Le 02/03/2012 05:13, Neville Michie a écrit :
A possible solution is to take mean time (from a TBolt 10MHz) and
divide it by 9,972,695.7 to give a PPS(sid) signal that can run a
digital clock dial and give one second(sid) ticks to phase the
pendulum. It may be simpler to divide by 9,972,696 to stay with
integer division and have an error in the order of a second per annum.
(which we have from leap seconds anyway).
TVB made some picDIV chips with a synch pin that do a similar task,
but have I got the number correct?
number looks ok , at least according to the usual sources.
and are there other nuts that would like to add a sidereal clock to
their clock vaults to make it worth while to make such a chip?
Yup, I guess that would be a useful extension to the code. You would
just need to change the delays to fit a 2493174 instruction count for a
10MHz input.
If I set up the sidereal clock then I can use my theodolite to check
time against the stars.
More of a challenge I think. Harrison is reported to have used
occultation by buildings from a known observation point. It would be
probably be easier than keeping a theodolite precisely orientated over
long periods of time.
cheers,
Neville Michie
Sydney
Australia
_______________________________________________
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.
