The VXCO quality hardly matters for an NTP server. As long as it does not gain out loose more then 1 uSecond per second. In other words one part per million is fine for NTP. The goal is not to produce a 10MHz GDPDO. Clients using this server over the Ethernet are happy to keep time ti 1 millisecond.
Most (almost all) NTP servers use a TTL can oscillator. On Wed, Dec 26, 2012 at 4:41 AM, M. Simon <msimon6...@yahoo.com> wrote: > You don't mention the quality of your VCXO. Do you have a part # or else > specs i.e. ppm vs temp, time, voltage, etc. > > > Nice pic btw. And that looks like an OSH Park "gold plated" board. I love > their service. > > > Simon > > ======================= > > > Message: 1 > Date: Tue, 25 Dec 2012 12:18:30 -0500 > From: Michael Tharp <g...@partiallystapled.com> > To: Discussion of precise time and frequency measurement > <time-nuts@febo.com> > Subject: [time-nuts] An embedded NTP server > Message-ID: <50d9dfe6.2050...@partiallystapled.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Hello and Merry Christmas, > > I made an embedded (S)NTP server. The software is still under > development and will eventually include a low-grade GPSDO but right now > even the simplistic algorithm is working quite well so I figured I'd share. > > http://www.eevblog.com/forum/oshw/%27laureline%27-embedded-gps-ntp-server/ > > This is a low-level microcontroller implementation, there is no OS nor > ntpd in the traditional sense. Just enough logic to keep time using the > incoming PPS and timestamps, and a tiny VCXO to discipline. It's no > Thunderbolt and there is no clock output but it should be fantastic at > NTP. Before too long I will have adapters for connecting to Oncore > GT+/UT+ (and maybe M12, haven't checked) as well as Trimble Resolution T > and Resolution SMT using a ribbon cable instead of the jumper wires. > > All open-source hardware and software. Pictures, details, and design > documents are in the eevblog thread. I'll let you all know if and when > I'm ready to sell them, for now I just wanted to show what I've got. > > -- m. tharp > > > > > > Engineering is the art of making what you want from what you can get at a > profit. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. -- Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.