NOAA-18, HIRS &, APT, Repeat APT/HIRS Noise Association Test Today, 15 June 2007- Issued: 15 June 2007; 1830 UTC

Repeat of test to examine APT transmitter effect on HIRS instrument

Date/Time(UTC) Message Issued:
15 June 2007, 1830 UTC

Satellite(s) Involved:

Instrument(s) Involved:

Product(s) Involved/Affected:
loss of data

Date/Time(UTC) of Initial Implementation:
15 June 2007, 2017 UTC, approximate test start time
15 June 2007, 2211 UTC, approximate test end time

Details/Specifics of Change:
SOCC has announced that the HIRS instrument on NOAA-18 has quieted down and they will attempt to repeat the noise association test today, June 15.

Information from SOCC: If we can get the details arranged in time we will be re-executing the NOAA-18 HIRS test where we turn off and on the VTX and BTX transmitters. The first pass (orbit 10666) runs from 20:17:50z to 20:29:50z. The HIRS will remain parked at the end of this pass. The second pass(orbit 10667) is at 21:57:30z to 22:10:30z. At the end of this pass the spacecraft should be back to its original configuration.

***** Information from May 10 test - same procedure will be followed *****

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 301-817-3882
Renee Smith-Dearing 301-817-4117
Jim Walters 301-817-4033

Web site(s) that contain other relevant information (where applicable): - History of level 1B notices - All user notices - SOCC polar satellite status - SOCC geostationary satellite status - SOCC morning reports

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