If you are going to do that computation, HP has a Digital Display (59304A) for the GPIB in the very same family of instruments.
-John ================== > Sidereal Time is another form of Earth Orientation angle based time > where the orientation angle reference is the "fixed stars" instead of > the mean sun. > > You need to take such effects as precession, nutation and polar motion > into account. > The rate isn't uniform with respect to atomic time. > > The (rate) ratio of UT1 to mean sidereal time is defined to be > 0.997269566329084 â 5.8684Ã10â11T + 5.9Ã10â15T², where T is the > number > of Julian centuries of 36525 days each that have elapsed since JD > 2451545.0 (J2000). > > If you are using UTC broadcasts to determine Sidereal time, you first > need to correct UTC to obtain UT1 by applying the correction DUT1 ( UTC > -UT1). > DUT1 predictions etc are available from IERS. > > Bruce > > Neville Michie wrote: >> It is an interesting question, we are so used to WWV and GPS with >> regular time signals to synchronise clocks to mean solar time. >> One method is to get a pocket calculator to identify a time in the >> future when a siderial second nearly corresponds to a UTC second >> and use the PPS pulse from GPS to jam a preset time into the Siderial >> clock, (or start a halted clock with the correct time preset. >> How long you have to wait for corresponding seconds depends on how >> accurate you want it. >> cheers, Neville Michie >> >> >> >> On 15/01/2010, at 2:25 PM, Bruce Griffiths wrote: >> >>> Brian Kirby wrote: >>>> I would like to have an electronic clock to keep sidereal time. I am >>>> planning on using a HP 59309A, which can except an external clock of >>>> 1/5/10 Mhz. >>>> >>>> According to Wikipedia sidereal time is 23 hours 56 minutes and >>>> 4.091 seconds - a total of 86,164.091 seconds >>>> >>>> So 86,400 seconds for a normal "atomic defined" day divided by >>>> 86,164.091 = 1.002,737,903,89 >>>> >>>> If I set the 59309A to 10 Mhz external clock and dial a synthesizer >>>> up to 10.0273790, the unit should be able to keep sidereal time. >>>> >>>> Is my math and theory correct ? >>>> >>>> Brian - KD4FM >>>> >>> That just gives the rate. >>> How are you going to set the actual Sidereal time to better than the >>> 0.9s that can be deduced from UTC? >>> >>> Bruce >>> >>> >>> _______________________________________________ >>> 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. > > _______________________________________________ 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.
