To answer the original question, a Thunderbolt or similar GPS standard is MORE than capable of telling you if it is working properly. There is no reason to use more than one of them at a single location. The Trimble software will tell you how many nanoseconds the 1-PPS output is off, and how many parts per billion the 10-MHz output is off, compared to what GPS says they should be. And there are numerous diagnostic alarms that are monitored continuously.
It is a plug-and-forget device, except that you do want to set the saved location and environment (trees, fixed/mobile, etc.) properties when you install it. -- john, KE5FX > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Behalf Of Didier Juges > Sent: Tuesday, February 13, 2007 10:12 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Thunderbolt GPSDO > > > Well, some of us who have been on this list much longer than me can tell > you that when you only have one clock, it's pretty hard to tell if it's > working right, or how accurate it is. If you have two clocks, they > probably won't agree perfectly, and you have no way to tell which is > right, if any, so you are not much better off. > > So, if you have three clocks (more being better of course), you can > compare them 2 by 2 and draw some conclusions, with any luck, about > which one is the best, and how bad are the others. This will still not > tell you how good the best one is, but you are getting closer. > > You compare clocks using a statistical tool called Allan Deviation... > _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
