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Reports until 22:40, Tuesday 25 June 2019
H1 CDS
david.barker@LIGO.ORG - posted 22:40, Tuesday 25 June 2019 (50197)
h1iopiscey DAC-Duotone loopback was turned on after restart Monday 17th June

During some SDF cleanup work today I noticed that the OBSERVE.snap file for h1iopiscey was modified Monday evening 17th June to permit the DAC Duotone loopback to be ON. 

Following the kernel panic of h1iscey that evening, the safe.snap had turned the DACDT ON. Transitioning to the OBSERVE.snap reference raised a sdf-diff, because this file had this setting as OFF. The operator accepted the new ON setting to transition to observation mode.

This channel is not in the DAQ, but a rudimentary trend can be obtained from the hourly autoburt (see below). This shows that the DAC DT loop back has been OFF since the start of O3, transitioning to ON Monday 17jun2019.

I'll follow up with the calibration group as to what this setting should be.

I will also work on making all IOP SDFs having only a safe.snap file, with OBSERVE.snap being a symbolic link to it.

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