW stimuli.
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Re: Is my Nanovna broken?
Thanks for the segment suggestion Rune and those off line too, I don't think it was the segment issue. It seems the callibration data had somehow been borked and nothing was correct, once did the 'cal reset' over serial it came back to life again. Will, have to redo the calibration again obviously and see if it can hold the information.
The actual device on all traces without even connecting a pc was seeing the 2 billion value.
72
Dom
M1KTA
|
Hi Norbert,
For calibration within NanoVNA-Saver, setup the sweep first to be the span
you want calibrated - for example, 50k to 1500M. Then in the box labeled
"segments", enter how many segments (of 101 points each) you want - so
entering 50 would give you 5050 points (and take about a minute per sweep).
This is how more points than 101 are acquired for normal sweeps as well.
--
Rune / 5Q5R
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On Thu, 3 Oct 2019 at 11:59, <norbert.kohns@...> wrote: Hi Rune,
thank you very much for your quick answer!
Please tell me the trick where I can change the number of points prior to
calibration. I didn't find that yet.
I think the following measurements are relevant:
Band pass -3dB, -6dB, and -60dB bandwidth.
The same for bandstop.
To measure a low pass or a high pass filter: -3dB right down and -3dB left
down.
Kind regards
Norbert, DG1KPN
|
Hi Rune,
thank you very much for your quick answer!
Please tell me the trick where I can change the number of points prior to calibration. I didn't find that yet.
I think the following measurements are relevant:
Band pass -3dB, -6dB, and -60dB bandwidth.
The same for bandstop.
To measure a low pass or a high pass filter: -3dB right down and -3dB left down.
Kind regards
Norbert, DG1KPN
|
Hi Norbert,
the application can run calibrations at far more than 401 points - I have
certainly done 5050 points at one point. ;-) But it does this in the
application, and not on the device, due to the hardware limitations.
I agree that a function to find cut-off frequencies for filters etc. would
be interesting, and I've put it on the list of features I would like to
implement for the next version, ie. for next week. I don't make any
promises though :-)
What measurements would be relevant to provide? Cut-off frequency, span for
band-pass, dB/octave and dB/decade fall-off, pass-band ripple?
--
Rune / 5Q5R
toggle quoted message
Show quoted text
On Thu, 3 Oct 2019 at 11:12, <norbert.kohns@...> wrote: Hi Rune,
thank you for fixing this issue!
I have a question for you in respect to the required number of data points
to measure a band pass filter. With 101 points it is most likely not
possible to find the -3 dB points because the sample point is way off from
-3 dB on both sides of the band pass. With 401 points it would work. An
automatic feature of measuring the bandwidth would be absolutely cool! The
TAPR software is able to perform a calibration at 401 points or even more
than that, so I am certain that you could do that as well. I have no glue
on how difficult that would be, but more data points for calibration would
be a huge improvement.
Kind regards
Norbert, DG1KPN
|
Hi Rune,
thank you for fixing this issue!
I have a question for you in respect to the required number of data points to measure a band pass filter. With 101 points it is most likely not possible to find the -3 dB points because the sample point is way off from -3 dB on both sides of the band pass. With 401 points it would work. An automatic feature of measuring the bandwidth would be absolutely cool! The TAPR software is able to perform a calibration at 401 points or even more than that, so I am certain that you could do that as well. I have no glue on how difficult that would be, but more data points for calibration would be a huge improvement.
Kind regards
Norbert, DG1KPN
|
Re: Is my Nanovna broken?
Thanks Rune,
I'll try both options. BTW this is running Linux & Python 3.74 version at home, work is much earlier so will have to wait I guess until later. I get the same output with the previous versions.
Using putty I can get into it and it seems to be functioning. Used the putty/cli command to reset the calibration data 'cal reset' and it seems to function again, I get odd 2 billion results in the 4 traces though every now and then if try to alter frequency again.
72
Dom
M1KTA
|
WY6K Mike Watts
gin&pez@arg
Oristo
