Subject: Administrative: GOES-12 (GOES-South America) Imager --f46d0444ec39a1ecc204c1bced01 Content-Type: text/plain; charset=ISO-8859-1 Topic: GOES-12 (GOES-South America) Imager Electronics Side Swap is scheduled for June 6, 2012 Date/Time Issued: June 5, 2012 1730 UTC Product(s) or Data Impacted: GOES-12 (GOES-South America) Imager Data Date/Time of Initial Impact: June 6, 2012 1615 UTC Date/Time of Expected End: June 6, 2012 1645 UTC Length of Outage: 30 minutes Details/Specifics of Change: The Office of Satellite and Product Operations (OSPO) decided to switch the GOES-12 (GOES-South America) Imager electronics side, based on the manufacturer's recommendation as a potential remedy to mitigate cycle slips. This side switch operation will be performed on Wednesday, June 6, 2012 during the 1615 UTC housekeeping period. The operation is expected to take approximately 30 minutes. GOES-12 (GOES-South America) had a 5-year expected life span, but it has been in service for more than 9 years and is showing serious signs of aging. In late April 2012, imager cycle slips increased to daily occurrences, corrupting on average 3-5 frames every day and spreading to 15-20 frames per day during the past week. A cycle slip is the shifting of a segment of the image approximately 5.6 degrees (1 imager cycle) to the east or west. It occurs because imager electronics lose count of the scan mirror position. These segment shifts can happen more than once in the same image as the instrument corrects itself during a space look and then repeats the same anomaly at a later time. Please see http://cimss.ssec.wisc.edu/goes/blog/archives/10307 for an example. Please note: Imager Side 2 electronics has a different set of detectors, so users could use the new side-2 offline calibration coefficients and/or the new look-up table to convert GOES-12 Imager GVAR data into brightness temperatures. A new look-up table and calibration coefficients for the side-2 detectors have been calculated and are available on the OSPO Calibration website: http://www.oso.noaa.gov/goes/goes-calibration/gvar-conversion.htm Please remember to use the new coefficients or the look-up table after June 6, 2012 at 1615 UTC. ESPC Operations contact information: ESPCOperations@noaa.gov and 301-817-3880 Web Site(s) for applicable information: See http://www.ssd.noaa.gov/PS/SATS/messages.html for this and other satellite related messages. See http://www.ssd.noaa.gov/PS/SATS/GOES/SA/ for GOES-12 Information and Schedules See http://www.oso.noaa.gov/goes/goes-calibration/gvar-conversion.htm for new look-up table and calibration coefficients See http://www.oso.noaa.gov/goes/goes-calibration/goes-imager-srfs.htm for side-2 Spectral Response Functions (SRF) See http://cimss.ssec.wisc.edu/goes/blog/archives/10307 for example of cycle slips --f46d0444ec39a1ecc204c1bced01 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Topic: GOES-12 (GOES-South America) Imager Electronics Side Swap is sc= heduled for June 6, 2012

Date/Time Issued: June 5,= 2012 1730 UTC=A0

Product(s) or Data Impacted: GOE= S-12 (GOES-South America) Imager Data

Date/Time of Initial Impact: June 6, 2012 1615 UTC

Date/Time of Expected End: June 6, 2012 1645 UTC
=

Length of Outage: 30 minutes

Details/Specifics of Change: The Office of Satellite and Product Operations= (OSPO) decided to switch the GOES-12 (GOES-South America) Imager electroni= cs side, based on the manufacturer's recommendation as a potential reme= dy to mitigate cycle slips. =A0This side switch operation will be performed= on Wednesday, June 6, 2012 during the 1615 UTC housekeeping period. =A0The= operation is expected to take approximately 30 minutes. =A0=A0

GOES-12 (GOES-South America) had a 5-year expected life= span, but it has been in service for more than 9 years and is showing seri= ous signs of aging. =A0In late April 2012, imager cycle slips increased to = daily occurrences, corrupting on average 3-5 frames every day and spreading= to 15-20 frames per day during the past week.=A0

A cycle slip is the shifting of a segment of the image = approximately 5.6 degrees (1 imager cycle) to the east or west. =A0It occur= s because imager electronics lose count of the scan mirror position. =A0The= se segment shifts can happen more than once in the same image as the instru= ment corrects itself during a space look and then repeats the same anomaly = at a later time. =A0Please see http://cimss.ssec.wisc.edu/goes/blog/= archives/10307 for an example.

Please note: Imager Side 2 electronics has a different = set of detectors, so users could use the new side-2 offline calibration coe= fficients and/or the new look-up table to convert GOES-12 Imager GVAR data = into brightness temperatures. =A0A new look-up table and calibration coeffi= cients for the side-2 detectors have been calculated and are available on t= he OSPO Calibration website: =A0http://www.oso.noaa.go= v/goes/goes-calibration/gvar-conversion.htm

Please remember to use the new coefficients or the look= -up table after June 6, 2012 at 1615 UTC. =A0

ESPC= Operations contact information: =A0ESPCOperations@noaa.gov and 301-817-3880

Web Site(s) for applicable information:
See <= a href=3D"http://www.ssd.noaa.gov/PS/SATS/messages.html" target=3D"_blank">= http://www.ssd.noaa.gov/PS/SATS/messages.html =A0for this and other sat= ellite related messages.
See http://www.ssd.noaa.gov/PS/SATS/GOES/SA/ for GOES-12 Information a= nd Schedules=A0
See http://www.oso.noaa.gov/= goes/goes-calibration/gvar-conversion.htm for new look-up table and cal= ibration coefficients
See http://www.oso.noaa.gov/goes/goes-calibratio= n/goes-imager-srfs.htm for side-2 Spectral Response Functions (SRF)
See http://cimss.ssec.wisc.edu/goes/blog/archives/10307 for= example of cycle slips
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