Administrative, NOAA-19,All Instruments, Daily Clock Correction Bias, 21 July 2009 - Issued: 17 July 2009 1900 UTC

Topic:
Daily Spacecraft TIP Clock Drift Corrections

Date/Time(UTC) Message Issued:
17 July 2009, 1900 UTC

Satellite(s) Involved:
NOAA-19

Instrument(s) Involved:
All Instruments

Product(s) Involved/Affected:
All Products.

Date/Time(UTC) of Initial Implementation:
21 July 2009, Time 0000 UTC

Details/Specifics of Change:
The Satellite Operations Control Center (SOCC) has announced that effective at 0000Z on 21 July 2009, "the daily 24 hour ETCUP (Elapsed Time Clock Update) will be biased to control and minimize the daily drift rate of the NOAA-19 TIP clock. As of 9 July, the NOAA-19 TIP Clock error was about -580 milliseconds and the drift rate is presently about -3 milliseconds per day. In order to minimize the daily drift and keep the TIP clock error at a low level, a bias of +3.05 milliseconds will be added to the daily ETCUP beginning on 21 July 2009. This will enable the TIP clock error to be stabilized at a nearly constant value indefinitely without further intervention."

All level 1B data users must note that on 4 June, the Information Processing Division began adjusting data time codes to remove most of the clock drift error. This update will continue but modifications will be made to reflect the SOCC ETCUP daily bias.
Contact Person(s) Name/Email/Phone Number for Questions:
Emily Harrod Emily.Harrod@noaa.gov 301-817-3882 IPD Level 1B operations support
Carl Gliniak Carl Gliniak 301-817-4207 SOCC spacecraft operations

Web site(s) that contain other relevant information (where applicable):
http://www.osdpd.noaa.gov/PSB/PPP/PPP.html - History of level 1B notices
http://www.ssd.noaa.gov/PS/SATS/messages.html - All user notices