Xref: utzoo sci.astro:2335 comp.dcom.modems:2052 rec.ham-radio:5229
Path: utzoo!attcan!uunet!husc6!uwvax!oddjob!mimsy!fred
From: fred@mimsy.UUCP (Fred Blonder)
Newsgroups: sci.astro,comp.dcom.modems,rec.ham-radio
Subject: Re: N.B.S. Time Service
Summary: I've got one
Keywords: Time Ticks
Message-ID: <12277@mimsy.UUCP>
Date: 1 Jul 88 21:08:35 GMT
References: <455@trane.UUCP> <303@macomw.ARPA> <56@stanton.TCC.COM>
Reply-To: fred@mimsy.umd.edu.UUCP (Fred Blonder)
Distribution: na
Organization: Computer Science Dept., U of Maryland, College Park, MD 20742
Lines: 36


	In article <56@stanton.TCC.COM> donegan@stanton.TCC.COM
				(Steven P. Donegan) writes:

	I came across a dos based time service program that used a
	Hayes modem to autodial the Naval Observatory in the Wash. DC
	area (I think) and retrieved the REAL time (plus/minus a second
	or so). If anyone knows of source for a similar program that I
	could port to my UNIX system I'd appreciate having it.

We've been running such a program, which I wrote, at U of M for over a
year now. It's written in C, and runs under Berkeley Unix. It consists
of a rather large dialer program -- the moral equivalent of 'cu' and
such -- and a few special-purpose programs, including the one for
talking to the Naval Observatory's clock, which can hang off the back
end. We have a single line in our crontab file which runs this once a
night.

The Naval Observatory is , by law, the time standard for the country,
so their clock is, by definition, absolutely correct. The
machine-readable clock they provide is accurate to within about 15
milliseconds. The phone number is (202) 653-0351. It answers at 1200
baud, even parity. There's no login sequence and you don't have to
respond to it, it just spits out alternating ascii asterisks and
strings of digits containing the julian date and the universal time.
The string of digits refers to the PRECEDING asterisk, not the next.
("At the tone, the time was . . . ")

If you want a copy of this whole package (the clock-setter is only part
of it) those of you on the internet can do an anonymous ftp to
mimsy.umd.edu and grab the file 'x.shar'. If you can't get it this way,
let me know and I'll try something more drastic.
-- 
					Fred Blonder (301) 454-7690
					uunet!mimsy!fred
					Fred@Mimsy.umd.edu