[Sheila, Kiwamu, Terra, Jenne]

• ISS 2nd and 3rd loops simultaneously engaged. No dPdTheta instability tonight.
  • Bug in guardian code prevented this working last night:  wrong value sent to a switch to enable it.  Fixed.
• POP_A offsets tonight seemed to help POP sidebands as well as PRC gain, but still not so good for AS90.  Moving AS_C was delicate, resulted in lockloss.
• CoilDrivers state seems to ring up violin modes drastically.
  • Turned off violin mode damping before transitioning test mass L2 coils worked well.  Didn't turn damping back on, since the modes weren't high. 
  • Kiwamu noticed that the higher order violin mode notches for DARM / ETMs were off in frequency.  He has added notches to fix this.
• Switched to LVLN ETMY ESD. 
• Still need to figure out why CHARD Yaw engagement is so rough - it's better after re-doing the initial alignment setpoints, but it's not great.
• Took data for MICH and SRCL feedforward.
• Can't reshape MICH and SRCL loops as used to be done in Noise_Tunings.  Need to measure loops to understand what's up.

Next up:  Try dither loop to hold ETMX spot position in yaw to prevent spot position movement on BS.  Separate SOFT loops to X and Y, use offset of XSOFT yaw to hold ETMX spot position constant.  Alternatively (or simultaneously), dither BS and demodulate with several different signals at the same time, to understand better how the spot is moving.

We ended up moving PR2 (our uncontrolled recycling optic), and walking it with the POP_A offset.  This allowed us to get to a PRC gain of 31.6 by the O1 standard, but without the sideband powers tanking.  We think that this was promising, and will come back to it tomorrow.  Once we decide that we're happy, we should re-do the green initial alignment setpoints yet again (including the beatnote PDs, which weren't done earlier today) to set this as our reference alignment.  Attached is a big screenshot of where we were most happy.  Also attached is the PR2 offset screen, time-machined back to before we started moving PR2.