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Article #8989

Re: Sidereal Time Clock

#8989
From: Rob Fugina
Date: Sat, 15 Dec 1990 23:21
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In article <10633@uhccux.uhcc.Hawaii.Edu> ressler@galileo.ifa.hawaii.edu (Mike "IR" Ressler) writes:
>>>The clock has to count from 00:00:00 to 23:56:03, then reset back to zero.
>> Why 23:56:03?   Doesn't sidereal time use 24 hours and just lose 4 min/day?
>I'm glad someone caught this. Sidereal time is indeed at 24 thing, it's just
>that the hours are slightly shorter - 1.002737909 times shorter (23h 56m
>4.09053s to the sidereal day). You just need to design a normal 24 hour clock
>that uses a clock frequency shifted up by this amount. Very vague
>recollections say that someone actually made 1.002738 MHz crystals, but I have
>no idea who. Good luck.
>  Mike Ressler - Infrared Photon Jockey     ressler@galileo.ifa.hawaii.edu

Thank you for this information!  I was only going on what my roommate said,
and it's he who wants the clock.  It's not often that the correct way is
the easier way...

So, if I found a 1.002738MHz xtal, I would divide it by 1000000 to have
1Hz...so what do I use to divide by a million?  Six divide-by-tens?

Rob
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From: robf@mcs213f.cs.umr.edu (Rob Fugina)
Newsgroups: sci.electronics
Subject: Re: Sidereal Time Clock
Message-ID: <1869@umriscc.isc.umr.edu>
Date: 15 Dec 90 23:21:04 GMT
References: <1833@umriscc.isc.umr.edu> <1990Dec12.214854.19076@swbatl.sbc.com> <10633@uhccux.uhcc.Hawaii.Edu>
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