40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log, Page 31 of 344  Not logged in ELOG logo
ID Datedown Author Type Category Subject Text Attachments
  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.
  
  15803   Thu Feb 11 11:10:05 2021 AnchalSummaryBHDSatellite Amplifier Very Low frequency noise After modificationsHere is a proper measurement for PD transimpedance
amplifier circuit in the Satellite amplifier
box D1002818 S2100029. The input from rear
 AfterChangesSpectrum_AC.zipD1002818_S2100029_OutputNoiseSpecAfterChanges.pdfD1002818_S2100029_InputRefCurrentNoiseSpecAfterChanges.pdfD1002818_S2100029_InputRefDispNoiseSpecAfterChanges.pdf 
  15802   Wed Feb 10 21:14:03 2021 gautamUpdateElectronicsProduction version of the HV coil driver testedSummary:

I did what I consider to be a comprehensive
set of tests on the production version of
 inputDiffRecTF.pdfLVnoises.pdftotalNoise.pdftimeDomainTests.pdf 
  15801   Wed Feb 10 17:18:03 2021 KojiSummaryBHDSatellite Amplifier Output Offset measurementsTesting the satellite amp i.e. 
PD driver
- To test the noise of the PD transimpedance
  
  15800   Wed Feb 10 15:25:45 2021 gautamSummaryBHDSatellite Amplifier Output Offset measurementsWhy not just do this test with the dummy
suspension box and CDS system? I think Rich's
claim was that the intrinsic LED RIN was
  
  15799   Wed Feb 10 15:07:50 2021 AnchalSummaryBHDSatellite Amplifier Output Offset measurementsI measured the output DC voltage of the
satellite amplifier box at PDMon port when
the PDA input was shorted
  
  15798   Wed Feb 10 14:14:58 2021 gautamUpdateElectronicsCustom cables receivedWe received the custom cables to test the
new suspension electronics. They are under
my desk. So we are ready.
 satWiring.pdf 
  15797   Wed Feb 10 11:45:59 2021 AnchalSummaryBHDSatellite Amplifier Very Low frequency noise After modificationsAs suggested, I wrapped the satellite amplifier
box D10028128 S2100029 in blanket and foam
and took very low frequency spectrum starting
 6x 
  15796   Thu Feb 4 15:14:55 2021 YehonathanUpdateBHDSOS assemblyI gathered all the components I could find
from the SOS towers and the cleanroom and
put it all on the table next to the flow
 20210204_144007.jpg 
  15795   Wed Feb 3 21:28:02 2021 gautamUpdateCDSCDS crash and CDS/IFO recoveryI am just reporting my experience - this
may be a new failure mode but I don't
think so. In the new RTCDS, the ntp server
  
  15794   Wed Feb 3 18:53:31 2021 KojiUpdateCDSCDS crash and CDS/IFO recoveryReally!? I didn't reboot the machines
between "sudo date" and "rtcds
start c1x0*". I tried rtcds. If it didn't
  
  15793   Wed Feb 3 16:27:19 2021 AnchalSummaryBHDSatellite Amplifier Transfer Functions and noise After modificationsI have made modifications recommended in
this doc.
The changes made are:
 D1002818_S2100029_TFAfterChanges.pdfD1002818_S2100029_OutputNoiseSpecAfterChanges.pdfD1002818_S2100029_InputRefferedNoiseSpecAfterChanges.pdfD1002812_S2100029_After_Modifications_Feb3.jpgAfterChanges.zip 
  15792   Wed Feb 3 15:24:52 2021 gautamUpdateCDSCDS crash and CDS/IFO recoveryDidn't get a chance to comment during the
meeting - This was almost certainly
a coincidence. I have never had to do
  
  15791   Tue Feb 2 23:29:35 2021 KojiUpdateCDSCDS crash and CDS/IFO recoveryI worked around the racks and the feedthru
flanges this afternoon and evening. This
inevitably crashed c1lsc real-time process.
  
  15790   Tue Feb 2 18:24:54 2021 KojiUpdateBHDSOS assemblyYou can remove the components of the optical
table enclosure (black ones) and use the
optical table as your working area too.
  
  15788   Tue Feb 2 17:09:17 2021 yehonathanUpdateBHDSOS assemblyI set up a working area on the table next
to the south flow bench (see attachment).
I also brought in a rolling table for some
 20210202_165501.jpg20210202_162452.jpg 
  15787   Tue Feb 2 11:57:46 2021 AnchalSummaryBHDHAM-A Coil Driver measurements After modifications TF and Noise S2100028I have made the modifications on the other
board D1100687 S2100028 as well. The measurements
were taken as mentioned in 40m/15784.
 D1100687_S2100028_After_Modifications_Feb01_2021.jpgD1100117_S2100028_TF.pdfD1100117_S2100028_Voltage_Noise_Spectrum.pdfD1100117_S2100028_Current_Noise_Spectrum.pdfAfterChanges.zip 
  15786   Mon Feb 1 12:30:21 2021 gautamUpdateElectronicsMore careful characterizationSummary:


Swapping out the KEPCO
HV supplies (linear) I was using for a pair
 HVPS.pdfHV_testckt.pdftotalNoise.pdf 
  15785   Fri Jan 29 17:57:17 2021 AnchalHowToCDSAcromag wiring investigationI found a
white paper  from Acromag which
discusses how to read differential signal
 GeneralLabWiringDiffWith2Wires.pdfGeneralLabWiringDiffWith3Wires.pdfDiffReadResistorbtwnINandRTN.pdf 
  15784   Fri Jan 29 15:39:30 2021 AnchalSummaryBHDHAM-A Coil Driver measurements After modifications TF and Noise S2100027I fitted zeros and poles in the measured
transfer function of D1100687 S2100027 and
got zeros at 130 Hz and 234 Hz and poles
 D1100687_S2100027_After_Modifications_Jan28.jpgD1100117_S2100027_TF.pdfD1100117_S2100027_Voltage_Noise_Spectrum.pdfD1100117_S2100027_Current_Noise_Spectrum.pdfAfterChanges.zip 
  15783   Thu Jan 28 22:34:21 2021 gautamUpdateSUSDe-whiteningSummary:


We will need de-whitening
filters for the BHD relay optics in order
 DACnoiseModels.pdfactuationRange.pdfdeWhiteTFs.pdfdispNoiseModels.pdf 
  15782   Thu Jan 28 21:44:45 2021 gautamSummaryBHDHAM-A Coil Driver measurements After modificationsLooks fine to me visually but the verdict
can only be made once the z:p locations are quantitatively confirmed,
and the noise tests pass. It would be interesting
  
  15781   Thu Jan 28 18:04:55 2021 AnchalSummaryBHDHAM-A Coil Driver measurements After modificationsI did the recommended
modifications on of the boards with serial
number S2100028. These included:
 D1100117_S2100027_TF.pdfAfterChanges.zip 
  15780   Thu Jan 28 12:53:14 2021 AnchalSummaryBHDHAM-A Coil Driver measurements before modificationsI took some steps to reduce the coupling
of 60 Hz harmonics in noise measurement.
The box was transferred to the floor instead
 D1100117_S2100027_Current_Noise_Spectrum.pdfD1100117_S2100027_Voltage_Noise_Spectrum.pdfD1100117_S2100028_Current_Noise_Spectrum.pdfD1100117_S2100028_Voltage_Noise_Spectrum.pdfSpectrumMeasurement.zip 
  15779   Tue Jan 26 15:37:25 2021 AnchalHowToCDSAcromag wiring investigationHere I present few wiring diagrams when
using Acromag to avoid noisy behavior and
ground loops.
 GeneralLabWiring.pdfGeneralLabWiring2.pdfGeneralLabWiring3.pdf 
  15778   Tue Jan 26 12:59:51 2021 AnchalHowToCDSAcromag wiring investigationTaking inspiration from SR785 on how it
reads differential signal, I figured that
acromag too always need a way to return current
 TestingDifferentialSignalWithFloatingRTNwrtIN-.pdf 
  15777   Tue Jan 26 10:58:30 2021 gautamUpdateSUSMC2 tickler stuck onFor whatever reason, the autolocker didn't
turn the tickle off for several
hours. Seems to work okay now. The linked
  
  15776   Mon Jan 25 18:18:04 2021 AnchalSummaryBHDSatellite Amplifier Transfer Functions and noise 

I took transfer function and noise
measurement of satellite amplifier box's
 D1002818_S2100029_TFandNoiseSpectrum.pdfD1002818_Testing.zip 
  15775   Wed Jan 20 19:12:16 2021 gautamUpdateCDSSLwebview fixedAfter fixing multiple issues, the model
webviews are updating, should be done
by tomorrow. It should be obvious from the
  
  15774   Wed Jan 20 18:07:09 2021 AnchalSummaryBHDHAM-A Coil Driver measurements before modificationsI have taken transfer functions and noise
measurements of the two HAM-A coil driver
boxes D1100687 #S2100027 and #S2100028. All
 7x 
  15773   Wed Jan 20 10:13:06 2021 gautamUpdateElectronicsHV Power supply bypassingSummary:

Installing 10uF bypass capacitors
on the High
 bypassCaps.pdfIMG_9079.jpgIMG_9078.jpgHVampNoise_driven_chassis.pdfprintCoilCurrents.pdf 
  15772   Tue Jan 19 15:43:24 2021 gautamConfigurationCDSUpdated CDS upgrade planNot sure if 1Y1 can accommodate both c1sus2
and c1bhd as well as the various electronics
chassis that will have to be installed. There
  
  15771   Tue Jan 19 14:05:25 2021 JonConfigurationCDSUpdated CDS upgrade planI've produced updated diagrams of the
CDS layout, taking the comments in 15476 into
 40m_CDS_Network_-_Planned.pdf40m_CDS_Network_-_Current.pdf 
ELOG V3.1.3-