03/08/2017 14:50 I use an NTP client to set my Windows 7 64 bit PC time for digital mode amateur radio activities, but I was wondering if my Trimble Thunderbolt and Lady Heather can do the same job? If it can, how do I do it please, and can the PC show GMT and not UTC, and finally does the date glitch affect this? Lady Heather communicates with the GPS via a true serial port. Thanks! -- Best Regards, Chris Wilson. 2E0ILY mailto: chris@chriswilson.tv

This idea keeps coming up. "Jamming" the time from a GPS into a computer is NEVER the best idea. When you "jam" the time the PC internal clock moves in jerks and jumps where it will move forward and even backward. The only way that works well is to discipline the PC's clock using the same method you'd use to discipline the crystal inside A GPSDO. You compare the phase between the GPS and the local PC clock then adjust the RATE of the PC clock to keep the peas in sync. That is what NTP does. I say all of the above because this is a "timeouts" list. If you only care that the PC clock by "close enough" that the time printed on the screen matches your wristwatch then a 50 millisecond error is acceptable as that is about the limit of human perception. But it you are a "nut" and want each millisecond of time to be reasonably equal, that means with "tick" of the PC's clock to advance in time about the same amount then you can't "jam" the PC's clock from GPS. You will need to adjust the PC clock's RATE not the PC clock's PHASE. On Thu, Aug 3, 2017 at 6:54 AM, Chris Wilson <chris@chriswilson.tv> wrote: > > > 03/08/2017 14:50 > > I use an NTP client to set my Windows 7 64 bit PC time for digital > mode amateur radio activities, but I was wondering if my Trimble > Thunderbolt and Lady Heather can do the same job? If it can, how do I > do it please, and can the PC show GMT and not UTC, and finally does > the date glitch affect this? Lady Heather communicates with the GPS > via a true serial port. Thanks! > > -- > Best Regards, > Chris Wilson. 2E0ILY > mailto: chris@chriswilson.tv > > _______________________________________________ > 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

   Best Regards,
               Chris Wilson. 2E0ILY

I use an NTP client to set my Windows 7 64 bit PC time for digital mode amateur radio activities, but I was wondering if my Trimble Thunderbolt and Lady Heather can do the same job? If it can, how do I do it please, and can the PC show GMT and not UTC, and finally does the date glitch affect this? Lady Heather communicates with the GPS via a true serial port. Thanks! Best Regards, Chris Wilson. 2E0ILY ============================================= Chris, If you have a PPS source you can use that directly with your Windows-7 PC. I have some notes here: http://www.satsignal.eu/ntp/Sure-GPS.htm Windows works internally in UTC, just choose your time zone from the Control Panel. I'm guessing that you mean UK local time, as GMT and UTC are the same (at least as far as wall-clock time is concerned). 73, David GM8ARV -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-taylor@blueyonder.co.uk Twitter: @gm8arv

   Best Regards,
               Chris Wilson. 2E0ILY

Could Lady Heather provide an NTP server so a local NTP client could access the GPS time ? Or is that an overcomplicated way to do it? On 3 Aug 2017 20:19, "David J Taylor via time-nuts" <time-nuts@febo.com> wrote: > I use an NTP client to set my Windows 7 64 bit PC time for digital > mode amateur radio activities, but I was wondering if my Trimble > Thunderbolt and Lady Heather can do the same job? If it can, how do I > do it please, and can the PC show GMT and not UTC, and finally does > the date glitch affect this? Lady Heather communicates with the GPS > via a true serial port. Thanks! > > Best Regards, > Chris Wilson. 2E0ILY > ============================================= > > Chris, > > If you have a PPS source you can use that directly with your Windows-7 PC. > I have some notes here: > > http://www.satsignal.eu/ntp/Sure-GPS.htm > > Windows works internally in UTC, just choose your time zone from the > Control Panel. I'm guessing that you mean UK local time, as GMT and UTC > are the same (at least as far as wall-clock time is concerned). > > 73, > David GM8ARV > -- > SatSignal Software - Quality software written to your requirements > Web: http://www.satsignal.eu > Email: david-taylor@blueyonder.co.uk > Twitter: @gm8arv > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/m > ailman/listinfo/time-nuts > and follow the instructions there. >

Adrian Godwin wrote: > Could Lady Heather provide an NTP server so a local NTP client could access > the GPS time ? Or is that an overcomplicated way to do it? If LH can adjust the system time (I don't know if it can) then you could in addition install ntpd and configure the "local clock" 127.127.1.0 as the only reference time source. Then ntpd does not adjust the system time but makes the adjusted system time available to NTP clients on the network. Martin