Elli, Thomas, Stefan

- We found that the DRMI build-up fluctuations reported in alog 15765 were mostly due to a small offset in the WFS locking point for the SRC (feed back to SRM yesterday, switched to SR3 today).
- We fine-tweaked the input matrix mixing signals from AS36 A (orthogonal to the BS signal) and AS36 B (I&Q), such that we maximize the SR3 signal and get a good locking-point offset.
  The matrix is:
    AS A RF36I -0.45
    AS A RF36Q  0.89
    AS B RF36I  1.1
    AS B RF36Q -0.77
  This was found for pitch. Yaw was confirmed to be close, but wind prevented further fine-tuning. Using this significantly reduced the build-up fluctuations.

- Next we commissioned the a high BW loop for SR3. The filters are
    PIT: zpk([0.06+i*0.815;0.06-i*0.815;0.3+i*3.25;0.3-i*3.25],[0.3+i*2.87;0.3-i*2.87;11.1111+i*38.4258;11.1111-i*38.4258],1,"n")
    YAW: zpk([0.13+i*1.24;0.13-i*1.24;0.15+i*2.88;0.15-i*2.88],[0.15+i*2.48;0.15-i*2.48;11.1111+i*38.4258;11.1111-i*38.4258],1,"n")
  They were successfully tested up to a UGF of 6Hz using an optical lever. However, on the WFS we could not go that high because there was significant cross-talk from the other loops.
  Thomas will attach a measured transfer function.

- We left the feed-back on SR3 (the guardian sets this up), but with maybe 10 times lower BW.

- We also noticed that the high BW WFS cause more violent lock losses. We thus put (generous) limiters to all the top stages.

Unfortunately the winds are at 60mph again, so we won't leave it locked tonight.