Topic:
Test to examine APT transmitter effect on HIRS instrument

Date/Time(UTC) Message Issued:
9 May 2007, 1600 UTC

Satellite(s) Involved:
NOAA-18

Instrument(s) Involved:
HIRS, APT

Product(s) Involved/Affected:
loss of data

Date/Time(UTC) of Initial Implementation:
10 May 2007, TBD

Details/Specifics of Change: The HIRS instrument noise level has quieted down and NOAA is ready for Satellite Operations Control Center (SOCC) to proceed with the test of APT transmitter effects on the HIRS instrument noise. On 10 May, the following test scenario will be executed. Specific time period and orbits impacted by the test will be reported in a separate email.

Proposed test scenario:
The instrument will be placed in space view for two orbits in order to provide a uniform background and then we will systematically turn-on/off the various transmitters and monitor the noise looking for any noise spikes. After the command sequence has been run, the instrument will be returned to full-scan mode.

First command sequence about 9 minutes:
- Park HIRS at space view, wait 2 minutes
- Turn VTX2 off, wait 2 minutes
- Turn BTX1 off, wait 2 minutes
- Turn BTX1 on, wait 2 minutes
- Turn VTX1 on, wait 2 minutes
- Turn VTX1 off, wait 10 seconds
- Turn VTX2 on

HIRS remains in space view mode

Second command sequence about 9 minutes:
- Turn VTX2 off, wait 10 seconds
- Turn BTX2 on, wait 2 minutes
- Turn BTX2 off, wait 2 minutes
- Turn BTX1 on, wait 2 minutes
- Turn VTX2 on, wait 10 seconds
- HIRS to full scan mode

Contact Person(s) Name/Email/Phone Number for Questions:
Emily Harrod Emily.Harrod@noaa.gov 301-817-3882
Renee Smith-Dearing Renee.Smith@noaa.gov 301-817-4117

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
     http://www.oso.noaa.gov/poes/index.htm - SOCC polar satellite status
   http://www.oso.noaa.gov/goes/index.htm - SOCC geostationary satellite status
     http://www.oso.noaa.gov/daily-news/index.asp - SOCC morning reports

-- 
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*
* Emily D. Harrod
* NOAA/NESDIS/OSDPD/IPD
* Computer Operations Branch
* Pre-Product Processing Group
* E/SP11, NSOF, room 1460
* 4231 Suitland Road
* Suitland, Maryland  20746-4304
* USA
* voice 301-817-3882
* fax   301-817-3902
* email Emily.Harrod@noaa.gov
*
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