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ID Date Author Type Category Subject Text Attachments
  15854   Tue Mar 2 13:39:31 2021 ranaUpdateLSCPRM violin filter excessive?agreed, seems excessive. I always prefer
bandstop over notch in case the eigenfrequency
wanders, but the bandstop could be made to
  
  15853   Mon Mar 1 16:27:17 2021 gautamUpdateLSCPRM violin filter excessive?The PRM violin filter seems very suboptimal
- the gain peaking shows up in the MICH OLTF,
presumably due to the MICH-->PRM LSC output
 violins.pdfPRviolin.pdf 
  15852   Mon Mar 1 12:36:38 2021 gautamSummaryIMCgetting familiar with IMC controlsPretty minor thing - but PMCT and PMCR
were switched on Quad 2 for whatever reason.
I switched them back because I prefer the
  
  15851   Mon Mar 1 11:40:15 2021 Anchal, PacoSummaryIMCgetting familiar with IMC controls[Paco, Anchal]

tl;dr: Done no harm, no
lasting change.
  
  15850   Sun Feb 28 22:53:22 2021 gautamUpdateLSCmore PRMI checks here: what it is ain't exactly clearI looked into this a bit more and crossed
off some of the points Rana listed. In order
to use REFL 55 as a sensor, I had to fix
 PRMI_SBres_REFL55.pngPRMI1f_noArmssensMat.pdfPRMI1f_noArmssensMat.pdfPRMI_locked.pngactTFs.pdf 
  15849   Sun Feb 28 16:59:39 2021 rana, gautamUpdateLSCmore PRMI checks here: what it is ain't exactly clearOn Friday evening we checked out
a few more things, somewhat overlapping with
previous tests. All tests done with PRMI
 RAMestimate.png 
  15848   Sat Feb 27 17:25:42 2021 gautamUpdateElectronicsProduction version of the HV coil driver tested with KEPCO HV suppliesI will try the test of switching out KEPCOs
one at a time for the HP. Given that the
passive RC filter doesn't filter
  
  15847   Fri Feb 26 20:20:43 2021 KojiUpdateElectronicsProduction version of the HV coil driver tested with KEPCO HV suppliesThis is very disappointing. Even with KEPCO
linear supply with the improved HV driver
circuit, the noise level is significantly
  
  15846   Fri Feb 26 16:31:02 2021 gautamUpdateElectronicsProduction version of the HV coil driver tested with KEPCO HV suppliesKoji asked me to test the production version
of the coil driver with the KEPCO HV supplies.
See 
 totalNoise_KEPCO.pdf 
  15845   Thu Feb 25 20:37:49 2021 gautamUpdateGeneralSetting modulation frequency and checking IMC offsetThe Marconi frequency was tuned by looking
at 


The ~3.68 MHz (= 3*f1 -
 modFreq.pdfIMC_offset.pdf 
  15844   Thu Feb 25 16:50:53 2021 gautamUpdateGeneralPRMI sensing matrixAfter all the work at the LSC rack over
the last couple of days, I re-locked the
PRMI (ETMs misaligned), and measured the
 PRMI1f_noArmssensMat.pdf 
  15843   Thu Feb 25 14:30:05 2021 gautamUpdateCDSnew c1bhd setup - diskless bootI've set up one 2U server unit received
from KT in the control room area (the fans
in it are pretty loud but other than
  
  15842   Wed Feb 24 22:13:47 2021 JonUpdateCDSPlanning document for front-end testingI've started writing up a rough testing
sequence for getting the three new front-ends
operational (c1bhd, c1sus2, c1ioo). Since
  
  15841   Wed Feb 24 12:29:18 2021 gautamUpdateGeneralInput pointing recoveredWhile working at the LSC rack, I lost the
input pointing into the IFO (the TT wiring
situation is apparently very fragile, and
  
  15840   Wed Feb 24 12:11:08 2021 gautamUpdateGeneralDemod char part 3I did the characterization discussed at
the meeting today.


RF signal at 100 Hz offset
 noPreamp.pdfwithPreamp.pdfnoPreamp_whitened.pdfwithPreamp_whitened.pdf 
  15839   Wed Feb 24 11:53:24 2021 gautamUpdateGeneralDemod char part 2I measured the noise of the I/F outputs
of all the LSC demodulators. I made the measurement
in two conditions, one with the RF input
 noises_noPreamp.pdfnoises_withPreamp.pdf 
  15838   Wed Feb 24 10:23:03 2021 YehonathanUpdateSUSOSEM testing for SOSsContinuing with the new rig, I measure
the resistance of the cable leading to the
coil to be 0.08+(0.52-0.08)+(0.48-0.08)=0.9ohm.
 OSEM_078_LED_Spot.JPGOSEM_280_LED_Spot.JPGOSEM_117_LED_Spot.JPG 
  15837   Wed Feb 24 10:09:16 2021 yehonathanUpdateSUSOSEM testing for SOSsYes, my phone camera mirrored the image.
Sorry for the confusion.

I see you already uploaded the
  
  15836   Tue Feb 23 23:12:37 2021 KojiSummarySUSSUS invacuum wiringThis is my current understanding
of the in-vacuum wiring:
1. Facts
 SOS_OSEM_cabling.pdf 
  15835   Tue Feb 23 20:55:19 2021 KojiUpdateSUSOSEM testing for SOSsI can't obtain a consistent view between
the existing drawings/photographs and your
pin assignment. Please review the pin assignment
 SOS_OSEM.pdf 
  15834   Tue Feb 23 00:10:05 2021 gautamUpdateGeneralDemod char part 1I measured the conversion efficiencies
for all the RFPD demod boards except the
POP port ones. An RF source was used to drive
 noPreamp.pdfwithPreamp.pdf 
  15833   Mon Feb 22 14:53:47 2021 gautamUpdateCDSdtt-ezca-tools installed on rossaThe defaults cds-crtools didn't come
with some of the older ezcautils (like ezcaread,
ezcawrite etc). This is now packaged for
  
  15832   Mon Feb 22 14:06:49 2021 YehonathanUpdateSUSOSEM testing for SOSsContinuing with the OSEM testing. I measure
the resistance of the wires from the RLC
meter to the coil to be ~ 0.9ohm. I will
  
  15831   Sun Feb 21 20:51:21 2021 ranaUpdateGeneralHousekeeping + PRMI charI'm curious to see if the demod phase
for MICH in REFL & AS chamges between
thi simple Mcihelson and PRMI. IF there's
  
  15830   Sat Feb 20 16:46:17 2021 KojiSummaryElectronicsA bunch of electronics receivedWe received currently available sets. We
are supposed to receive more coil drivers
and sat amps, etc. But they are not ready
  
  15829   Sat Feb 20 16:20:33 2021 gautamUpdateGeneralHousekeeping + PRMI charIn prep to try some of these
debugging steps, I did the following.


ndscope updated from 0.7.9 to
 IPPOSdeat.pdfTTdrift.pdfPOXnPOY.pdfPRMI.pdf 
  15828   Sat Feb 20 10:01:48 2021 gautamSummaryElectronicsA bunch of electronics receivedWill we also be receiving the additional
34 Satellite Amplifier PCBs?
  
  15827   Fri Feb 19 18:22:42 2021 ranaUpdateLSCPRFPMI sensiing matrix woesI would:


look at the free swingin
michelson. Should be able tu null that siggnal
  
  15826   Fri Feb 19 16:55:26 2021 KojiUpdateSUSCoM Range on 3"->2" Adapter Ring for SOSJordan's screenshot actually shows
that the vertical distance (Y) is 0.0000".
We want to have the vertical distance of
  
  15825   Fri Feb 19 16:14:16 2021 gautamUpdateSUSCoM Range on 3"->2" Adapter Ring for SOSI briefly talked with Jordan about this.
This suspension will have OSEMs right? With
400ohm series resistance for the coil drivers,
  
  15824   Fri Feb 19 16:06:01 2021 KojiUpdateSUSCoM Range on 3"->2" Adapter Ring for SOSWe want to move the CoM with the adjustment
range so that the residual deviation is adjusted
by the bottom dumbbell. 0.0003" is well
  
  15823   Fri Feb 19 15:17:51 2021 JordanUpdateSUSCoM Range on 3"->2" Adapter Ring for SOSAdjusting the thickness of the cylindrical
hole for the mirror on the 2" optic
sleeve, from .6875" to .61" thick,
 Neutral_Point.pngDumbell_Max_Negative_Travel.pngDumbell_Max_Positive_Travel.png 
  15822   Fri Feb 19 13:38:26 2021 gautamUpdateLSCPRFPMII forgot that I had already done some investigation
into recovering the PRFPMI lock after my
work on the RF source. I don't really
  
  15821   Fri Feb 19 12:21:04 2021 YehonathanUpdateBHDSOS assemblyA summary of things that need to be fabricated/purchased/done:




  
  15820   Thu Feb 18 20:24:48 2021 KojiSummaryElectronicsA bunch of electronics receivedTodd provided us a bunch of electronics.
I went to Downs to pick them up this afternoon
and checked the contents in the box. Basically,
 IMG_0416.jpeg 
  15819   Thu Feb 18 20:20:25 2021 KojiUpdateSUSaLIGO Sat Amp characterizationYeah, it's really inconsistent. You
had 35mA LED drive and the current noise
of the noisy channel was 5e-7 A/rtHz at 1Hz.
  
  15818   Thu Feb 18 18:05:04 2021 gautamUpdateSUSaLIGO Sat Amp characterizationBefore installation, I performed a bunch
of tests on the aLIGO sat amp. All the measurements
were made with the dummy suspension box substituting
 OSEMnoise.pdfLEDdriveNoise.pdf 
  15817   Thu Feb 18 15:33:21 2021 gautamUpdateSUSaLIGO Sat Amp installed, powered and commissionedThe WFS servo was recommissioned. The matrix
can be tuned a bit more, but for now, I've
recovered the old performance and the alignment
  
  15816   Thu Feb 18 15:15:12 2021 yehonathanUpdateSUSOSEM testing for SOSsI am setting up a testing rig for the OSEMs
we recently obtained. I found the schematic
for the OSEM assembly from which the pin
 OSEM_Pin_Plate.png 
  15815   Thu Feb 18 03:20:09 2021 KojiSummaryElectronicsCurrent Rack MapFor your planning:  rack_plan.pdf 
  15814   Wed Feb 17 16:11:53 2021 gautamUpdateSUSaLIGO Sat Amp installed, poweredThere is some non-trivial sign flipping
in the sensors/coils in this new setup because
it is a hybrid one with the old interfacing
  
  15813   Wed Feb 17 13:59:43 2021 KojiUpdateSUSCoM on 3"->2" Adapter Ring for SOSNote from today's meeting:

1. Can we adjust the thickness of
  
  15812   Wed Feb 17 13:59:35 2021 gautamUpdateDetCharSummary pagesThe summary pages had failed because of
a conda env change. We are dependent on detchar's
  
  15811   Tue Feb 16 22:59:36 2021 YehonathanUpdateBHDSOS assemblyDone.

Also, the magnets are nickel-plated.
I guess that doesn't matter for the baking
  
  15810   Tue Feb 16 15:29:01 2021 KojiUpdateBHDSOS assemblyThe curie temp of SmCo seems about x2 (in
K) of the one for NdFeB. i.e. 600K vs 1000K.
So I believe 177degC = 450K is not an issue.
  
  15809   Tue Feb 16 14:56:44 2021 gautamUpdateSUSaLIGO Sat Amp installed, powered[jordan,
gautam]


Ran 60ft long cables from
 MC1_deadUL.pngIMG_9100.jpg 
  15808   Tue Feb 16 13:13:39 2021 YehonathanUpdateBHDSOS assemblyGautam pointed out that there are extra
Sm-Co magnets stored in the clean optics
cabinet.
  
  15806   Fri Feb 12 15:03:48 2021 JordanUpdateSUSCoM on 3"->2" Adapter Ring for SOSAs it currently stands the Center of Mass
of the Adapter Ring/Optic assembly is 0.0175"
out of the plane formed by the suspension
 Screenshot_(1).pngScreenshot_(3).pngCoM.PNG 
  15805   Thu Feb 11 18:21:39 2021 gautamUpdateSUSMC suspension glitchesMC1
suspension is glitching again, so
this is a good chance to install the new
  
  15804   Thu Feb 11 16:58:52 2021 ranaSummaryBHDSatellite Amplifier Very Low frequency noise After modificationsI expect that a single OSEM channel can't
be better than 1e-10 m/rHz above 5 Hz, so
probably something wrong in the calibration.
  
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