Re: [time-nuts] Leap Second video
Good job Arthur and it makes sense since the wwvb clock simply checks every 24 hours it would continue on the old time and GPS updates instantly. Nicely done. Regards Paul WB8TSL On Wed, Jul 1, 2015 at 12:34 AM, Arthur Dent golgarfrinc...@gmail.com wrote: Here is a short video of the leap second compared to a regular clock. http://youtu.be/725ECUOXqeY -Arthur ___ 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. ___ 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.
Re: [time-nuts] Reeeely long term HP 5065A drift rate (13 year!)
On 6/30/2015 10:21 AM, cdel...@juno.com wrote: Yes, same workbench and location! How about some of the 5065A owners helping out in a bigger sample? What I thought is that say on July the 4th a few owners measure their frequency offset to say at least 5X10-12th and then without changing the C-field for a year we could repeat the measurement next year and see what kind of results we get. Corby, by some quirk of fate I have a 5065A here that has been operating continuously (apart from the odd power outage of longer than the batteries could supply) since 2002. My problem is that I'm not sure how to get to the degree of accuracy that you ask. I set it originally using a really old method, feeding 5MHz from it and another input from a GPS standard into a DB mixer and plotting the output on a pen recorder, getting down to better than one cycle error per 24 hours. A quick check today on a 2465B 'scope shows an absolutely static trace at the highest timebase speed. What measurement method would you recommend, absent a working Caesium standard and a Timepod? I have a 5370B somewhere, but nothing more modern. Dan ___ 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.
Re: [time-nuts] End Of The World
Le 1 juil. 2015 à 09:02, Hal Murray hmur...@megapathdsl.net a écrit : michael.c...@sfr.fr said: Lady Heather just went told me 23:59:59 , 00:00:00 and stayed there for 2 secs, No 23:59:60 :-( What sort of device was it looking at? a T-Bolt. Firmware 3.0 GPS 10.2 .Mfg. 2002. Leap status was Leap Pending! I have it on video. -- These are my opinions. I hate spam. ___ 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. Ceux qui sont prêts à abandonner une liberté essentielle pour obtenir une petite et provisoire sécurité, ne méritent ni liberté ni sécurité. Benjimin Franklin ___ 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.
Re: [time-nuts] [Bulk] Leap second results: LH screenshot
Interestingly, the time is 23:59:60 but the UTC ofs is still 16. I guess it increments to 17 at the end of that operation, i.e., at 00:00:00. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Scott Newell Sent: Tuesday, June 30, 2015 7:29 PM To: time-nuts@febo.com Subject: [Bulk] [time-nuts] Leap second results: LH screenshot The /nd=1sr command made this capture a piece of cake: http://www.n5tnl.com/time/leap_2015/tbolt_leap.gif ___ 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. ___ 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.
Re: [time-nuts] End Of The World
My NTP server did a double 59 on the terminal. for anybody who is interested I captured the event : https://youtu.be/OpNci29CI7E I did measure an odd behaviour on leapsecond day from time-a.nist.gov NTP server usually it runs about 8 mS behind my local PPS but all the sudden went to +22 mS for most of the the UTC day, see: https://flic.kr/p/vnZGaU a few minutes after 00:00 it returned to the usual offset https://flic.kr/p/vrPsAR 73 Frits W1FVB On 01/07/2015, Martin Burnicki martin.burni...@burnicki.net wrote: Bob Camp schrieb: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? From a NVD8C-CSM v3.1 module in Glonass-only mode: $GPZDA,235958.00,30,06,2015,00,00*65 $GPGGA,235959.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*53 $GPRMC,235959.00,A,5158.9396,N,00913.5513,E,00.00,144.5,300615,,,A*5F $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,46,69,74,335,41,70,26,270,49,77,17,018,35*61 $GLGSV,3,2,10,78,34,075,43,79,18,125,40,83,06,190,38,84,43,230,42*6F $GLGSV,3,3,10,85,42,304,45,86,07,344,38*68 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GPZDA,235959.00,30,06,2015,00,00*64 $GPGGA,00.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*52 $GPRMC,00.00,A,5158.9396,N,00913.5513,E,00.00,144.5,010715,,,A*5D $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,46,69,74,335,40,70,26,270,49,77,17,018,36*63 $GLGSV,3,2,10,78,34,075,43,79,18,125,41,83,06,190,39,84,43,230,42*6F $GLGSV,3,3,10,85,42,304,46,86,07,344,37*64 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GLGBS,00.00,2.0,1.8,5.2*51 $GPZDA,00.00,01,07,2015,00,00*66 $GPGGA,01.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*53 $GPRMC,01.00,A,5158.9396,N,00913.5513,E,00.00,144.5,010715,,,A*5C $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,44,69,74,335,39,70,26,270,47,77,17,018,34*63 $GLGSV,3,2,10,78,34,075,42,79,18,125,39,83,06,190,37,84,43,230,41*6C $GLGSV,3,3,10,85,42,304,44,86,07,344,36*67 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GPZDA,01.00,01,07,2015,00,00*67 RestartKÕÎ$GPGGA,00.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5E $GPRMC,00.00,V,.,N,0.,E,00.00,000.0N*46 $GPGSV,1,1,00*79 $GLGSV,1,1,00*65 $GPGSA,A,1,,,*1E $PORZD,V,999.9*2B $GPGBS,00.00,,,*6F $ALVER,NVS,CSM23,0207*72 $POTST,ID,0268501855,ANT,1,RFG,0,RFR,0*3E $GPGGA,01.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5F $GPRMC,01.00,V,.,N,0.,E,00.00,000.0N*47 $GPGSV,1,1,00*79 $GLGSV,1,1,00*65 $GPGSA,A,1,,,*1E $PORZD,V,999.9*2B $GPZDA,01.0000,00*67 $GPGGA,02.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5C $GPRMC,02.00,V,.,N,0.,E,00.00,000.0N*44 The module restarted itself when the leap second occurred. Martin ___ 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. -- vbradio.wordpress.com ___ 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.
Re: [time-nuts] End Of The World
michael.c...@sfr.fr said: Lady Heather just went told me 23:59:59 , 00:00:00 and stayed there for 2 secs, No 23:59:60 :-( What sort of device was it looking at? -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] End Of The World
At home I recorded the following seconds: Tunderbolt GPSDO 58 59 60 00 01 02 Meinberg LANTIME M200 58 59 59 00 01 02 hopf DCF 7001 58 59 60 01 02 03 Conrad DCF Time Terminal 58 59 00 01 02 03 The (old 1999) DCF hopf clock in particular was a strange one. It announced a leap event an hour before. Then it went from second 59, 60 to 01, so it was still a second ahead! After 8 minutes it counted the 01 second two times. From then on it showed the correct time. Local time was 02:00 hours, so i've missed some sleep. This morning at work we've found some 'link errors' in application logs at exactly 23:59:59. NTP clients were out of sync for some time. But no big problems reported yet. Bob Camp schreef op 2015-07-01 03:03: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ 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. ___ 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.
Re: [time-nuts] End Of The World
time-nuts@febo.com said: As expected, on the leap second the display on the 8183 showed 6:59:60 (the 8183-A showed 23:59:60), but the TV400 displayed 7:00:00 at that moment. The TV400 remained one second ahead until it displayed 7:00:03 for a two-second period, then from 7:00:04 forward it was properly synced. My guess is that there is a CPU in the TV400 that is smart enough to filter out noise but not smart enough to know about leap seconds. It considers 23:59:60 to be noise and rejects it. The following data gets rejected because it doesn't match the predicted time. After a few seconds of data that is self-consistent, it switches to the new time. -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] End Of The World
Bob Camp schrieb: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? From a NVD8C-CSM v3.1 module in Glonass-only mode: $GPZDA,235958.00,30,06,2015,00,00*65 $GPGGA,235959.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*53 $GPRMC,235959.00,A,5158.9396,N,00913.5513,E,00.00,144.5,300615,,,A*5F $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,46,69,74,335,41,70,26,270,49,77,17,018,35*61 $GLGSV,3,2,10,78,34,075,43,79,18,125,40,83,06,190,38,84,43,230,42*6F $GLGSV,3,3,10,85,42,304,45,86,07,344,38*68 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GPZDA,235959.00,30,06,2015,00,00*64 $GPGGA,00.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*52 $GPRMC,00.00,A,5158.9396,N,00913.5513,E,00.00,144.5,010715,,,A*5D $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,46,69,74,335,40,70,26,270,49,77,17,018,36*63 $GLGSV,3,2,10,78,34,075,43,79,18,125,41,83,06,190,39,84,43,230,42*6F $GLGSV,3,3,10,85,42,304,46,86,07,344,37*64 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GLGBS,00.00,2.0,1.8,5.2*51 $GPZDA,00.00,01,07,2015,00,00*66 $GPGGA,01.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*53 $GPRMC,01.00,A,5158.9396,N,00913.5513,E,00.00,144.5,010715,,,A*5C $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,44,69,74,335,39,70,26,270,47,77,17,018,34*63 $GLGSV,3,2,10,78,34,075,42,79,18,125,39,83,06,190,37,84,43,230,41*6C $GLGSV,3,3,10,85,42,304,44,86,07,344,36*67 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GPZDA,01.00,01,07,2015,00,00*67 RestartKÕÎ$GPGGA,00.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5E $GPRMC,00.00,V,.,N,0.,E,00.00,000.0N*46 $GPGSV,1,1,00*79 $GLGSV,1,1,00*65 $GPGSA,A,1,,,*1E $PORZD,V,999.9*2B $GPGBS,00.00,,,*6F $ALVER,NVS,CSM23,0207*72 $POTST,ID,0268501855,ANT,1,RFG,0,RFR,0*3E $GPGGA,01.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5F $GPRMC,01.00,V,.,N,0.,E,00.00,000.0N*47 $GPGSV,1,1,00*79 $GLGSV,1,1,00*65 $GPGSA,A,1,,,*1E $PORZD,V,999.9*2B $GPZDA,01.0000,00*67 $GPGGA,02.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5C $GPRMC,02.00,V,.,N,0.,E,00.00,000.0N*44 The module restarted itself when the leap second occurred. Martin ___ 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.
Re: [time-nuts] Help with my ADEV measurement setup
Oddly enough I do have a PPS output from the TCXO I was measuring. It's on a little board I made and there is a PicDiv right on it. I'll have to play around with that. I did notice the aliasing issue trying to measure a 12MHz crystal. It appeared to have incredible stability and accuracy for a plain old XO... Also it has a frequency offset of over 1kHz, and I noticed that I had to manually type in the correct initial frequency during setup to have meaningful data in the frequency difference view. i.e, 12001053 instead of 12E6. But of course with a marginally stably oscillator, that poses a problem. How long do I wait to find a mean frequency to type in...? It makes total sense why this is so in TI mode, but still it's one more thing to deal with. I think I'll stick with frequency mode for most things. Many of the oscillators I want to measure are right around 10^-8 or 10^-9, and I'd hate to constantly be fighting the noise floor of the instrument. I'll treat the data from frequency mode as relative and that should get me what I need. At least until I own a better instrument. Thanks Dan On Tue, Jun 30, 2015 at 10:49 PM, John Miles j...@miles.io wrote: Yep, it will ignore any non-numeric data like us suffixes. It will always interpret incoming data as seconds, so the 1E-6 scale factor is appropriate if the counter is returning microseconds. I'll tweak the mouseover help text for the scale factor field to clarify that. I think you're basically getting valid data. The 53131A's one-shot resolution is 0.5 ns, and you're seeing about 2E-9 residual ADEV at t=1s. It's in the right ballpark, anyway... e.g., on a 20-ps HP 5370, the residual ADEV at t=1s will usually be in the neighborhood of 30-60 ps. I would, however, be worried about aliasing with a TCXO. If its frequency is more than 5E-8 off -- meaning it drifts more than 50 nanoseconds per second with 10 MHz at the STOP jack -- its error will end up underrepresented in the measurement. In this case your oscillator is drifting quite a bit (as expected) -- look at the 'w' view of the original phase compared to the unwrapped 'p' phase. You could try putting 1pps on both the START and STOP jacks but that'll require more futzing with scale factors, 1pps dividers and the like, and may leave you more vulnerable to trigger uncertainty from various causes. For measurement of a TCXO, I'd stick with frequency mode. The ADEV plots won't be 100% kosher but they'll be fine for relative comparisons with other plots from the same measurement setup. -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Watson Sent: Tuesday, June 30, 2015 5:05 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Help with my ADEV measurement setup I tried both the PPS and the 10MHz signal on channel 1, with the 10MHz DUT on channel 2. Tom emailed me and it turns out the software was not detecting the units correctly from the serial string. (What are 6 powers of ten between friends, right? :) ) Likely a settings mistake on my part, I sent him a screen cap to see what's up. None the less, I manually enter the time units and was able to plot some data. I attached a new screen cap. How does this look? Thanks Dan On Tue, Jun 30, 2015 at 5:36 PM, Bob Camp kb...@n1k.org wrote: Hi Are you using a PPS as the “start” and the 10 MHz as the “stop” or comparing two PPS signals? Bob On Jun 30, 2015, at 2:47 PM, Dan Watson watsondani...@gmail.com wrote: Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup: - 53131A with the OCXO option. Calibrated against a T-bolt. I also did the TI Quik cal and it passed - I'm using RS-232 out with a null modem cable into a Serial-USB converter - Software is TimeLab in talk-only mode. 53131A check box is checked. - The counter is in TI mode, with a T-bolt on Channel 1 and DUT on Channel 2 - A delay of 1 second is set on the counter. TimeLab seems to accurately detect this interval I started measuring various devices, and could never seem to get better than around 1x10^-6. Even my Rb was showing a 1 second ADEV of 10^-6. Finally I put the T-bolt on channel 1 with common mode on to both channels, and it still measures around 10^-6. A picture of that is attached. Surely this can't be right. I tried frequency mode and it gives ADEVs of 10^-12 on the Rb and T-bolt, as expected. I understand the issues with filtering that the 53131A does internally on this mode, but at least it shows my setup is working to some degree. It's TI mode that seems to be wonky. I'm probably doing something really stupid. Thanks for any help you all can suggest. Regards, Dan W
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
On 01/07/2015 16:23, Tom Van Baak wrote: 3) Adafruit Ultimate GPS Breakout http://www.adafruit.com/products/746 This GPS receiver appeared to mess up the 2015 leap second, with a double 5959 and possible receiver reset: (I also had serial communications issues with this board today) If someone else has data from this model receiver, please let me know. I have the same board and got a double 59, but no reset: $GPGGA,235958.000,X,N,X,W,2,9,0.90,98.5,M,48.7,M,,*77 $GPRMC,235958.000,A,X,N,X,W,0.01,220.71,300615,,,D*7A $GPGGA,235959.000,X,N,X,W,2,9,0.90,98.5,M,48.7,M,,*76 $GPRMC,235959.000,A,X,N,X,W,0.01,220.71,300615,,,D*7B $GPGGA,235959.000,X,N,X,W,2,9,0.90,98.5,M,48.7,M,,*76 $GPRMC,235959.000,A,X,N,X,W,0.02,220.71,300615,,,D*78 $GPGGA,00.000,X,N,X,W,2,9,0.90,98.5,M,48.7,M,,*77 $GPRMC,00.000,A,X,N,X,W,0.03,220.71,010715,,,D*7B $GPGGA,01.000,X,N,X,W,2,9,0.90,98.5,M,48.7,M,,*76 $GPRMC,01.000,A,X,N,X,W,0.01,220.71,010715,,,D*78 My linux boxes also did a double 59: Wed Jul 1 00:59:58 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 01:00:00 BST 2015 Wed Jul 1 01:00:01 BST 2015 Cheers Simon ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
I am missing something here. How does one use a 1 PPS signal? I see how I can use a 1 MHz or 10 MHz for a time standard but the 1 PPS usage eludes me. Unless the pulse is extremely sharp, a minor uncertainty in the shape or amplitude will have profound effects on the timing. I use an HP 5328A with the OCXO and wonder how I can improve its accuracy. Bob On Wednesday, July 1, 2015 10:01 AM, Tom Van Baak t...@leapsecond.com wrote: I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). 1) Parallax PAM-7Q GPS Module https://www.parallax.com/product/28509 When I powered up this board, I see: $GPTXT,01,01,02,u-blox ag - www.u-blox.com*50 $GPTXT,01,01,02,HW UBX-G70xx 0007 EFFFo*1B $GPTXT,01,01,02,ROM CORE 1.00 (59842) Jun 27 2012 17:43:52*59 $GPTXT,01,01,02,PROTVER 14.00*1E $GPTXT,01,01,02,ANTSUPERV=AC SD PDoS SR*20 $GPTXT,01,01,02,ANTSTATUS=DONTKNOW*33 $GPTXT,01,01,02,LLC -FFED---FF79*21 And it appeared to handle the 2015 leap second perfectly: $GPRMC,235959.00,A,4733.25270,N,12208.36733,W,0.329,,300615,,,D*65 $GPGGA,235959.00,4733.25270,N,12208.36733,W,2,09,1.01,308.9,M,-18.8,M,,*61 $GPGLL,4733.25270,N,12208.36733,W,235959.00,A,D*75 $GPRMC,235960.00,A,4733.25285,N,12208.36731,W,0.181,,300615,,,D*67 $GPGGA,235960.00,4733.25285,N,12208.36731,W,2,09,1.01,308.5,M,-18.8,M,,*6F $GPGLL,4733.25285,N,12208.36731,W,235960.00,A,D*77 $GPRMC,00.00,A,4733.25301,N,12208.36743,W,0.312,,010715,,,D*6F $GPGGA,00.00,4733.25301,N,12208.36743,W,2,09,1.01,308.0,M,-18.8,M,,*69 $GPGLL,4733.25301,N,12208.36743,W,00.00,A,D*74 $GPRMC,01.00,A,4733.25317,N,12208.36749,W,0.166,,010715,,,D*62 $GPGGA,01.00,4733.25317,N,12208.36749,W,2,09,1.01,307.6,M,-18.8,M,,*6C $GPGLL,4733.25317,N,12208.36749,W,01.00,A,D*78 2) Reyax as found by multiple sellers on eBay http://www.reyax.com/httpdocs/index.files/GPS_Module.htm When I powered up this board, I see: $GNTXT,01,01,02,u-blox AG - www.u-blox.com*4E $GNTXT,01,01,02,HW UBX-M80xx 0008 *43 $GNTXT,01,01,02,EXT CORE 2.01 (75350) Oct 29 2013 16:15:41*5C $GNTXT,01,01,02,ROM BASE 2.01 (75331) Oct 29 2013 13:28:17*44 $GNTXT,01,01,02,MOD NEO-M8N-0*7A $GNTXT,01,01,02,PROTVER 15.00*01 $GNTXT,01,01,02,GNSS OTP: GPS GLO, SEL: GPS GLO*67 $GNTXT,01,01,02,ANTSUPERV=AC SD PDoS SR*3E $GNTXT,01,01,02,ANTSTATUS=DONTKNOW*2D $GNTXT,01,01,02,FIS 0xEF4015 (73171) found*20 $GNTXT,01,01,02,LLC -FFED---FF69*3E $GNTXT,01,01,02,RF0 dev ok*04 It also appeared to handle the 2015 leap second perfectly: $GNRMC,235959.00,A,4733.25534,N,12208.36945,W,0.052,,300615,,,D*7C $GNGGA,235959.00,4733.25534,N,12208.36945,W,2,12,1.06,315.5,M,-18.8,M,,*7A $GNGLL,4733.25534,N,12208.36945,W,235959.00,A,D*63 $GNRMC,235960.00,A,4733.25539,N,12208.36940,W,0.076,,300615,,,D*78 $GNGGA,235960.00,4733.25539,N,12208.36940,W,2,08,1.23,315.4,M,-18.8,M,,*75 $GNGLL,4733.25539,N,12208.36940,W,235960.00,A,D*61 $GNRMC,00.00,A,4733.25545,N,12208.36936,W,0.011,,010715,,,D*7B $GNGGA,00.00,4733.25545,N,12208.36936,W,2,06,1.59,315.4,M,-18.8,M,,*77 $GNGLL,4733.25545,N,12208.36936,W,00.00,A,D*60 $GNRMC,01.00,A,4733.25546,N,12208.36933,W,0.181,,010715,,,D*74 $GNGGA,01.00,4733.25546,N,12208.36933,W,2,06,1.59,315.3,M,-18.8,M,,*77 $GNGLL,4733.25546,N,12208.36933,W,01.00,A,D*67 3) Adafruit Ultimate GPS Breakout http://www.adafruit.com/products/746 When I powered up this board I see: $PGACK,103*40 $PGACK,105*46 $PMTK011,MTKGRS*08 $PMTK010,001*2E $PMTK010.002*2D This GPS receiver appeared to mess up the 2015 leap second, with a double 5959 and possible receiver reset: (I also had serial communications issues with this board today) $GPGGA,235958.000,t733.2401,N,12208.7780,W,2,7,1.17,257.6,M,-17.3,S000,*62 GPRMC,235958.000,A,4723.2401,N12208.3780,W,0.4x,48.15,300615,,,D*4D $GPGGA,235959.000,4733.2401,N,52208.3778,W,2,7,1.17,257.6,M,-17.3,M,,*64 $GQRMC,235959.000,A,47;3.2401,N,12208.3778,W,0.47,48.15,300615,,,D*44 $GPGGA,235959.000,4733.2402,N,12208.3777,W,2,7,1.17,257.6,M,-17.3,M,,*68- $GPRMC,235959.00,A,4733.2402,N,12208.3777W,0.46,48.17,300615,,,D*49 $GPRMC,0,A,4733.2403,N,12208.3775,W,0.38,4815,010715,,,D*41 $GPGGA,01.000,4733.2403,N,12208.3773,W,2,7,1.17,257.6,],-17.3,M,,*6D $GPRMC,01.000,A,4733.2403,N,12208.3773,W,0.22,48.15,010715,,,D*4D If someone else has data from this model receiver, please let me know. Thanks, /tvb www.LeapSecond.com ___ 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. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
subscripti...@burble.com said: My linux boxes also did a double 59: Wed Jul 1 00:59:58 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 01:00:00 BST 2015 Wed Jul 1 01:00:01 BST 2015 That's to be expected (unless you have fancy software). Internally, Linux (and most other modern OSes) use UTC. The API doesn't include the TAI offset. There is no way to talk about the extra second. The same problem happens with the switch to summer time. You need the time-zone to tell if the time within the magic extra hour is summer time or winter time. Without the zone, you have to pick one and then there is no way to talk about the other one. To insert the extra second, Linux just sets the time back 1 second, the same way you set your clocks and watches back in the fall. -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] End Of The World
t...@leapsecond.com said: Am I reading this right -- those GPS receivers applied the leap second 16 seconds before they were supposed to, resulting in a double 23:59:44 instead of 23:59:59 and 23:59:60? So not only did they use GPS instead of UTC but the opted for the double second instead of a valid leap second. That's my reading. 57203 86383.752 $GPRMC,235943.000,A,3726.0874,N,12212.2628,W,1.71,186.96,300615,,*1A 57203 86384.750 $GPRMC,235944.000,A,3726.0866,N,12212.2630,W,1.33,180.14,300615,,*1D 57203 86385.752 $GPRMC,235944.000,A,3726.0858,N,12212.2631,W,1.10,178.01,300615,,*13 57203 86386.751 $GPRMC,235945.000,A,3726.0850,N,12212.2632,W,1.18,179.98,300615,,*10 -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
Hi Bob, For precise timing we use the 1PPS output of a GPS receiver. And yes, it is typically extremely sharp and precise. If you want 1 MHz or 10 MHz then you need all the complication of a disciplined oscillator. But the timing itself comes from the receiver's 1PPS pulse. Even without accurate survey or position hold mode or sawtooth correction, a plain, cheap GPS/1PPS receiver makes a superb long-term accurate time source. In this example of a cheap GPS 1PPS (http://www.leapsecond.com/pages/MG1613S/), the risetime was 2 ns. The rms jitter was 22 ns. This is more than enough for a 5328A to fully calibrate any OCXO. Just use the 1PPS and a 1 or 10 MHz OCXO as the start and stop channels in TI mode and record the gradual drift of phase between them. Programs like TimeLab will handle the occasional 1 us or 100 ns phase wrap. Use something like 1 VDC trigger for the 1PPS and 0 VAC for the OCXO trigger. A rule-of-thumb is that if it drifts 1 us over a day the frequency offset is 1e-11 /tvb - Original Message - From: Bob Albert To: Tom Van Baak ; Discussion of precise time and frequency measurement ; Discussion of precise time and frequency measurement Sent: Wednesday, July 01, 2015 10:55 AM Subject: Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers I am missing something here. How does one use a 1 PPS signal? I see how I can use a 1 MHz or 10 MHz for a time standard but the 1 PPS usage eludes me. Unless the pulse is extremely sharp, a minor uncertainty in the shape or amplitude will have profound effects on the timing. I use an HP 5328A with the OCXO and wonder how I can improve its accuracy. Bob On Wednesday, July 1, 2015 10:01 AM, Tom Van Baak t...@leapsecond.com wrote: I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). ... ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
Hi Bob, For precise timing we use the 1PPS output of a GPS receiver. And yes, it is typically extremely sharp and precise. If you want 1 MHz or 10 MHz then you need all the complication of a disciplined oscillator. But the timing itself comes from the receiver's 1PPS pulse. Even without accurate survey or position hold mode or sawtooth correction, a plain, cheap GPS/1PPS receiver makes a superb long-term accurate time source. In this example of a cheap GPS 1PPS (http://www.leapsecond.com/pages/MG1613S/), the risetime was 2 ns. The rms jitter was 22 ns. This is more than enough for a 5328A to fully calibrate any OCXO. Just use the 1PPS and a 1 or 10 MHz OCXO as the start and stop channels in TI mode and record the gradual drift of phase between them. Programs like TimeLab will handle the occasional 1 us or 100 ns phase wrap. Use something like 1 VDC trigger for the 1PPS and 0 VAC for the OCXO trigger. A rule-of-thumb is that if it drifts 1 us over a day the frequency offset is 1e-11 /tvb - Original Message - From: Bob Albert To: Tom Van Baak ; Discussion of precise time and frequency measurement ; Discussion of precise time and frequency measurement Sent: Wednesday, July 01, 2015 10:55 AM Subject: Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers I am missing something here. How does one use a 1 PPS signal? I see how I can use a 1 MHz or 10 MHz for a time standard but the 1 PPS usage eludes me. Unless the pulse is extremely sharp, a minor uncertainty in the shape or amplitude will have profound effects on the timing. I use an HP 5328A with the OCXO and wonder how I can improve its accuracy. Bob On Wednesday, July 1, 2015 10:01 AM, Tom Van Baak t...@leapsecond.com wrote: I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). ___ 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.
Re: [time-nuts] End Of The World
Hi Hal, Am I reading this right -- those GPS receivers applied the leap second 16 seconds before they were supposed to, resulting in a double 23:59:44 instead of 23:59:59 and 23:59:60? So not only did they use GPS instead of UTC but the opted for the double second instead of a valid leap second. /tvb - Original Message - From: Hal Murray hmur...@megapathdsl.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: hmur...@megapathdsl.net Sent: Tuesday, June 30, 2015 8:38 PM Subject: Re: [time-nuts] End Of The World Any observations of anomalous behavior yet? From a BU-353: 57203 86380.750 $GPRMC,235940.000,A,3726.0893,N,12212.2627,W,0.52,64.49,300615,,*20 57203 86381.748 $GPRMC,235941.000,A,3726.0889,N,12212.2627,W,0.45,78.54,300615,,*2D 57203 86383.138 $GPRMC,235942.000,A,3726.0883,N,12212.2627,W,0.82,157.71,300615,,*14 57203 86383.752 $GPRMC,235943.000,A,3726.0874,N,12212.2628,W,1.71,186.96,300615,,*1A 57203 86384.750 $GPRMC,235944.000,A,3726.0866,N,12212.2630,W,1.33,180.14,300615,,*1D 57203 86385.752 $GPRMC,235944.000,A,3726.0858,N,12212.2631,W,1.10,178.01,300615,,*13 57203 86386.751 $GPRMC,235945.000,A,3726.0850,N,12212.2632,W,1.18,179.98,300615,,*10 57203 86388.136 $GPRMC,235946.000,A,3726.0842,N,12212.2630,W,1.67,146.83,300615,,*1C 57203 86388.752 $GPRMC,235947.000,A,3726.0836,N,12212.2627,W,1.15,129.24,300615,,*19 From a MR-350P 57203 86382.186 $GPRMC,235941.000,A,3726.0808,N,12212.2649,W,0.27,67.38,300615,,*2C 57203 86382.799 $GPRMC,235942.000,A,3726.0807,N,12212.2652,W,0.37,210.08,300615,,*1A 57203 86383.805 $GPRMC,235943.000,A,3726.0811,N,12212.2647,W,0.48,95.98,300615,,*26 57203 86384.807 $GPRMC,235944.000,A,3726.0812,N,12212.2647,W,0.17,210.63,300615,,*13 57203 86385.806 $GPRMC,235944.000,A,3726.0810,N,12212.2648,W,0.29,145.10,300615,,*14 57203 86387.188 $GPRMC,235945.000,A,3726.0809,N,12212.2647,W,0.39,174.68,300615,,*1E 57203 86387.807 $GPRMC,235946.000,A,3726.0806,N,12212.2647,W,0.54,173.43,300615,,*17 ___ 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.
Re: [time-nuts] End Of The World
Hi On Jul 1, 2015, at 6:25 AM, Martin Burnicki martin.burni...@burnicki.net wrote: Bob Camp schrieb: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? From a NVD8C-CSM v3.1 module in Glonass-only mode: $GPZDA,235958.00,30,06,2015,00,00*65 $GPGGA,235959.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*53 $GPRMC,235959.00,A,5158.9396,N,00913.5513,E,00.00,144.5,300615,,,A*5F $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,46,69,74,335,41,70,26,270,49,77,17,018,35*61 $GLGSV,3,2,10,78,34,075,43,79,18,125,40,83,06,190,38,84,43,230,42*6F $GLGSV,3,3,10,85,42,304,45,86,07,344,38*68 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GPZDA,235959.00,30,06,2015,00,00*64 $GPGGA,00.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*52 $GPRMC,00.00,A,5158.9396,N,00913.5513,E,00.00,144.5,010715,,,A*5D $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,46,69,74,335,40,70,26,270,49,77,17,018,36*63 $GLGSV,3,2,10,78,34,075,43,79,18,125,41,83,06,190,39,84,43,230,42*6F $GLGSV,3,3,10,85,42,304,46,86,07,344,37*64 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GLGBS,00.00,2.0,1.8,5.2*51 $GPZDA,00.00,01,07,2015,00,00*66 $GPGGA,01.00,5158.9396,N,00913.5513,E,1,10,00.7,119.5,M,47.2,M,,*53 $GPRMC,01.00,A,5158.9396,N,00913.5513,E,00.00,144.5,010715,,,A*5C $GPGSV,1,1,04,33,26,210,00,37,29,164,00,39,29,160,00,40,17,127,00*76 $GLGSV,3,1,10,68,36,066,44,69,74,335,39,70,26,270,47,77,17,018,34*63 $GLGSV,3,2,10,78,34,075,42,79,18,125,39,83,06,190,37,84,43,230,41*6C $GLGSV,3,3,10,85,42,304,44,86,07,344,36*67 $GLGSA,A,3,68,69,79,83,85,84,77,78,70,86,,,01.4,00.7,01.2*1C $PORZD,A,002.7*39 $GPZDA,01.00,01,07,2015,00,00*67 RestartKÕÎ$GPGGA,00.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5E $GPRMC,00.00,V,.,N,0.,E,00.00,000.0N*46 $GPGSV,1,1,00*79 $GLGSV,1,1,00*65 $GPGSA,A,1,,,*1E $PORZD,V,999.9*2B $GPGBS,00.00,,,*6F $ALVER,NVS,CSM23,0207*72 $POTST,ID,0268501855,ANT,1,RFG,0,RFR,0*3E $GPGGA,01.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5F $GPRMC,01.00,V,.,N,0.,E,00.00,000.0N*47 $GPGSV,1,1,00*79 $GLGSV,1,1,00*65 $GPGSA,A,1,,,*1E $PORZD,V,999.9*2B $GPZDA,01.0000,00*67 $GPGGA,02.00,.,N,0.,E,0,,,-18.0,M,18.0,M,,*5C $GPRMC,02.00,V,.,N,0.,E,00.00,000.0N*44 The module restarted itself when the leap second occurred. Martin Well it sounds like there are (so far) no major reports of extreme behavior. There still seem to be *lots* of reports of systems that do not handle things gracefully. I wonder if the data above is specific to a chip set (which it probably is) or to how Glonass handles leap seconds (yikes !!!). Bob ___ 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. ___ 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.
[time-nuts] Leap Second results: cheap GPS/1PPS receivers
I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). 1) Parallax PAM-7Q GPS Module https://www.parallax.com/product/28509 When I powered up this board, I see: $GPTXT,01,01,02,u-blox ag - www.u-blox.com*50 $GPTXT,01,01,02,HW UBX-G70xx 0007 EFFFo*1B $GPTXT,01,01,02,ROM CORE 1.00 (59842) Jun 27 2012 17:43:52*59 $GPTXT,01,01,02,PROTVER 14.00*1E $GPTXT,01,01,02,ANTSUPERV=AC SD PDoS SR*20 $GPTXT,01,01,02,ANTSTATUS=DONTKNOW*33 $GPTXT,01,01,02,LLC -FFED---FF79*21 And it appeared to handle the 2015 leap second perfectly: $GPRMC,235959.00,A,4733.25270,N,12208.36733,W,0.329,,300615,,,D*65 $GPGGA,235959.00,4733.25270,N,12208.36733,W,2,09,1.01,308.9,M,-18.8,M,,*61 $GPGLL,4733.25270,N,12208.36733,W,235959.00,A,D*75 $GPRMC,235960.00,A,4733.25285,N,12208.36731,W,0.181,,300615,,,D*67 $GPGGA,235960.00,4733.25285,N,12208.36731,W,2,09,1.01,308.5,M,-18.8,M,,*6F $GPGLL,4733.25285,N,12208.36731,W,235960.00,A,D*77 $GPRMC,00.00,A,4733.25301,N,12208.36743,W,0.312,,010715,,,D*6F $GPGGA,00.00,4733.25301,N,12208.36743,W,2,09,1.01,308.0,M,-18.8,M,,*69 $GPGLL,4733.25301,N,12208.36743,W,00.00,A,D*74 $GPRMC,01.00,A,4733.25317,N,12208.36749,W,0.166,,010715,,,D*62 $GPGGA,01.00,4733.25317,N,12208.36749,W,2,09,1.01,307.6,M,-18.8,M,,*6C $GPGLL,4733.25317,N,12208.36749,W,01.00,A,D*78 2) Reyax as found by multiple sellers on eBay http://www.reyax.com/httpdocs/index.files/GPS_Module.htm When I powered up this board, I see: $GNTXT,01,01,02,u-blox AG - www.u-blox.com*4E $GNTXT,01,01,02,HW UBX-M80xx 0008 *43 $GNTXT,01,01,02,EXT CORE 2.01 (75350) Oct 29 2013 16:15:41*5C $GNTXT,01,01,02,ROM BASE 2.01 (75331) Oct 29 2013 13:28:17*44 $GNTXT,01,01,02,MOD NEO-M8N-0*7A $GNTXT,01,01,02,PROTVER 15.00*01 $GNTXT,01,01,02,GNSS OTP: GPS GLO, SEL: GPS GLO*67 $GNTXT,01,01,02,ANTSUPERV=AC SD PDoS SR*3E $GNTXT,01,01,02,ANTSTATUS=DONTKNOW*2D $GNTXT,01,01,02,FIS 0xEF4015 (73171) found*20 $GNTXT,01,01,02,LLC -FFED---FF69*3E $GNTXT,01,01,02,RF0 dev ok*04 It also appeared to handle the 2015 leap second perfectly: $GNRMC,235959.00,A,4733.25534,N,12208.36945,W,0.052,,300615,,,D*7C $GNGGA,235959.00,4733.25534,N,12208.36945,W,2,12,1.06,315.5,M,-18.8,M,,*7A $GNGLL,4733.25534,N,12208.36945,W,235959.00,A,D*63 $GNRMC,235960.00,A,4733.25539,N,12208.36940,W,0.076,,300615,,,D*78 $GNGGA,235960.00,4733.25539,N,12208.36940,W,2,08,1.23,315.4,M,-18.8,M,,*75 $GNGLL,4733.25539,N,12208.36940,W,235960.00,A,D*61 $GNRMC,00.00,A,4733.25545,N,12208.36936,W,0.011,,010715,,,D*7B $GNGGA,00.00,4733.25545,N,12208.36936,W,2,06,1.59,315.4,M,-18.8,M,,*77 $GNGLL,4733.25545,N,12208.36936,W,00.00,A,D*60 $GNRMC,01.00,A,4733.25546,N,12208.36933,W,0.181,,010715,,,D*74 $GNGGA,01.00,4733.25546,N,12208.36933,W,2,06,1.59,315.3,M,-18.8,M,,*77 $GNGLL,4733.25546,N,12208.36933,W,01.00,A,D*67 3) Adafruit Ultimate GPS Breakout http://www.adafruit.com/products/746 When I powered up this board I see: $PGACK,103*40 $PGACK,105*46 $PMTK011,MTKGRS*08 $PMTK010,001*2E $PMTK010.002*2D This GPS receiver appeared to mess up the 2015 leap second, with a double 5959 and possible receiver reset: (I also had serial communications issues with this board today) $GPGGA,235958.000,t733.2401,N,12208.7780,W,2,7,1.17,257.6,M,-17.3,S000,*62 GPRMC,235958.000,A,4723.2401,N12208.3780,W,0.4x,48.15,300615,,,D*4D $GPGGA,235959.000,4733.2401,N,52208.3778,W,2,7,1.17,257.6,M,-17.3,M,,*64 $GQRMC,235959.000,A,47;3.2401,N,12208.3778,W,0.47,48.15,300615,,,D*44 $GPGGA,235959.000,4733.2402,N,12208.3777,W,2,7,1.17,257.6,M,-17.3,M,,*68- $GPRMC,235959.00,A,4733.2402,N,12208.3777W,0.46,48.17,300615,,,D*49 $GPRMC,0,A,4733.2403,N,12208.3775,W,0.38,4815,010715,,,D*41 $GPGGA,01.000,4733.2403,N,12208.3773,W,2,7,1.17,257.6,],-17.3,M,,*6D $GPRMC,01.000,A,4733.2403,N,12208.3773,W,0.22,48.15,010715,,,D*4D If someone else has data from this model receiver, please let me know. Thanks, /tvb www.LeapSecond.com ___ 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.
Re: [time-nuts] Leap second results: WWVB
Scott Newell newell+timenuts@... writes: My linux parallel port WWVB 'scope got a bit confused at the leap second: I have coded a WWVB receiver according to the published standard. It is all homebrew with an embedded processor and disciplined OXCO. I did not do any display shots (didn't think anyone would be interested) but it gave the L leap second warning yesterday and went 23:59:60 30 JUN 15 before ticking over to July 1. I built this over ten years ago and it has passed through a number of LS events no problem. Since the receiver uses a disciplined OXCO, it only decodes the time signal once per day to ensure time sync and check for warning bits (DST and LS). The rest of the time it ticks along according to the rules. It uses the LS warning bit to switch the time incrementing routine to a special LS version in the last minute of the last hour of the day. ___ 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.
Re: [time-nuts] End Of The World
As expected, on the leap second the display on the 8183 showed 6:59:60 (the 8183-A showed 23:59:60), but the TV400 displayed 7:00:00 at that moment. The TV400 remained one second ahead until it displayed 7:00:03 for a two- second period, then from 7:00:04 forward it was properly synced. On the 2012 event my HP 55300A did the same thing on the IRIG output. The :03 second was repeated and then normal operation resumed. I did attempt to view the event on a 3.5 Tomtom GPS, without much joy. There's a setup screen that shows all SVs in view as well as the current UTC. When it came time to roll from 23:59:59 to 23:59:60 the time line just went blank for 1 second, then rolled to 00:00:00. Their code must be checking for 'invalid' time. Bummer ... -John ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
On 07/01/2015 05:23 PM, Tom Van Baak wrote: I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). 3) Adafruit Ultimate GPS Breakout http://www.adafruit.com/products/746 If someone else has data from this model receiver, please let me know. I have: - MC-1010 (MTK3339, same chipset and code as the adafruit one) - GPS-1513R (Venus 624) -- FUN! - LTE-Lite - old GPS18x The MTK3339 with the same (standard) firmware is also used in the MC-1010. I have output from the 28th and ahead. Same behaviour. $GPGGA,235958.000,5610.4160,N,00929.5793,E,1,10,0.80,84.8,M,43.3,M,,*5E $GPRMC,235958.000,A,5610.4160,N,00929.5793,E,0.01,171.62,300615,,,A*66 $GPGGA,235959.000,5610.4160,N,00929.5793,E,1,10,0.80,84.8,M,43.3,M,,*5F $GPRMC,235959.000,A,5610.4160,N,00929.5793,E,0.01,171.62,300615,,,A*67 $GPGGA,235959.000,5610.4160,N,00929.5793,E,1,10,0.80,84.8,M,43.3,M,,*5F $GPRMC,235959.000,A,5610.4160,N,00929.5793,E,0.01,171.62,300615,,,A*67 $GPGGA,00.000,5610.4160,N,00929.5793,E,1,10,0.80,84.8,M,43.3,M,,*5E $GPRMC,00.000,A,5610.4160,N,00929.5793,E,0.02,171.62,010715,,,A*66 $GPGGA,01.000,5610.4160,N,00929.5793,E,1,10,0.80,84.8,M,43.3,M,,*5F $GPRMC,01.000,A,5610.4160,N,00929.5793,E,0.01,171.62,010715,,,A*64 But, SkyTraq venus 624 (RF Solutions GPS-1513R) is much more fun. It backsteps one minute(!), in addition to the other 'features' it has. $GPGGA,235958.187,5610.4163,N,00929.5757,E,1,11,0.8,84.6,M,41.0,M,,*65 $GPRMC,235958.187,A,5610.4163,N,00929.5757,E,000.0,308.5,300615,,,A*6F $GPGGA,235959.187,5610.4163,N,00929.5757,E,1,11,0.8,84.6,M,41.0,M,,*64 $GPRMC,235959.187,A,5610.4163,N,00929.5757,E,000.0,308.5,300615,,,A*6E $GPGGA,235900.000,5610.4163,N,00929.5757,E,1,11,0.8,84.6,M,41.0,M,,*66 $GPRMC,235900.000,A,5610.4163,N,00929.5757,E,000.0,308.5,300615,,,A*6C $GPGGA,00.187,5610.4163,N,00929.5757,E,1,11,0.8,84.5,M,41.0,M,,*66 $GPRMC,00.187,A,5610.4163,N,00929.5757,E,000.0,308.5,010715,,,A*6C $GPGGA,01.187,5610.4163,N,00929.5757,E,1,11,0.8,84.5,M,41.0,M,,*67 $GPRMC,01.187,A,5610.4163,N,00929.5757,E,000.0,308.5,010715,,,A*6D The Venus on the LTE-Lite, with the updated timing firmware, is sane. I also have the 20MHz output timestamped every 5ms, nothing odd happened. $GPGGA,235959.000,5610.4155,N,00929.5739,E,2,09,0.9,85.4,M,41.0,M,,*6F $GPRMC,235959.000,A,5610.4155,N,00929.5739,E,000.0,000.0,300615,,,D*66 $GPGGA,235960.000,5610.4155,N,00929.5739,E,2,09,0.9,85.4,M,41.0,M,,*65 $GPRMC,235960.000,A,5610.4155,N,00929.5739,E,000.0,000.0,300615,,,D*6C $GPGGA,00.000,5610.4155,N,00929.5739,E,2,09,0.9,85.4,M,41.0,M,,*6E $GPRMC,00.000,A,5610.4155,N,00929.5739,E,000.0,000.0,010715,,,D*64 Old Garmin GPS18x did the same as the MTK3339: $GPRMC,235958,A,5611.0119,N,00932.1092,E,000.0,136.1,300615,002.0,E,D*10 $GPGGA,235958,5611.0119,N,00932.1092,E,2,10,0.8,41.5,M,41.7,M,,*72 $GPRMC,235959,A,5611.0119,N,00932.1093,E,000.0,136.1,300615,002.0,E,D*10 $GPGGA,235959,5611.0119,N,00932.1093,E,2,10,0.8,41.4,M,41.7,M,,*73 $GPRMC,235959,A,5611.0119,N,00932.1094,E,000.0,136.1,300615,002.0,E,D*17 $GPGGA,235959,5611.0119,N,00932.1094,E,2,10,0.8,41.3,M,41.7,M,,*73 $GPRMC,00,A,5611.0120,N,00932.1094,E,000.0,136.1,010715,002.0,E,D*1F $GPGGA,00,5611.0120,N,00932.1094,E,2,10,0.8,41.2,M,41.7,M,,*79 $GPRMC,01,A,5611.0120,N,00932.1094,E,000.0,136.1,010715,002.0,E,D*1E $GPGGA,01,5611.0120,N,00932.1094,E,2,10,0.8,41.2,M,41.7,M,,*78 /Kasper Pedersen ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
Hi Take your OCXO and divide it down to 1 pps. Take the PPS out of your GPSDO Feed both of them into your counter Time the “delta” between the two to the resolution of a 40 year old 5335 ( low ns). Wait 10 seconds Repeat You now have data to a resolution of ~2x10^-10 Shut down the counter, go to bed, come back 100,000 seconds later (a bit over a day) Repeat the same measurement You now have data to ~2x10^-14. Come back each day for week Each day you get another point that is in the low parts in 10^-14 range There are not a lot of other cheap ways you can do that in your basement. Now if you fire up and try this, there are a few things to watch out for. If the two sources are not fairly close in frequency, you will have the PPS signals roll past each other. That’s one of the reasons you take that first 10 second reading. It lets you see if things are close enough for this to make sense without correction. Another subtle issue are sources that drift more than you might like. Unless you can count on the source to be stable to 10 ppm, stretching the points out to a full day apart probably is not a good idea. Lots of fun !! Bob On Jul 1, 2015, at 6:47 PM, Bob Albert via time-nuts time-nuts@febo.com wrote: Okay that makes some sense. I will have to ponder over this and see how it will help. But in any case (which I sort of expected) it's a time consuming procedure, during which the counter isn't available for other use. And when I go to bed I won't know the next day if I might have missed a count. This business of precise time is amazingly interesting, especially since an amateur like me can make some pretty impressive calibrations. The OCXO in the 5328A runs 24/7 but I don't know if it drifts more when the counter is on than it does with the counter off (due perhaps to internal temperature changes). Of course, any drift while the counter is off is not important. Luckily I can often receive 25 MHz WWV so that is handy for calibration. I also have an 8657B with its OCXO although that one isn't running with the unit switched off. (The oven is holding temp 24/7). All advice here eagerly sought and appreciated. On a side note, when I measure the 8657B with the 5328A at 700 MHz it's off by just a few Hz, and stabilizes after a half hour or so. It's the generator that needs to stabilize, not the counter. I am still unsure which unit is closer to being correct but I suspect the counter is closer. Bob On Wednesday, July 1, 2015 3:36 PM, Bob Albert bob91...@yahoo.com wrote: So I can measure the time interval, which should be one second. If I measure 10 intervals, my resolution would be 1 part in 10 million. I think I can set the master oscillator closer than that with beating against WWV. So maybe buying a 1 pps source won't improve anything for me. On Wednesday, July 1, 2015 2:39 PM, Hal Murray hmur...@megapathdsl.net wrote: subscripti...@burble.com said: My linux boxes also did a double 59: Wed Jul 1 00:59:58 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 01:00:00 BST 2015 Wed Jul 1 01:00:01 BST 2015 That's to be expected (unless you have fancy software). Internally, Linux (and most other modern OSes) use UTC. The API doesn't include the TAI offset. There is no way to talk about the extra second. The same problem happens with the switch to summer time. You need the time-zone to tell if the time within the magic extra hour is summer time or winter time. Without the zone, you have to pick one and then there is no way to talk about the other one. To insert the extra second, Linux just sets the time back 1 second, the same way you set your clocks and watches back in the fall. -- These are my opinions. I hate spam. ___ 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. ___ 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. ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
Okay that makes some sense. I will have to ponder over this and see how it will help. But in any case (which I sort of expected) it's a time consuming procedure, during which the counter isn't available for other use. Bob, I suspect you don't quite have it yet. Make one measurement today. It takes a few seconds. Write it down. Then put your counter to other uses, as you wish. No hurry. Then make another measurement a minute, or hour, or day later. It takes a few seconds. The measurement(s) you're making are time interval measurement from-GPS to-OCXO. Not period measurements, OCXO-to-OCXO. The former nicely drift over time and tell you everything you need to know; the latter are boring and don't tell you much. A couple of data points is all you need. Divide time drift by elapsed time and that's the relative frequency error. Easy. Today, Corby was talking about measurements a year apart. The idea is the same. One measures frequency difference between clocks by making 2 (or more) measurements: now and sometime later. /tvb ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). what is the problem with the adafruit board? 73 KJ6UHN Alex On 7/1/2015 4:34 PM, Kasper Pedersen wrote: On 07/01/2015 05:23 PM, Tom Van Baak wrote: I logged NMEA from three cheap ($15-$50) GPS/1PPS receivers, the kind popular with hobbyists: parallax(good), reyax(good), adafruit(bad). ___ 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.
Re: [time-nuts] Basic GPSDO finessing re frequency accuracy
Hi If it’s a GPSDO with a long time constant, the ADEV in the 1-10 second range should be pretty much “all OCXO” and very little influenced by the GPS. Already that makes a bunch of assumptions that may or may not be true: 1) The GPSDO *has* an OCXO and it’s properly designed 2) The unit has been on for a week or so and it locks up fine 3) The position and elevation mask are not so bad that it goes out of GPS lock 4) The environment is stable and you are not on something like a missile. There are probably another dozen things that could be added to that list… Some things to note: 1) As long as you don’t *change* the antenna delay (cable delay) it will have no impact on the frequency accuracy at all. 2) Assuming (more assumptions) that it is an L1 GPSDO, ionosphere will contribute more to the daily drift that minor errors in position. 3) Having many satellites in view at all times is pretty much a requisite for good performance. Antenna location matters. Again, there are a few dozen more things that could go on that list as well. Bob On Jul 1, 2015, at 11:18 AM, Alan Ambrose alan.ambr...@anagram.net wrote: Hi, Does anyone have any data / a feel for how ... antenna delay accuracy and/or elevation mask and/or hold position accuracy ... translate to frequency accuracy for short term measurement i.e. in the 1-10s tau range? That is, which should I focus on, which not? Kind Regards, Alan ___ 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. ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
On Wed, July 1, 2015 12:55 pm, Bob Albert via time-nuts wrote: I am missing something here. How does one use a 1 PPS signal? I see how I can use a 1 MHz or 10 MHz for a time standard but the 1 PPS usage eludes me. Actually you have it backwards. A 1MHz or 10MHz can be a frequency standard, but how do you use it as a time standard? Time implies a clock (time of day) reference, and with just e.g. 10MHz you have 10 million edges per second, you do not know which edge delineates the beginning of a second, so you cannot use that 10MHz to derive time. Unless the pulse is extremely sharp, a minor uncertainty in the shape or amplitude will have profound effects on the timing. The pulse is sharp, but there are other noise sources present on the PPS output from GPS, so you need other tricks such as averaging to make it useful for more than just delineating the second in an approximate sense. I use an HP 5328A with the OCXO and wonder how I can improve its accuracy. The typical way GPS is used is by using the PPS to (effectively) gate a counter of a 10MHz source, and the long term average count is used to steer the 10MHz oscillator so that on average there are 10 million edges between every PPS. As I pointed out the PPS from GPS is kind of noisy (in the time sense, it moves around a bit and isn't actually exactly 1 second apart each time) so you need a lot of averaging. That is what takes place in a GPS disciplined oscillator. The 10MHz output from the GPS disciplined oscillator can then be used as an external reference to the 5328A. If you only have a GPS receiver, and not a full GPS disciplined oscillator, then you can have the 5328 counter measure the frequency of the PPS output, and average that over a long period of time. The long term average will be 1 Hz, so the difference from 1 Hz is the offset of your counter time base from the GPS referenced accurate frequency standard. Again, you would need to take the long term average frequency because there are things such as receiver inaccuracies and inherent atmospheric noise sources which cause small period variations in the time between each PPS output, but those should be random and cancel out with averaging. -- Chris Caudle ___ 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.
[time-nuts] Basic GPSDO finessing re frequency accuracy
Hi, Does anyone have any data / a feel for how ... antenna delay accuracy and/or elevation mask and/or hold position accuracy ... translate to frequency accuracy for short term measurement i.e. in the 1-10s tau range? That is, which should I focus on, which not? Kind Regards, Alan ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
So I can measure the time interval, which should be one second. If I measure 10 intervals, my resolution would be 1 part in 10 million. I think I can set the master oscillator closer than that with beating against WWV. So maybe buying a 1 pps source won't improve anything for me. On Wednesday, July 1, 2015 2:39 PM, Hal Murray hmur...@megapathdsl.net wrote: subscripti...@burble.com said: My linux boxes also did a double 59: Wed Jul 1 00:59:58 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 01:00:00 BST 2015 Wed Jul 1 01:00:01 BST 2015 That's to be expected (unless you have fancy software). Internally, Linux (and most other modern OSes) use UTC. The API doesn't include the TAI offset. There is no way to talk about the extra second. The same problem happens with the switch to summer time. You need the time-zone to tell if the time within the magic extra hour is summer time or winter time. Without the zone, you have to pick one and then there is no way to talk about the other one. To insert the extra second, Linux just sets the time back 1 second, the same way you set your clocks and watches back in the fall. -- These are my opinions. I hate spam. ___ 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. ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
Oh boy Chris, some good information there. I guess my first step would be to get a GPS disciplined source. My preference would be to use an external 10 MHz source. And even if I did, I'd lose it some times of day depending on propagation. Maybe the 1 pps to set my OCXO as close as I can get it, then recheck every few weeks or months to look for long term drift. But the gear is already old so aging has likely stabilized. I assume I can buy a 1 pps source that is practically dead-on accurate and use it when I want to verify my master oscillator. Maybe you can guide me as to the way to do that with minimum fuss and maximum precision. The bottom line here is that I have absolutely no use for such precision. It's just for fun and education. I am one of those nerds who likes to stare at a counter and see that each successive reading is within one count and even do a mental statistical analysis to decide which digit is closer and by how much. It's safer and cheaper than hanging out in bars. Bob On Wednesday, July 1, 2015 8:11 PM, Bob Camp kb...@n1k.org wrote: Hi Take your OCXO and divide it down to 1 pps. Take the PPS out of your GPSDO Feed both of them into your counter Time the “delta” between the two to the resolution of a 40 year old 5335 ( low ns). Wait 10 seconds Repeat You now have data to a resolution of ~2x10^-10 Shut down the counter, go to bed, come back 100,000 seconds later (a bit over a day) Repeat the same measurement You now have data to ~2x10^-14. Come back each day for week Each day you get another point that is in the low parts in 10^-14 range There are not a lot of other cheap ways you can do that in your basement. Now if you fire up and try this, there are a few things to watch out for. If the two sources are not fairly close in frequency, you will have the PPS signals roll past each other. That’s one of the reasons you take that first 10 second reading. It lets you see if things are close enough for this to make sense without correction. Another subtle issue are sources that drift more than you might like. Unless you can count on the source to be stable to 10 ppm, stretching the points out to a full day apart probably is not a good idea. Lots of fun !! Bob On Jul 1, 2015, at 6:47 PM, Bob Albert via time-nuts time-nuts@febo.com wrote: Okay that makes some sense. I will have to ponder over this and see how it will help. But in any case (which I sort of expected) it's a time consuming procedure, during which the counter isn't available for other use. And when I go to bed I won't know the next day if I might have missed a count. This business of precise time is amazingly interesting, especially since an amateur like me can make some pretty impressive calibrations. The OCXO in the 5328A runs 24/7 but I don't know if it drifts more when the counter is on than it does with the counter off (due perhaps to internal temperature changes). Of course, any drift while the counter is off is not important. Luckily I can often receive 25 MHz WWV so that is handy for calibration. I also have an 8657B with its OCXO although that one isn't running with the unit switched off. (The oven is holding temp 24/7). All advice here eagerly sought and appreciated. On a side note, when I measure the 8657B with the 5328A at 700 MHz it's off by just a few Hz, and stabilizes after a half hour or so. It's the generator that needs to stabilize, not the counter. I am still unsure which unit is closer to being correct but I suspect the counter is closer. Bob On Wednesday, July 1, 2015 3:36 PM, Bob Albert bob91...@yahoo.com wrote: So I can measure the time interval, which should be one second. If I measure 10 intervals, my resolution would be 1 part in 10 million. I think I can set the master oscillator closer than that with beating against WWV. So maybe buying a 1 pps source won't improve anything for me. On Wednesday, July 1, 2015 2:39 PM, Hal Murray hmur...@megapathdsl.net wrote: subscripti...@burble.com said: My linux boxes also did a double 59: Wed Jul 1 00:59:58 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 01:00:00 BST 2015 Wed Jul 1 01:00:01 BST 2015 That's to be expected (unless you have fancy software). Internally, Linux (and most other modern OSes) use UTC. The API doesn't include the TAI offset. There is no way to talk about the extra second. The same problem happens with the switch to summer time. You need the time-zone to tell if the time within the magic extra hour is summer time or winter time. Without the zone, you have to pick one and then there is no way to talk about the other one. To insert the extra second, Linux just sets the time back 1 second, the same way you set your clocks and watches back in the fall. -- These are my opinions. I hate spam.
Re: [time-nuts] Leap second results: WWVB
At 09:23 PM 6/30/2015, Tom Van Baak wrote: That's a nice WWVB result. Yes, the triple marker pulse looks is correct for a positive leap second. What did you use for a receiver? The receiver module and ferrite bar antenna from a Westclox 70026 desktop 'atomic clock', as available from Walmart for about $12. -- newell N5TNL ___ 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.
Re: [time-nuts] [Bulk] Leap second results: LH screenshot
J. L. Trantham kirjoitti: Interestingly, the time is 23:59:60 but the UTC ofs is still 16. I guess it increments to 17 at the end of that operation, i.e., at 00:00:00. That is exactly how it should be. See my video of 2012 leap sec: https://www.youtube.com/watch?v=DbvMZikqtI4 -- 73s! Esa OH4KJU ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
Okay that makes some sense. I will have to ponder over this and see how it will help. But in any case (which I sort of expected) it's a time consuming procedure, during which the counter isn't available for other use. And when I go to bed I won't know the next day if I might have missed a count. This business of precise time is amazingly interesting, especially since an amateur like me can make some pretty impressive calibrations. The OCXO in the 5328A runs 24/7 but I don't know if it drifts more when the counter is on than it does with the counter off (due perhaps to internal temperature changes). Of course, any drift while the counter is off is not important. Luckily I can often receive 25 MHz WWV so that is handy for calibration. I also have an 8657B with its OCXO although that one isn't running with the unit switched off. (The oven is holding temp 24/7). All advice here eagerly sought and appreciated. On a side note, when I measure the 8657B with the 5328A at 700 MHz it's off by just a few Hz, and stabilizes after a half hour or so. It's the generator that needs to stabilize, not the counter. I am still unsure which unit is closer to being correct but I suspect the counter is closer. Bob On Wednesday, July 1, 2015 3:36 PM, Bob Albert bob91...@yahoo.com wrote: So I can measure the time interval, which should be one second. If I measure 10 intervals, my resolution would be 1 part in 10 million. I think I can set the master oscillator closer than that with beating against WWV. So maybe buying a 1 pps source won't improve anything for me. On Wednesday, July 1, 2015 2:39 PM, Hal Murray hmur...@megapathdsl.net wrote: subscripti...@burble.com said: My linux boxes also did a double 59: Wed Jul 1 00:59:58 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 00:59:59 BST 2015 Wed Jul 1 01:00:00 BST 2015 Wed Jul 1 01:00:01 BST 2015 That's to be expected (unless you have fancy software). Internally, Linux (and most other modern OSes) use UTC. The API doesn't include the TAI offset. There is no way to talk about the extra second. The same problem happens with the switch to summer time. You need the time-zone to tell if the time within the magic extra hour is summer time or winter time. Without the zone, you have to pick one and then there is no way to talk about the other one. To insert the extra second, Linux just sets the time back 1 second, the same way you set your clocks and watches back in the fall. -- These are my opinions. I hate spam. ___ 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. ___ 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.
Re: [time-nuts] Leap second results: LH screenshot
At 07:15 AM 7/1/2015, J. L. Trantham wrote: Interestingly, the time is 23:59:60 but the UTC ofs is still 16. I guess it increments to 17 at the end of that operation, i.e., at 00:00:00. I just pulled the next screenshot to check, and you're correct: https://www.n5tnl.com/time/leap_2015/tbolt_second_after.gif Hadn't noticed it myself. -- newell N5TNL ___ 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.
Re: [time-nuts] Leap Second results: cheap GPS/1PPS receivers
time-nuts@febo.com said: I am missing something here. How does one use a 1 PPS signal? I see how I can use a 1 MHz or 10 MHz for a time standard but the 1 PPS usage eludes me. Unless the pulse is extremely sharp, a minor uncertainty in the shape or amplitude will have profound effects on the timing. It's a digital signal, not a sine wave. For a TBolt, it's 10 microseconds wide. I use an HP 5328A with the OCXO and wonder how I can improve its accuracy. You can't feed it into the ext-osc input, but you can check the calibration by measuring the time between pulses. If the measured time is longer than a second, your internal clock is running slow. -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] End Of The World
I'm happy to report that I did not get blasted away, but I did record what I think is an odd catch-up on a display clock. I have a Spectracom TV400 display clock literally sitting on top of and connected to a Spectracom 8183 (set to Central time zone) via RS-485 and 10' of shielded, twisted-pair wire. Below the 8183 is an 8183-A set to UTC. I grabbed my iPhone and videoed the three a little bit on both sides of the leap second while listening to WWV on 10 MHz with a Kinemetrics/TrueTime WVTR MK V. As expected, on the leap second the display on the 8183 showed 6:59:60 (the 8183-A showed 23:59:60), but the TV400 displayed 7:00:00 at that moment. The TV400 remained one second ahead until it displayed 7:00:03 for a two-second period, then from 7:00:04 forward it was properly synced. I know only enough about electronics to be potentially dangerous, so I have no explanation for this behavior. Perhaps someone knows why this happened and can explain? Thanks much to all for the enjoyment of and knowledge I've gained from reading postings on this list! David Stell Oklahoma City -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Tuesday, June 30, 2015 8:04 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] End Of The World Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ 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. ___ 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.
Re: [time-nuts] End Of The World
On Wed, Jul 1, 2015 at 1:03 AM, Bob Camp kb...@n1k.org wrote: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? I was eagerly connecting to various things to watch for problems when everything stopped responding precisely at the end of the leapsecond. Turned out my cell phone-- an old android 2.3 device on the sprint network-- dropped off the network (looked like it was up but couldn't make or receive calls and no data was getting through). I waited 15 minutes to see if it would recover on its own, but it did not during that time. OTOH if it went out for 15 minutes otherwise I might not have thought to much of it-- so no proof that it was due to the leapsecond; very coincidental timing if not. :) ___ 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.
[time-nuts] End Of The World
Lady Heather just went told me 23:59:59 , 00:00:00 and stayed there for 2 secs, No 23:59:60 :-( Le 1 juil. 2015 à 03:03, Bob Camp kb...@n1k.org a écrit : Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ 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. Ceux qui sont prêts à abandonner une liberté essentielle pour obtenir une petite et provisoire sécurité, ne méritent ni liberté ni sécurité. Benjimin Franklin ___ 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.
Re: [time-nuts] End Of The World
I drove past the US Naval Observatory on Massachusetts Avenue in Washington this evening. Their big LED clock by the main entrance was dark and someone appeared to be working on it. The leap second must have broken the USNO clock! Dan Schultz N8FGV ---original message--- Date: Tue, 30 Jun 2015 21:03:30 -0400 From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: [time-nuts] End Of The World Message-ID: 66d6b7a9-aa39-4d5d-8a34-dd5f78488...@n1k.org Content-Type: text/plain; charset=us-ascii Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ 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.
Re: [time-nuts] End Of The World
Hi, Some of us have found ourselves in Besancon this week for the EFTS, which is extraordinary but not strange. I found myself explaining Delta and Omega counter responses with hockey-puck ADEV responces on the whiteboard for the lab-session. Cheers, Magnus On 07/01/2015 03:03 AM, Bob Camp wrote: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ 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. ___ 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.
Re: [time-nuts] End Of The World
The Heol card worked in my 2100 and handled the event like a champ. I was surprised that the NIST site only fixed itself about 5 minutes ago though. Apparently Google has been inserting about .2 of a second for the last few updates slowly working up to this which I thought was interesting. HAPPY LEAP EVENT EVERYONE!! Respectfully, Sean Gallagher Malware Analyst 571-340-3475 -- Original Message -- From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: 6/30/2015 9:03:30 PM Subject: [time-nuts] End Of The World Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ 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. ___ 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.
[time-nuts] Leap Second video
Here is a short video of the leap second compared to a regular clock. http://youtu.be/725ECUOXqeY -Arthur ___ 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.
