TITLE: 10/03 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Corrective Maintenance
INCOMING OPERATOR: None
SHIFT SUMMARY: We're still having trouble at TR_CARM. There was some weirdness with PR2 then SRM, I'm leaving IFO in down for the weekend.
LOG:
| Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
|---|---|---|---|---|---|---|
| 00:09 | CDS | Tony, Erik | H2 | N | Front end test setup | 00:34 |
~23:30 UTC While I was locking DRMI to then touch up SRM, after doing the same for PRMI and PRM, all of M3 and M1 LF RT immediately saturated with a huge signal coming from ISC L. Looking at the LSC SRC1 filter bank, we could see that the error signal could not reach positive 800 due to the offset of -800. Keita then turned off FM4 and the saturations stopped, turning it back on brought them right back. We were able to turn that filter off and on while seemingly remaining locked (if it was a real lock, heres a plot of the sidebands power during PRMI then the subsequent DRMI, the levels are about the same) on DRMI 1f despite having no length feedback. The SRM alignment was likely bad, it "held" until I manually brought us down with ISC_LOCK.
