J. Kissel, A. Pele, B. Shapiro, J. Warner

In attempts to measure/calibrate the ETMY actuation function from each stage to the arm cavity with high precision (using the Red/Green beat-note when locked on Red), why tried again to get the Green/Red light locked in the arm cavity. However, we failed to get the arm locked. Queue sad trombone -- we lose the end station first thing Monday morning.

Why we think we failed:
- For some reason we couldn't figure out, ISI-ITMY would not isolate at either level 2 or level 3.
    In order to assist long term studies, we decided to isolate to level 2 tonight. ISI-ETMY and ISI-BS came up just fine.
    - Checked that CPS offsets were in the right place
    - Followed the detailed instructions (many times).
    - Trips on bringing up Stage 1 (on the actuators, since we disabled the inertial sensors during the turn on process).
    No dice. Both levels were functional and stable yesterday.

- Poor alignment of the IFO
    - After noodling around with SUS-BS, SUS-PR3, and SUS-TSMY and getting H1:ALS-Y_REFL_B_LF_OUT_DQ no lower than 11000, I realized that, though the ISI-ITMY offsets are small, the table may not be in exactly the right good place I had last night when both ISI-ETMY and ISI-ITMY isolated. After tweaking the ITM alignment, the REFL_B came down to 9000-10000. However, I could not get H1:ALS-C_COMM_A_DEMOD_RFMON to ever go above -29 dBm -- the most I could get was -30 dBm (though this was true last night as well). Further, at some point of the alignment of ITM, I was able to get the REFL_B signal to "bottom out," in that the characteristic 0.4 [Hz] QUAD motion would disappear. So... maybe I'm on the hairy edge of a diode some where?

Where/How it fails: at the end of the CARM_handoff script, and it blows the reference cavity (and subsequently the mode cleaner). 
- During some of the lock losses, the RefCav would take a few minutes to catch lock again, so I thought the IMC Gaurdian was fighting the RefCav, as Stefan / Rick / Kiwamu had diagnosed yesterday. So, I'd switched the IMC Gaurdian to manual for a bit, and the RefCav would come up fine ... but this may just be a red herring.
- Also, I remember Kiwamu / Alexa having trouble with getting past the stage of the CARM_handoff because of the issues with demod phase rotation of the IMC vs. input polarity of the IMC Common Mode Board.


So, we leave the HIFO-Y in a rather sorry state tonight. Note that the red light is still flashing in the arms; I'm not sure what effect this has on the green cavity performance.

Cavities Locked: Input Mode Cleaner, Arm on Green 
Chamber    HEPI                                   ISI                               SUS
HAM1       Locked                                 n/a                               n/a
HAM2       Floating, Alignment Offsets Only       Level 2 Isolated                  MC1, MC3, PRM damped Level 1.5; PR3 damped Level 1.0
HAM3       Floating, Alignment Offsets Only       Level 2 Isolated (eLIGO Blends)   MC2, PR2 damped Level 1.5 
BS         Level 2 Isolated (Position Locked)     Level 2 Isolated                  BS damped Level 2.0
ITMY       Locked                                 Damping Only                      ITMY damped Level 2.1
ETMY       Level 2 Isolated (Position Locked)     Level 2 Isolated                  ETMY damped Level 2.1, TMSY damped Level 2.0


Tonight's BSC-ISI Level 2 is brought to you by:
Blends at ST1 "750mHz" and ST2 "250mHz"
GND to ST1 STS2 Sensor Correction is OFF
ST1 to ST2 T240 Sensor Correction is OFF
ST0 to ST1 HEPI L4C Feed-Forward is ON (with "FF01_2" filters)
The Input Gains for the L4Cs and GS13s are OFF (I *think* this means they're in low -gain mode). They're ON for the T240s.