<[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Hey all, > > I am looking at the possibility of using a GPS receiver for NTP time sync > either via the nmea refclock driver or gpsd, just a little home project. > From my googling, I've read that the only way to get decent results is to go > with an rs232 sync and stay clear of usb or bluetooth. Looking at the > mainstream gps sites, I've found the Globalsat br-355 unit and I'm wondering > whether this is suitable for NTP sync and what kind of accuracy I should > expect. > > http://www.buygpsnow.com/globalsat-br-355-water-proof-serial-gps-receiver-si rf-star-iii-br355-v3-1-1-free-arkon-mount-432.aspx > > The device seems to use a ps2 cable which converts via a y-cable into a db9 > serial connection and gets power from the PS2. What I can't seem to find in > the specs or on the globalsat site is whether the db9 connection provides a > PPS output. If not, are there any PPS capable receivers out there that > don't require electronics knowhow (soldering etc.)? That's all I've found > so far. > > Tia, > Shane
What OS and what kind of receiver? I've used a handheld on my Windows desktop with, um, amusing results. I used PPS, but the NMEA app couldn't tell whether the pulse belonged to the previous second or the upcoming second, with the result that I was always one second slow. Then, of course, there's Windows' granularity issues, which assured that even with PPS properly configured I wouldn't have been able to get much below 20 ms. With a real OS and a dedicated receiver (save the Magellan for hiking), you ought to get better results than I did--sub-millisecond, I would think. Brian _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
