> > svn64 alive and well > > Using sirfdemo pc software coupled with sirf iv gps receiver I picked up the first signal from svn64 (now > assigned prn30). > The sat was launched from cape canavral (airforce station) florida last thursday evening 2-20-14 about 17:55pdt. > The gps control people seem to be turning on the satellites transmitter intermittantly. > The new satellite will not be in its final orbit for approximately 30 days and not usable till about 36 days > from its launch > > date. > > My first reception was at 23:32:22pdt > > gps time error freq-drift date time pdt > > 4.4716290517e-010,-1.1166002510e-014 <at> 02/21/2014 23:32:22 > 2.7434175598e-010,-5.1373205549e-014 <at> 02/22/2014 00:57:22 > 2.7264644019e-010,-5.1373205549e-014 <at> 02/22/2014 00:57:52 > 2.7202887741e-010,-5.2401886405e-014 <at> 02/22/2014 00:58:22 > 2.7003760573e-010,-5.2401886405e-014 <at> 02/22/2014 00:58:52 > 2.6877996045e-010,-5.2401886405e-014 <at> 02/22/2014 00:59:22 > 2.6416859445e-010,-5.2401886405e-014 <at> 02/22/2014 01:00:52 > 2.5693992947e-010,-5.3422655975e-014 <at> 02/22/2014 01:02:52 > 2.5624543494e-010,-5.3422655975e-014 <at> 02/22/2014 01:03:22 > 2.5421537401e-010,-5.3422655975e-014 <at> 02/22/2014 01:03:52 > 2.4365104104e-010,-5.4384875238e-014 <at> 02/22/2014 01:06:52 > 2.4196987886e-010,-5.5335398671e-014 <at> 02/22/2014 01:07:22 > 2.3208415713e-010,-5.6217685129e-014 <at> 02/22/2014 01:10:22 > 2.3084736806e-010,-5.6217685129e-014 <at> 02/22/2014 01:10:52 > 2.1308972996e-010,-5.7062414147e-014 <at> 02/22/2014 01:15:52 > 2.1229085616e-010,-5.7062414147e-014 <at> 02/22/2014 01:16:22 > 2.1024898532e-010,-5.7873397372e-014 <at> 02/22/2014 01:16:52 > 1.7422816710e-010,-6.0095673013e-014 <at> 02/22/2014 01:26:52 > 1.4985197051e-010,-6.1364392842e-014 <at> 02/22/2014 01:33:52 > -8.2096225744e-011,-6.4458299267e-014 <at> 02/22/2014 02:33:22 > -8.7252889686e-011,-6.4458299267e-014 <at> 02/22/2014 02:34:52 > -8.8348680774e-011,-6.4458299267e-014 <at> 02/22/2014 02:35:22 > -1.0635115866e-010,-6.3795634899e-014 <at> 02/22/2014 02:39:52 > -1.0947714477e-010,-6.3795634899e-014 <at> 02/22/2014 02:40:52 > -1.2733387921e-010,-6.2957112939e-014 <at> 02/22/2014 02:45:22 > > This is a complete list of all that was received from the new prn30 satellite (so far). perhaps there saving > power till solar > > pannel deployment? or are saving power to charge batterys after just deploying solar pannels? > > The numbers were cut an pasted from message id 30 (nl sv state data) from the sirfdemo pc software logging feature. > I've been monitoring this information for the last 8 weeks logging many days of satellite data. > > It appears that gps time error gets updated from the satellite broadcast navagation message at least daily. > I believe that the gps receiver then computes the satellite frequency drift (including doppler shift) and > computes gps time > > error till the next satellite navagation broadcast message updates the accumulated time error. > > Atomic clocks in gps orbit run 45us fast perday due to less gravity but loose 8 us per day do to > there high velocity. the net result is 37us per daily. > > It looks like the new satellite clock is keeping excellant time for not being in orbit yet.. perhaps it is > allready high > > enough above earth to not experience the slower time of earths gravity? > > The old Prn30 has been flagged unusable for years. but data was still received and logged with sirfdemo. > > This is the last data from the old satellite prn30 (norad number 34661) whose transmissions became > intermittant the last week > > (control operators turning it off and on). > > gps time error frequency drift > 6.7348954278e-004,2.8731554896e-012 <at> 02/21/2014 11:21:28 = last intermittant message from the old > prn30 satellite. > > My gps receiver is a bu-353s4 (sirf-4) usb dongle that is available on ebay for about $40 dollars. My old > sirfIII worked a > > little better (globalsat holux gr-213u). the new sirf IV spitts unwanted data randomly into log file. > random data labeled > > unk:hexadecimal strings no help on internet but many complaints.. sirfdemo software is still > downloadable from the internet. > > Nothing else has been received sense 02:45. I dont know if the sat is still visable to the usa right now or if > the > > transmissions have been disabled .. > There isn't any information on the internet yet.. No norad satellite numbers (svn64) published for > tracking it yet. > > Enjoy. hope my tabs and spaces keep data aligned.. > > Hello Tom, Just wondering if we are looking at the same data? I have been using SiRFDemo with a BU353S4 and looking at the Message 30 output. Currently (2pm MT 2Mar2014) PRN30 clock bias is 1.3294214026e-006 sec and rate is 3.6977287551e-012 sec/sec.
Entire output of the message is - 30,30,7.45629999999e+004,- 1.1858809451e+007,- 2.1249722627e+007,1.1326906314e+007,1.1932198375e+003,7.7622948298e+002,2.7 047409217e+003,1.3294251003e-006,3.6977287551e- 012,4,4.0960000000e+005,1.0816000000e+004,1.6134907007e+000 These values don't seem to be out of line with the other SV being tracked. Just wondering if the clock bias has drifted this far off and drift now 2 orders of magnitude worse than when you made your observations? Regards, Skip Withrow _______________________________________________ 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.