OK, so my 2.5nS resolution is OK. Now I have to determine what level of average is best for the combination MV201/M12M and LPFRS/M12M.
On Tue, Oct 2, 2012 at 6:33 PM, Bob Camp <[email protected]> wrote: > Hi > > So to do things the "same way", start your time measurement at something > less than 1 ms and do the math to get to 1 second and beyond. One advantage > over the frequency reading would be that you will know what math has been > done. The math *does* very much matter.... > > Bob > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Tom Van Baak > Sent: Tuesday, October 02, 2012 9:39 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Best counter setting for ADEV? > > Azelio, > > In frequency average mode the 53132A makes something like 200,000 > measurements per second, according to the manual. This is why the > instrument > does so well as a smoothed frequency counter. The resolution "gain" is some > fraction of sqrt(200000), subject to the normal caveats like the need for > independent samples. That's why these counters have reduced resolution when > the input frequency is too close a multiple/fraction of the timebase. > > Details on this technique (used also in the Pendulum CNT-9x counters): > > "New frequency counting principle improves resolution" > http://tycho.usno.navy.mil/ptti/ptti2005/paper67.pdf > > See also this fine presentation by Staffan Johansson: > http://www.npl.co.uk/upload/pdf/20060209_t-f_johansson_1.pdf > > Or, google for: continuous time-stamping frequency counter > > /tvb > > ----- Original Message ----- > From: "Azelio Boriani" <[email protected]> > To: "Discussion of precise time and frequency measurement" > <[email protected]> > Sent: Tuesday, October 02, 2012 5:30 AM > Subject: Re: [time-nuts] Best counter setting for ADEV? > > > > Hmm, the frequency mode sigma is the same as the TI mode sigma for > 200*tau. > > That is if I take the sigma at 200*tau from the TI mode I have the same > > figure of the frequency mode. Maybe the frequency mode 2 seconds sample > > time uses 100 averages per second. > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
