20:19 UTC this pass was a real mess …

18:36 UTC looked good from AOS till 18:47 UTC

Starting on 12 February 2010, the instability in NOAA-17 AVHRR Scan Motor caused excessive amounts of MIRP rephase events. The rephase events result in data loss. Users reported to receive images with a sudden displacement and/or data gaps. They also experienced failures in processing NOAA-17 direct readout data.

17:01 UTC very low eastern pass

On 9 March 2010, the engineers disabled NOAA-17 MIRP rephase function to mitigate the data loss events. Since then, they have had images with and without good quality. The typical images with a quality issue tend to have a “bar code” effect. With the rephase disabled, the MIRP is no longer performing automatic correction for the drift in the AVHRR motor rotational period. The result is that the AVHRR data boundaries may not line up correctly with output frames from the MIRP.

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