[ntp:questions] Meinberg NTP Software--Time Accuracy
David J Taylor
david-taylor at blueyonder.not-this-part.nor-this.co.uk.invalid
Sat Jun 20 19:05:14 UTC 2009
W. eWatson wrote:
> In some science working I'm doing, I need subsecond accuracy for
> timestamps. I was told the s/w in the Subject will do the trick.
> Maybe someone has used it before. I have little to go on, but
> installed it successfully yesterday--I think. I gave it the
> tick.usno.navy.mil NTP server name, and that finished the install.
> After a minute of looking at my clock, there was no change. It happened
> be maybe 30 sec off according to my atomic clock. What mechanism do
> I need to use to truly get it started? I don't think what I did showed
> it was
> adjusting my clock at all.
> I gave it one NTP server, as above, but probably need more. It allows
> up to 9. I'm on the west coast, California.
> There doesn't seem like much beginner support at their web site. None?
> See download page at <http://www.meinberg.de/english/sw/ntp.htm>
I'm sure you'll get more comprehensive replies, but as a guide with a good
Internet feed, figuring 4-5 servers, and using Windows 2000 or XP you
should get within about 100ms.
By making your own stratum-1 server with a $100 GPS puck such as the
Garmin GPS 18x LVC and a little soldering, you can get within 0.5
milliseconds using Windows - see the top two plots here:
You just need the puck to "see" about half the southern sky. With other
operating systems, results may be better.
At the command prompt, enter the command "ntpq -p" and post the results
here for people to help you. You may need to add ntpd.exe to your
programs allowed through your firewall.
More information about the questions