Re: PRN01? Still usable?

On Mar 20, 5:55 pm, s_an...@xxxxxxxxxxx wrote:
On Mar 20, 11:04 am, Sam Wormley <sworml...@xxxxxxxxx> wrote:



Dan Fletcher wrote:
Sam,

Hence, my confusion, especially in light of this where it was set unusable.

NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2008030 NANU TYPE: GENERAL
*** GENERAL MESSAGE TO ALL GPS USERS *** GPS SATELLITE SVN32 (PRN01) WAS SET
UNUSABLE ON JDAY 077 (17 MAR 2008) AT 1953Z. SVN32 (PRN01) WAS
DECOMMISSIONED
FROM ACTIVE SERVICE ON JDAY 077 (17 MAR 2008) AT 2200Z. PRN01 WILL BE
AVAILABLE FOR FUTURE SATELLITE SERVICE.

So, not trying to be difficult! Just wondering why, if the bird is unusable,
I'm still using it for positioning. If I'm missing something, just help me
understand it; I'm trying to learn!

Thanks.

"Sam Wormley" <sworml...@xxxxxxxxx> wrote in message
news:idlEj.83544$yE1.30538@xxxxxxxxxxxx
Dan Fletcher wrote:
Fired up three different GPS units today when PRN01 was in range, and all
three locked onto it and were using is for positioning. Decommissioned? I
think not!

What is everyone else seeing?
NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2008028 NANU TYPE: GENERAL
*** GENERAL MESSAGE TO ALL GPS USERS ***
SVN32 (PRN01) FORECAST OUTAGE JDAY 077/1930Z UNTIL FURTHER NOTICE.
GPS SATELLITE SVN32 (PRN01) WILL BE UNUSABLE NO EARLIER THAN JDAY 077 (17
MAR 2008) BEGINNING 1930Z UNTIL FURTHER NOTICE.
*** GENERAL MESSAGE TO ALL GPS USERS ***

POC:
CIVILIAN - NAVCEN AT 703-313-5900, HTTP://WWW.NAVCEN.USCG.GOV
MILITARY - GPS OPERATIONS CENTER at HTTP://GPS.AFSPC.AF.MIL/GPSOC, DSN
560-2541,
COMM 719-567-2541, gps_supp...@xxxxxxxxxxxxxxxx,
HTTP://gps.afspc.af.mil/gps
MILITARY ALTERNATE - JOINT SPACE OPERATIONS CENTER, DSN 276-9994,
COMM 805-606-9994, JSPOCCOMBAT...@xxxxxxxxxxxxxxxxx

UNCLASSIFIED
GPS OPERATIONAL ADVISORY 079.OA1
SUBJ: GPS STATUS 19 MAR 2008

1. SATELLITES, PLANES, AND CLOCKS (CS=CESIUM RB=RUBIDIUM):
A. BLOCK I : NONE
B. BLOCK II: PRNS 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
PLANE : SLOT D1, C2, D4, B5, C1, A4, A3, A1, E3, D2, B4, F3, F1, F2
CLOCK : RB, CS, RB, RB, RB, RB, CS, CS, RB, RB, RB, RB, RB, RB
BLOCK II: PRNS 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29
PLANE : SLOT B1, C4, E4, C3, E1, D3, E2, F4, D5, A5, F5, A6, B3, C6
CLOCK : RB, RB, RB, RB, RB, RB, RB, RB, CS, RB, RB, CS, RB, RB
BLOCK II: PRNS 30, 31, 32
PLANE : SLOT B2, A2, E5
CLOCK : CS, RB, RB
2. CURRENT ADVISORIES AND FORECASTS :
A. FORECASTS: FOR SEVEN DAYS AFTER EVENT CONCLUDES.
NANU MSG DATE/TIME PRN TYPE SUMMARY (JDAY/ZULU
TIME START - STOP)

2008025 010001Z MAR 2008 10 FCSTMX 065/1300-066/0100
2008026 051812Z MAR 2008 10 FCSTSUMM 065/1517-065/1812
2008027 122215Z MAR 2008 25 FCSTMX 077/2200-078/1000
2008031 180233Z MAR 2008 25 FCSTSUMM 077/2226-078/0219
B. ADVISORIES:
NANU MSG DATE/TIME PRN TYPE SUMMARY (JDAY/ZULU
TIME START - STOP)

C. GENERAL:
NANU MSG DATE/TIME PRN TYPE SUMMARY (JDAY/ZULU
TIME START - STOP)

2008024 261809Z FEB 2008 GENERAL /-/
2008028 131929Z MAR 2008 GENERAL /-/
2008029 160248Z MAR 2008 07 LAUNCH /-/
2008030 172219Z MAR 2008 GENERAL /-/
3. REMARKS:
A. THE POINT OF CONTACT FOR GPS MILITARY OPERATIONAL SUPPORT IS THE GPS
OPERATIONS CENTER AT (719)567-2541 OR DSN 560-2541.
B. CIVILIAN: FOR INFORMATION, CONTACT US COAST GUARD NAVCEN AT
COMMERCIAL (703)313-5900 24 HOURS DAILY AND INTERNET
HTTP://WWW.NAVCEN.USCG.GOV
C. MILITARY SUPPORT WEBPAGES CAN BE FOUND AT THE FOLLOWING
HTTP://GPS.AFSPC.AF.MIL/GPS OR HTTP://GPS.AFSPC.AF.MIL/GPSOC

Off the top of my head, I don't know more... but will keep my ears
open.

- Sam- Hide quoted text -

- Show quoted text -

The following is the first and last ephemeris updates for PRN-1 from
yesterday 3/19/08 from
the CORS global navigation files:
(seehttp://geodesy.noaa.gov/CORS/download2/)

2 NAVIGATION DATA RINEX
VERSION / TYPE
CCRINEXN V1.6.0 UX CDDIS 20-MAR-08 02:52 PGM / RUN
BY / DATE
IGS BROADCAST EPHEMERIS FILE
COMMENT
0.1118E-07 0.7451E-08 -0.5960E-07 -0.5960E-07 ION
ALPHA
0.9011E+05 0.0000E+00 -0.1966E+06 -0.6554E+05 ION
BETA
-0.465661287308E-08-0.106581410364E-13 405504 1471 DELTA-UTC:
A0,A1,T,W
14 LEAP
SECONDS
END OF
HEADER
1 08 3 19 0 0 0.0 0.193218700588E-03 0.261479726760E-11
0.000000000000E+00
0.136000000000E+03 0.893437500000E+02
0.371658338204E-08-0.308460744326E+01
0.471994280815E-05 0.701391987968E-02 0.111348927021E-04
0.515361769486E+04
0.259200000000E+06 0.189989805222E-06-0.304143918845E
+01-0.894069671631E-07
0.991567696923E+00 0.177468750000E+03-0.178219041623E
+01-0.756245786387E-08
0.205008539429E-09 0.100000000000E+01 0.147100000000E+04
0.000000000000E+00
0.570000000000E+01 0.630000000000E+02-0.372529029846E-08
0.136000000000E+03
0.252018000000E+06 0.400000000000E+01 0.000000000000E+00
0.000000000000E+00

1 08 3 19 22 0 0.0 0.193433836102E-03 0.261479726760E-11
0.000000000000E+00
0.770000000000E+02 0.486250000000E+02 0.363872299599E-08
0.218482882961E+01
0.244751572609E-05 0.701174722053E-02 0.120941549540E-04
0.515361517716E+04
0.338400000000E+06 0.540167093277E-07-0.304203948664E
+01-0.137835741043E-06
0.991584723827E+00 0.159250000000E+03-0.178251724383E
+01-0.743566686823E-08
0.628597612185E-10 0.100000000000E+01 0.147100000000E+04
0.000000000000E+00
0.400000000000E+01 0.630000000000E+02-0.372529029846E-08
0.770000000000E+02
0.333198000000E+06 0.400000000000E+01 0.000000000000E+00
0.000000000000E+00

The fact that there is data means PRN-1 was broadcasting, the "63" in
the 2nd col, 2nd to last
row is the health indication of Unhealthy. Your receiver might track
but it should not use it.

Hi Tom,

As of today, it's no longer showing up in the Yuma and SEM format
almanacs.

The Trimble receivers we have (SV6, SV8) both indicate "63" for PRN
1's health and are being excluded.

2SOPS will typically set the bird unhealthy *before* issuing the NANU.
In the case of a bird returning to service, the reverse is also true
(set healthy prior to canceling the NANU).

Decommissioning is a special case, hence the "GENERAL" Nanu Type.


Regards,
Jon
.

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