Ed, Sheila, Jenne, Patrick

We locked at 35W this morning following work done last night reported in 47606 and comments.  

• POWER_30W is now going to 35W.
• We measured the PRCL gain at 30W, the ugf was already a bit low, once we powered up to 35W it decreased a bit more so we set the gain to 16 to get a ugf of 45Hz, we could make it higher. 
• We measured the MICH P gain which was not changed from 30W yesterday, so we left the gains of both MICH ASC gains as we had found them yesterday.  
• We found that the POPX centering PZT was railing, which was also happening during last night's 35W lock, Patrick and I relieved it by turning knobs on the steering mirror that points to POPX (near the edge of the table).  It seems likely that there has been some confusion about how to offload this,  the output of the integrator is circled in the attached screenshot, that is what should be driven to zero.  Since the voltage applied to these PZTs goes from 0 to positive voltages, they are at the center of their range when the "MONITOR" is around 16000 counts.  If we adjust the steering so that the "MONITOR" is around 0, we will be near the limits at the output of the integrator, which might be why we were so close with this that a small change in power caused us to rail.  
• Jenne made measurement to re-tune MICH and SRCL FF at 35W.  We turned on the old FF and the coherence is low, so for now we are just continuing to use it. 
• Patrick and I measured the CARM OLG, which was at 15kHz with 6dB IN1 GAIN on the CM servo.  We powered off the Aglient which was connected to the IMC board, but left the SR785 connected to CARM (excitation disabled).  We couldn't find the ethernet cable we used to use for GPIB, so it is not connected to GPIB right now.  
• We thought that the guardian would not increase the gain beyond 6dB in "LASER_NOISE_SUPPRESSION", based on looking at the code, but it set the gain to 9dB, which seemed OK for that lock.  
• We put Georgia's changes for the ISS back into the IMC_LOCK guardian 47607.  We may want to put more thought into how to make the ISS DC coupling work for a variety of laser powers.  

We didn't go to observing, instead PEM injections went ahead, but we tried to do some checks that will make it easier to go into observing soon. 

• We changed the nominal state of the laser power guardian from 30W to 35W.
• Most SDF changes were understood from work over the weekend including the change in input power. 
• MC2 M3 LOCK has a low pass filter engaged, which looking back at the SWSTAT over the last week has been different for an unknown reason between different locks (sometimes FM9 is engaged, sometimes FM10 instead). To be continued...
• The squeezer has a power stabilization servo for the green power, which does not engage if there is too large of an offset.  Daniel engaged this manually by adjusting the offset, but we will need to put some thought into how to run this servo without putting more than 20mW into the squeezer fiber.  To be continued...