J. Kissel, Nutsinee
Dan found glitches in SR3 T2 last night and it seems like we have been having trouble locking ever since so we investgated. SR3 T2 problem started right before Aug 31 09:23 lockloss and never go away. DAC recalibration this morning didn't solve the issue and the power glitch didn't cause it. The noisy/glitchy feature looks just like what happened before the drive swap back in Aug 18.
We brought the SR3 to SAFE for a few minutes. The width of the noise still looks the same but the glitches were gone. This implies that the glitches come from the actuator. These glitches don't seems to appear in MASTER_OUT or NOISEMON channels but they do appear in the witness channels. The first plot is the SR3 T2 before we brought it to SAFE, second plot is after SAFE, and the third plot is 15 minutes before 09:23 lockloss.
