On Mon, Jun 13, 2011 at 1:37 PM, Per Molund <[email protected]> wrote: > Hello, > > I have an upcoming need for a GPS disciplined NTP server in a low cost > project. Checking price > on commercial units shows that these are out of reach so I have been looking > into the possibility > of building an NTP server.
Almost any PC hardware will work. If cost is an issue find a used computer. Even an old Pentium II is fast enough. Also NTP does not need it's own dedicated hardware, run NTP on any sever you happen to already have. NTp has very minimal hardware requirements. What you will need is a real hardware serial port, not a USB serial converter. So older computers really are good in that way. The ideal operating system is any recent Linux or even better BSD. But it can be made to work on most any OS. The GPS will cost more than the computer. You will need to give the antenna a clear view of the sky in all directions and then lead the cable inside to the GPS receiver. You should think about lightening protection and grounding. At some locations snow and ice on the antenna is a concern. If you need to have this work professionally done for you the cost will be more than a small computer. Next thing is to think about your requirements for reliability. If this is more than a hobby then you will likely need multiple NTP servers. How many more is an on-going debate. The answer depends if you have Internet connection and your requirement for accuracy and tolerance to down time. Even if you buy a commercial server you might think "How do I know if it is serving correct time?" This can be a hard problem or not depending on the details of your setup. The least expensive option is to simply run NTP on any computer you already have -- Chris Albertson Redondo Beach, California _______________________________________________ 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.
