TimeLab can show "mask" overlays on various plots. It comes with a set of ADEV masks for cesium clocks, derived from the manufacturer's specifications for those clocks. Those masks don't show up on MDEV plots, because the manufacturers don't provide MDEV specs. For the mathematicians out there: is there a way to convert ADEV specs into equivalent MDEV specs? If not, does anyone have good measured MDEV data on any of the popular cesium clocks? Cheers! --Stu

Hi, On 04/23/2016 02:54 AM, Stewart Cobb wrote: > TimeLab can show "mask" overlays on various plots. It comes with a set of > ADEV masks for cesium clocks, derived from the manufacturer's > specifications for those clocks. > > Those masks don't show up on MDEV plots, because the manufacturers don't > provide MDEV specs. > > For the mathematicians out there: is there a way to convert ADEV specs into > equivalent MDEV specs? > > If not, does anyone have good measured MDEV data on any of the popular > cesium clocks? The slopes of ADEV for the different noises can be converted to slopes in MDEV. It is the separation of white phase modulation and flicker phase modulation that doesn't go very well with ADEV, but works in MDEV, but if you ignore the flicker then you should be able to translate without too much difficulty. Good luck! Cheers, Magnus

Hi The intended purpose of MDEV was to supply a plot that looked the same as an ADEV plot *except* for separating flicker phase. To the extent they succeeded, you can use the same plot on either one. (and as long as flicker phase is not an issue). To the extent they failed, you are stuck. Bob > On Apr 23, 2016, at 12:58 AM, Magnus Danielson <magnus@rubidium.dyndns.org> wrote: > > Hi, > > On 04/23/2016 02:54 AM, Stewart Cobb wrote: >> TimeLab can show "mask" overlays on various plots. It comes with a set of >> ADEV masks for cesium clocks, derived from the manufacturer's >> specifications for those clocks. >> >> Those masks don't show up on MDEV plots, because the manufacturers don't >> provide MDEV specs. >> >> For the mathematicians out there: is there a way to convert ADEV specs into >> equivalent MDEV specs? >> >> If not, does anyone have good measured MDEV data on any of the popular >> cesium clocks? > > The slopes of ADEV for the different noises can be converted to slopes in MDEV. It is the separation of white phase modulation and flicker phase modulation that doesn't go very well with ADEV, but works in MDEV, but if you ignore the flicker then you should be able to translate without too much difficulty. > > Good luck! > > Cheers, > Magnus > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.

Hi again, On 04/23/2016 06:58 AM, Magnus Danielson wrote: > Hi, > > On 04/23/2016 02:54 AM, Stewart Cobb wrote: >> TimeLab can show "mask" overlays on various plots. It comes with a set of >> ADEV masks for cesium clocks, derived from the manufacturer's >> specifications for those clocks. >> >> Those masks don't show up on MDEV plots, because the manufacturers don't >> provide MDEV specs. >> >> For the mathematicians out there: is there a way to convert ADEV specs >> into >> equivalent MDEV specs? >> >> If not, does anyone have good measured MDEV data on any of the popular >> cesium clocks? > > The slopes of ADEV for the different noises can be converted to slopes > in MDEV. It is the separation of white phase modulation and flicker > phase modulation that doesn't go very well with ADEV, but works in MDEV, > but if you ignore the flicker then you should be able to translate > without too much difficulty. I realized that this was a little short description of what I was actually thinking. For each noise-form, there exists a formula for the amplitude of ADEV and MDEV given a certain amount of noise-level. By estimating the noise-level from the ADEV, the particular MDEV slope level can be concluded. Doing so for the noise-forms identified allows conversion from ADEV to MDEV, giving the assumption that white phase modulation noise and flicker phase modulation noise isn't separated but is dominated by white phase modulation noise. Not perfect, but good enough. The more scientifically correct matching of ADEV slopes would be to actually match AVAR, as these sum together as non-coherent noise power rather than coherent sine power. Matching on ADEV causes biases. Typically is a least-square matching used. Similarly is MVAR used rather than MDEV. It should be noted that the breakpoints between the different sloped in ADEV and MDEV is expected to differ, so direct translation of these is not recommended. Cheers, Magnus

Hi, Well, there is differences in level, there is tables for it, so while on the large scale they are close, they are not the same. Vernotte have a table of it in one of the PVAR articles for instance. Cheers, Magnus On 04/23/2016 02:15 PM, Bob Camp wrote: > Hi > > The intended purpose of MDEV was to supply a plot that looked the same as an ADEV > plot *except* for separating flicker phase. To the extent they succeeded, you can use > the same plot on either one. (and as long as flicker phase is not an issue). To the extent > they failed, you are stuck. > > Bob > >> On Apr 23, 2016, at 12:58 AM, Magnus Danielson <magnus@rubidium.dyndns.org> wrote: >> >> Hi, >> >> On 04/23/2016 02:54 AM, Stewart Cobb wrote: >>> TimeLab can show "mask" overlays on various plots. It comes with a set of >>> ADEV masks for cesium clocks, derived from the manufacturer's >>> specifications for those clocks. >>> >>> Those masks don't show up on MDEV plots, because the manufacturers don't >>> provide MDEV specs. >>> >>> For the mathematicians out there: is there a way to convert ADEV specs into >>> equivalent MDEV specs? >>> >>> If not, does anyone have good measured MDEV data on any of the popular >>> cesium clocks? >> >> The slopes of ADEV for the different noises can be converted to slopes in MDEV. It is the separation of white phase modulation and flicker phase modulation that doesn't go very well with ADEV, but works in MDEV, but if you ignore the flicker then you should be able to translate without too much difficulty. >> >> Good luck! >> >> Cheers, >> Magnus >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >