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For those that want to do very accurate phase and frequency measurements, but are not willing or capable to buy a PhaseStation or Timepod, a new FW has been made available for the nanoVNA-H4 HW that converts it into a mix between a DMTD and PhaseStation.
Accuracy of phase measurements is better then 1e-12 / (Tau in seconds) and the device support sending the phase measurements over USB to programs like TimeLab or writing to an internal SD card for later analysis.
During testing and comparing to other frequency and phase measurement devices, the tinyPFA outperformed conventional frequency counters and delivered phase measurements identical to a PhaseStation when used above the noise floor.
A wiki containing all the information for creating and using your own tinyPFA can be found here:
A support forum is available in case you have questions regarding the operation of the tinyPFA or want to share results
As the FW is fairly new you can expect some bugs.
The nanoVNA-H4 HW does not have to be modified so after use as a tinyPFA, it can always be converted back into a VNA.
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On 22/12/2022 06:27, Erik Kaashoek wrote: For those that want to do very accurate phase and frequency measurements, but are not willing or capable to buy a PhaseStation or Timepod, a new FW has been made available for the nanoVNA-H4 HW that converts it into a mix between a DMTD and PhaseStation.
Accuracy of phase measurements is better then 1e-12 / (Tau in seconds) and the device support sending the phase measurements over USB to programs like TimeLab or writing to an internal SD card for later analysis.
During testing and comparing to other frequency and phase measurement devices, the tinyPFA outperformed conventional frequency counters and delivered phase measurements identical to a PhaseStation when used above the noise floor.
A wiki containing all the information for creating and using your own tinyPFA can be found here:
A support forum is available in case you have questions regarding the operation of the tinyPFA or want to share results
As the FW is fairly new you can expect some bugs.
The nanoVNA-H4 HW does not have to be modified so after use as a tinyPFA, it can always be converted back into a VNA. Erik, This looks very interesting. Are there any plans to support other nanoVNA class devices? Of course, the H4 is one I /don't/ have! A pity that you can't use groups.io as I /hate/ "forums". I want e-mail in and e-mail out, sigh! Yes, groups.io is [now] quite expensive. How about time-nuts, or would Tom consider it inappropriate? Thanks for making this available. Cheers, David -- SatSignal Software - Quality software for you Web: Email: david-taylor@... Twitter: @gm8arv
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Hi David,
This looks very interesting. Are there any plans to support other nanoVNA
class devices? Of course, the H4 is one I /don't/ have!
The design of the V2, Lite and Libre devices makes it impossible to use their HW in this way. And the MCU of the original nanoVNA-H is not fast enough so I gave up on that one.
A pity that you can't use groups.io as I /hate/ "forums". I want e-mail in and
e-mail out, sigh! Yes, groups.io is [now] quite expensive. How about
time-nuts, or would Tom consider it inappropriate?
Has been discussed with Tom and I agree with him. Giving support to a specific device does not fit with the time-nuts email list . I considered a simple email list but the absence of spam prevention tools requires moderation of every posted message and that is not something I want to do. Erik
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On 22/12/2022 11:19, Erik Kaashoek wrote: Hi David,
This looks very interesting. Are there any plans to support other nanoVNA
class devices? Of course, the H4 is one I/don't/ have! The design of the V2, Lite and Libre devices makes it impossible to use their HW in this way.
And the MCU of the original nanoVNA-H is not fast enough so I gave up on that one.
A pity that you can't use groups.io as I/hate/ "forums". I want e-mail in and
e-mail out, sigh! Yes, groups.io is [now] quite expensive. How about
time-nuts, or would Tom consider it inappropriate? Has been discussed with Tom and I agree with him.
Giving support to a specific device does not fit with the time-nuts email list .
I considered a simple email list but the absence of spam prevention tools requires moderation of every posted message and that is not something I want to do.
Erik Thanks, Erik. That rules out all the devices I have, then, unless the plain F might work! Noted on the support mechanism. I was thinking groups.io where you can easily moderate the first post, but the cost for a new group is prohibitive. Cheers, David -- -- SatSignal Software - Quality software for you Web: Email: david-taylor@... Twitter: @gm8arv
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On Thu, Dec 22, 2022 at 03:44 AM, David J Taylor wrote:
That rules out all the devices I have, then, unless the plain F might work!
No.
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On 12/21/22 10:27 PM, Erik Kaashoek wrote: For those that want to do very accurate phase and frequency measurements, but are not willing or capable to buy a PhaseStation or Timepod, a new FW has been made available for the nanoVNA-H4 HW that converts it into a mix between a DMTD and PhaseStation.
Accuracy of phase measurements is better then 1e-12 / (Tau in seconds) and the device support sending the phase measurements over USB to programs like TimeLab or writing to an internal SD card for later analysis.
During testing and comparing to other frequency and phase measurement devices, the tinyPFA outperformed conventional frequency counters and delivered phase measurements identical to a PhaseStation when used above the noise floor.
A wiki containing all the information for creating and using your own tinyPFA can be found here:
A support forum is available in case you have questions regarding the operation of the tinyPFA or want to share results
As the FW is fairly new you can expect some bugs.
The nanoVNA-H4 HW does not have to be modified so after use as a tinyPFA, it can always be converted back into a VNA.
This is all very cool. Do you have more info on the software you're loading into the NanoVNA? (I have a couple of the smaller screen versions).
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H version not have FPU and hardware DSP, and can lost samples in processing (very critical for phase) also have less flash size
This software - proof of concept for new device from Eric, and this concept work.
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On 22/12/2022 06:27, Erik Kaashoek wrote: For those that want to do very accurate phase and frequency measurements, but are not willing or capable to buy a PhaseStation or Timepod, a new FW has been made available for the nanoVNA-H4 HW that converts it into a mix between a DMTD and PhaseStation.
Accuracy of phase measurements is better then 1e-12 / (Tau in seconds) and the device support sending the phase measurements over USB to programs like TimeLab or writing to an internal SD card for later analysis. Just to clarify, I take it that it would not be possible to measure the offset and jitter between two 1 pps signals with the nanoPFA? Even if the levels were reduced to the -10/15/20 dBm level? The device isn't intended to measure time differences as such, or could it be? David -- SatSignal Software - Quality software for you Web: Email: david-taylor@... Twitter: @gm8arv
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Hi, Erik,
Thanks a lot for this new instrument, very cool to have such gear in a homelab!
Very impressive!
How do You think, what else could be done to further enhance the noise floor of the NanoPFM?
May be another internal clock used in Nano for the mCU would help? Have You already tried to do anything with it?
Best regards,
Alex
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Hi Alex,
The internal clock is not the issue as any impact of the internal clock is totally eliminated by the method used.
The nanoVNA-H4 uses a well balance system design where a number of design parameters are all chosen to support a certain performance.
If you want to further reduce the noise floor, much of the design will have to change and it will become MUCH more expensive.
Do you have an application where the current noise floor is a limitation?
Erik
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On Thu, Dec 22, 2022 at 11:01 PM, David J Taylor wrote:
it would not be possible to measure the offset and jitter between two 1 pps
signals with the nanoPFA? Even if the levels were reduced to the -10/15/20 dBm
level? The device isn't intended to measure time differences as such, or could
it be?
David, Correct. The tinyPFA is not a conventional frequency counter that measures from a start event to a stop event and counts the number of pulses. The tinyPFA measures the phase difference between the two input signals and it uses all information in the input wave forms to do this. This is the same method as used in the PhaseStation. But the PhaseStation does direct to digital using its 100MHz ADC's where the tinyPFA mixes the inputs down to its 192kHz ADC's. This difference in ADC speed explains the accuracy and dynamic range difference. Erik
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On 12/22/22 11:01 PM, David J Taylor via groups.io wrote: On 22/12/2022 06:27, Erik Kaashoek wrote:
For those that want to do very accurate phase and frequency measurements, but are not willing or capable to buy a PhaseStation or Timepod, a new FW has been made available for the nanoVNA-H4 HW that converts it into a mix between a DMTD and PhaseStation.
Accuracy of phase measurements is better then 1e-12 / (Tau in seconds) and the device support sending the phase measurements over USB to programs like TimeLab or writing to an internal SD card for later analysis. Just to clarify, I take it that it would not be possible to measure the offset and jitter between two 1 pps signals with the nanoPFA?? Even if the levels were reduced to the -10/15/20 dBm level?? The device isn't intended to measure time differences as such, or could it be?
David Probably what you want is the TAPR TICC - Measures the time between two 1pps, has time to digital converters to get "sub clock" measurements. Needs a 10 MHz input too.
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The TAPR TICC is a good example of a conventional time measurent using time to time-to-digital technology to reach an accuracy beyond what is possible with only very fast counters.
Counters may have up to 5ns or a bit better resolution. With modern T2D you get resolution down to 14ps. To compare, the phase measurement resolution of the tinyPFA with 1s measurement time can be down to 1ps. A PhaseStation goes below 100fs
Erik,
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Hi Erik,
Thank you for making this firmware available!
Is there a way to calibrate the reference by software?
There is no NULL A FREQ menu.
I installed the FW dated 2022-12-19.
Thank you again!
Best Regards
Alberto
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Will be released tomorrow
Erik
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On Fri, Dec 23, 2022 at 12:05 PM, Erik Kaashoek wrote:
Do you have an application where the current noise floor is a limitation?
Definitely, NOT! But what's about the mid-time range on ADEV (approximately after 10...100 s there is a noise bump, possibly caused by some internal drifts?) 1E-14 seems to be a long-term limit for ADEV measurements in this case, are there any means to improve it? -- Best regards, Alex
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Yes, there is a way to go get rid of this bump
Shall we move this subject to the tinypfa support forum as this subject is of interest for all future users.
Erik
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New FW announcement here:
Erik
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Just want to mention that it is awesome that I have suddenly a phase noise and ADEV analyser in house! Thanks for this christmas gift, Erik! Your work is awesome!
I use the Symmetricon/Microsemi occasionally and didn't know about the free available TimeLab, works even with Wine. This opens up a new world for the ambitious hobbyist.
Cheers
- Bonzo -
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On Fri, Dec 23, 2022 at 09:08 PM, Erik Kaashoek wrote:
Will be released tomorrow
Erik
Wonderful! Thanks!
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David J Taylor
Alberto
