K. Izumi, M. Barton [J. Kissel as moral support and scribe]

    Bolstered by my bold claim of stable H1 IMC locks last night, Mark began launching MC2 violin mode measurements. However, the lock stretches were not long enough to get a full ring-down. My unsubstantiated claim yesterday was air-currents in the PSL were the source of lock losses (see LHO aLOG 7736), but Kiwamu identified it to be low frequency excursions that saturated the MC2's M3 stage drive -- by normal control that should be adequately offloaded to the upper stages of MC2. 
    Why? Two days ago, during Keita's attempt at debugging the IMC (see LHO aLOG 7724), he had modified Stefan's auto-locker (MClockwatch) to use the smaller gains he'd found to be stable. We had forgotten this yesterday, among all the other things wrong. Further, after triple-checking against the known filter configuration (from LLO aLOG 7974), we found FM4 (a [z:p] = [1:100] filter) in the M2 LOCK L bank had been disabled some time during this recent week of guardian commissioning / problem solving (who knows why or by whom, doesn't matter). We've restored the correct gains into MClockwatch, and engaged M2 LOCK L FM4, and the H1 IMC has been locked ever since.

NOW the H1 IMC is back to full awesomeness. MClockwatch is running on opsws5. PSL is still in commissioning mode.

As a reminder, the length loop settings in this configuration are
During Lock Acquisition

H1LSC     H1:IMC-L                = FM1 (antiWhite) * G = +1.0

H1LSC     H1:LSC-MC               = FM10 ( :0.3) * G = +1.0

H1SUSMC2  H1:SUS-MC2_M3_ISCINF_L  = (no filters, G = +1.0)
          
          H1:SUS-MC2_M3_LOCK_L    = FM3 (150:40) * FM9 (CLP300) * G = -300
          
          H1:SUS-MC2_M2_LOCK_L    = FM4 (100:1) * FM10 (ELP70) * G = 0

          H1:SUS-MC2_M1_LOCK_L    = FM2 (0.1.0.01) * G = 0


While Locked:

H1LSC     H1:IMC-L                = FM1 (antiWhite) * G = +1.0

H1LSC     H1:LSC-MC               = (no filters, G = +1.0)

H1SUSMC2  H1:SUS-MC2_M3_ISCINF_L  = (no filters, G = +1.0)
          
          H1:SUS-MC2_M3_LOCK_L    = FM3 (150:40) * FM9 (CLP300) * G = -300
          
          H1:SUS-MC2_M2_LOCK_L    = FM3 (0.1:1) * FM4 (100:1) * FM10 (ELP70) * G = +0.2

          H1:SUS-MC2_M1_LOCK_L    = FM1 (0:0.01) * FM2 (0.1.0.01) * G = +1.0