Tangetially relevant; I made a "patch" for TimeLab to use the gap-free frequency measurement-mode for the 53230A, if anyone is interested. On Fri, Apr 3, 2015 at 4:34 PM, Tom Van Baak <tvb@leapsecond.com> wrote: > > There is probably a good explanation for the ADEV-level in standard > > (pi-counting?) reciprocal frequency counter mode as well as the roughly > > 1/sqrt(10) enhancement in ADEV when increasing the gate-time 10-fold. > > Anders, > > See the part the end that shows why averaging breaks ADEV: > http://leapsecond.com/pages/adev-avg/ > > > I collected the data with a simple program that just calls the "READ?" > function > > repeatedly, which does result in some dead-time between measurements. > > Yes, that's the easy way. But for more valid results use gap-free > continuous mode (SENS:FREQ:MODE CONT). From the manual: > > "CONTinuous configures the instrument to make continuous > resolution-enhanced, gap-free measurements. This mode should be selected > for true Allan deviation computation (CALCulate:AVERage subsystem). In > this mode, all samples for a each trigger are started by a single gate open > (instead of gate open/close per sample), and the measurements are computed > back-to-back with no dead time. CONTinuous can only be used for frequency > and average period measurements. Available only on the Agilent 53230A." > > /tvb > _______________________________________________ > 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. >

Ole Petter Ronningen: > Tangetially relevant; I made a "patch" for TimeLab to use the gap-free > frequency measurement-mode for the 53230A, if anyone is interested. Thanks for this great support! Ulli

I finally had time to compare the 53230A CONT (resolution-enhanced, aka lambda-counting) and RCON (undocumented! reciprocal continuous counting, aka pi-counting) modes, and wrote down some notes: http://www.anderswallin.net/2015/06/cont-vs-rcon-mode-on-the-53230a-frequency-counter/ comments on my notes, here or in the blog, are welcome. enjoy! Anders On Tue, Apr 7, 2015 at 9:42 PM, Mod Mix <modmix@t-online.de> wrote: > Ole Petter Ronningen: > >> Tangetially relevant; I made a "patch" for TimeLab to use the gap-free >> frequency measurement-mode for the 53230A, if anyone is interested. >> > Thanks for this great support! > Ulli > > _______________________________________________ > 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. >

Anders, Beware that there is both lambda and omega filterings on counters to enhance their performance over pi counters, and that this relates to frequency output. However, for propper ADEV and friends you have to be careful. TI-mode is to be used in order to avoid the lambda or omega properties. Enrico Rubiola and Francois Vernotte has made a number of publications on that subject. Cheers, Magnus On 06/24/2015 07:39 PM, Anders Wallin wrote: > I finally had time to compare the 53230A CONT (resolution-enhanced, aka > lambda-counting) and RCON (undocumented! reciprocal continuous counting, > aka pi-counting) modes, and wrote down some notes: > http://www.anderswallin.net/2015/06/cont-vs-rcon-mode-on-the-53230a-frequency-counter/ > comments on my notes, here or in the blog, are welcome. > > enjoy! > Anders > > On Tue, Apr 7, 2015 at 9:42 PM, Mod Mix <modmix@t-online.de> wrote: > >> Ole Petter Ronningen: >> >>> Tangetially relevant; I made a "patch" for TimeLab to use the gap-free >>> frequency measurement-mode for the 53230A, if anyone is interested. >>> >> Thanks for this great support! >> Ulli >> >> _______________________________________________ >> 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. >