Re: Recommendation on GPS time source for FreeBSD
Per olof Ljungmark p...@intersonic.se wrote: Does anyone have a recommendation on a good GPS receiver/board for use with NTP/FreeBSD to create a stratum 1 public time server? Anything with a PPS output. The Garmin GPS 18 LVC is probably the cheapest option. Preferably something above the Garmin puck level but not ridiculously expensive either... One of the u-blox evaluation kits (e.g. EVK-5T). http://www.u-blox.com/ -- Christian naddy Weisgerber na...@mips.inka.de ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: Re : Recommendation on GPS time source for FreeBSD
Alexandre L. axel...@ymail.com wrote: You can see here : http://www.meinberg.de/english/ Meinberg is one of those companies that don't even put price information on the web site: If you have to ask, you can't afford it. -- Christian naddy Weisgerber na...@mips.inka.de ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: Re : Recommendation on GPS time source for FreeBSD
With a clear view of the sky, pretty much any receiver but the lowest grade (havIng a 1pps output) should behave about the same. Ceramic patch antennas should have a decent ground plane. If the antenna is small (e.g. most puck antenna/receivers) put in on a 10in or 12in round metal disk (also blocks low-elevation reflected signals). Getting a lot better may involve considerable testing and characterization (i.e. $$'s), including site survey (line of sight obstacles, sources of multipath...), propagation/group delay in antenna/rf system, hardware involved in generating 1pps (slew rates...), sw tracking loop stability under various conditions (low signal level, addIng or dropping a satellite from the loop, ...). Dale Sent on the TELUS Mobility network with BlackBerry -Original Message- From: na...@mips.inka.de (Christian Weisgerber) Date: Sun, 31 Jan 2010 21:29:23 To: freebsd-questions@freebsd.org Subject: Re: Re : Recommendation on GPS time source for FreeBSD Alexandre L. axel...@ymail.com wrote: You can see here : http://www.meinberg.de/english/ Meinberg is one of those companies that don't even put price information on the web site: If you have to ask, you can't afford it. -- Christian naddy Weisgerber na...@mips.inka.de ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: Recommendation on GPS time source for FreeBSD
Christian Weisgerber wrote: Per olof Ljungmark p...@intersonic.se wrote: Does anyone have a recommendation on a good GPS receiver/board for use with NTP/FreeBSD to create a stratum 1 public time server? Anything with a PPS output. The Garmin GPS 18 LVC is probably the cheapest option. Preferably something above the Garmin puck level but not ridiculously expensive either... One of the u-blox evaluation kits (e.g. EVK-5T). http://www.u-blox.com/ There are many more factors involved than just getting a decent NMEA and PPS signal. We are in a building with obscured view of the sky (antenna must be on roof or at least up the wall), the server room is in the basement (long cable runs). Perhaps a Motorola ONCORE off e-bay + a proper antenna could be a way of getting started, I do realise that professional timekeeping equipment is expensive, just as any other high quality product made in small quantities. Thanks, ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re : Recommendation on GPS time source for FreeBSD
You can see here : http://www.meinberg.de/english/ I don't use their products (I don't know about the quality products), I just use their NTP package software for Windows. --- En date de : Sam 30.1.10, Per olof Ljungmark p...@intersonic.se a écrit : De: Per olof Ljungmark p...@intersonic.se Objet: Recommendation on GPS time source for FreeBSD À: freebsd-questions@freebsd.org Date: Samedi 30 Janvier 2010, 9h51 Hi all, Does anyone have a recommendation on a good GPS receiver/board for use with NTP/FreeBSD to create a stratum 1 public time server? Preferably something above the Garmin puck level but not ridiculously expensive either... Thanks for any input, -- per ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: Recommendation on GPS time source for FreeBSD
On Jan 30, 2010, at 3:51 AM, Per olof Ljungmark wrote: Hi all, Does anyone have a recommendation on a good GPS receiver/board for use with NTP/FreeBSD to create a stratum 1 public time server? Preferably something above the Garmin puck level but not ridiculously expensive either... Why would you want something more than the Garmin puck? I have a couple of instrumentation grade GPS's at work but their primary justification is to generate IRIG time to sync a multitude of instruments which expect a time signal in IRIG format. -- David Kelly N4HHE, dke...@hiwaay.net Whom computers would destroy, they must first drive mad. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
