Lisa, Kiwamu, Stefan

- We had the 18Hz mode of the BS ring up. an additional notch in the MICH loop fixed it.
- We tried to use the REFL27 demod phase to reduce the CARM noise in MICH, but this did not work.
- We had the BS being kicked too hard by the PRMI lock acquisition, producing a yaw misalignment, resulting in a loss of the DIFF beat note. We disabled the BS top mass feed-back, which solved this issue.
- In the process of this debugging we also checked the beat note of DIFF - it was however already pretty well aligned.
- Next we noticed that at -1kHz offset we were sitting right on the 2omega arm resonance. This caused large offset changes in the 3f signal. We decided to try using a ~600Hz offset instead.
- That turned out to make locking on 1f very difficult. 2 hours later we tried a 2kHz offset (on the wrong side of the 1kHz 2f resonance), which worked fine.
- At the 2kHz offset we successfully transitioned to 3f, but as expected, when marching across the 2f arm resonance MICH went unstable.
- But we had to increase the REFLAIR_B_RF27_Q gain in the input matrix from 2.5 to 4.

- Our next goal was to lock at 2kHz offset, then stay on 1f as we move in to about 600Hz, and then try the transition to 3f there.

- another earthquake...