[time-nuts] M12 100 Hz vs. 1PPS measurements

[WarrenS]

Tom, 
This is great work and Information to see.
I do think that this will inspire, and make if not a giant leap, at least a small step to better GPSDO performance. 

1st question:
Does anyone have or can they tell me where to get a copy of the actual raw data Tom used for these plots?
http://www.leapsecond.com/pages/m12-adev/

The Link on his leapsecond site to the raw data seems to be missing.
www.LeapSecond.com/logs/ - Logbook and raw data (ask) 
A request to Tom, so far has gone unanswered.

2nd question 
Can anyone provide me with the filter formula or algorithm or any information 
regarding that is used by any of the better GPSDO units to calculate the ECV 
Dac output voltage.

I know about the simple basic 1st order averaging  filter used in some of the units, 
and the even more basic but effective over under check to increment / decrement 
an accumulator.  BUT it would seem to me there has got to be filters that give much 
better result than either of these available and being used out there.

Allan deviation (ADEV) and Modified Allan deviation (MDEV) 
http://www.mail-archive.com/time-nuts@febo.com/msg07211.html




I'm looking for just the basic formula used to process the phase error data before 
being applied to the DAC. I am not looking for anything secrete or with all the extra 
things some use to verify that the data is valid or appropriate before being applied 
or thrown away.

Thanks, for any information you can provide me.
WarrenS

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----- Original Message ----- 
From: "Tom Van Baak" <tvb at LeapSecond.com>
To: "Discussion of precise time and frequency measurement" <time-nuts at febo.com>
Sent: Friday, December 05, 2008 12:32 AM
Subject: [time-nuts] M12 100 Hz vs. 1PPS measurements


>I know a number of you have been waiting for the results of
> this M12 experiment. I compared the performance of a 100 Hz
> output vs. a 1PPS output vs. a 1PPS with sawtooth correction.
> 
> http://www.leapsecond.com/pages/m12-adev/
> 
> I think it came out quite well and it may surprise some of you.
> 
> /tvb
> 
> 
> 
> 
>