[Arnaud, Michael, Jim, Fil, Shoshana]

As mentioned in 90702, one of the readouts for the CRS HoQI amplifier wasn't working, after investigating we figured out that it was an issue with a broken op-amp in a transimpedance amplifier (HoQI B, channel E/COS). Fil switched out the op-amp so we now have a working chassis. Our best guess is that the op-amp failed after plugging it into the rack.

The HoQI on the left side of the CRS (SN01-005, currently HoQI2) had much lower fringe visibility than the other one (SN02-007) since yesterday. We figured out that the laser collimator was positioned in a way where the beam wasn't hitting the center of the photodiodes. The laser collimator was re-aligned and we were able to greatly increase the fringe visibility so the HoQIs now match.

HoQI 1 (SN02-007), SIN: 86.7%, COS: 79.4%, MCOS: 84.9%

HoQI 2 (SN01-005), SIN: 81.4%, COS: 82.7%, MCOS: 80.1%

CRS was balanced, currently has a estimated resonance frequency of 15.7mHz, but we will re-check it in the morning. We are leaving the laser on over night hoping to get some noise measurements, both due to the air currents in the clean room, and the fact that we didn't ground the damping capacitors, it looks unlikely that it will damp down overnight.

Arnaud got the ellipse fitting working, the python script is in /opt/rtcds/userapps/trunk/isi/h1/scripts/write_ellipse_values3.py

We added a gain 0.0847 um/cnt (1064 nm/4pi) to the HoQI Dist filter banks to calibrate the HoQIs into distance. We also changed the CRSRY_PHI_SUM matrix elements to 2.75 to put the RY channels into urad.

An unrelated mystery: HoQI1 and HoQI2 are switched, we aren't sure where in the chain they get flipped, but right now we are guessing it's at one of the cables to the chassis