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ID Date Author Typedown Category Subject Text Attachments
  4363   Sun Feb 27 13:09:56 2011 ranaUpdateGreen Lockingsidebands on beatnoteWhen Koji and I were massaging the MC,
we noticed that the oscillations were at
48.5 kHz. They were pretty huge and are probably
  
  4365   Tue Mar 1 08:42:18 2011 AidanUpdateelogRestarted the elog this morning The elog was dead this morning.
I reanimated it. It is now undead.
 Zombie.gif 
  4366   Wed Mar 2 04:01:51 2011 KojiUpdateIOOMC servo improvement[Koji / Rana]
- Since the MC servo had UGF up to
~20kHz and huge servo bump at 50kHz, we needed
 IMG_3904.jpgMC_OLTF.pdf 
  4369   Wed Mar 2 18:08:43 2011 AidanUpdateGreen LockingGhost beams on greenKiwamu and I noticed that there is a ghost
beam on the green beam going into the ETM.
What we see is some interference fringes
 Ghost_Beam_at_ETM_DCBS.pdf 
  4370   Wed Mar 2 22:04:22 2011 KevinUpdateElectronicsPOY Shot Noise MeasurementThe previous measurement for the shot noise
of POY had the dark noise at ~100 nV/rtHz.
I redid the measurement and got 26 nV/rtHz
  
  4372   Thu Mar 3 00:12:52 2011 kiwamuUpdateGreen LockingplanTomorrow's tasks
 
- Auto noise budget 
  
  4373   Thu Mar 3 07:25:24 2011 kiwamuUpdateGreen Lockingscrewed up the end PDH box I somehow screwed   
  4374   Thu Mar 3 18:32:33 2011 Larisa ThorneUpdateElectronicsHarmonic distortion calculations for RF distribution boxFinished calculations for harmonic distortion
at each of the 10 outputs of the RF distribution
box. The diagram can be found on Suresh's
 RFdistribboxcalcs.pdf 
  4376   Fri Mar 4 03:31:35 2011 kiwamuUpdateGreen LockingA first noise budgetI made a noise budget for the ALS noise
measurement that I did a week ago (see
#4352).
 noise_budget.png 
  4377   Fri Mar 4 09:47:46 2011 SureshUpdateElectronicsHarmonic distortion calculations for RF distribution box 
Fast work indeed! It would be nice
if we could have the following details filled
  
  4378   Fri Mar 4 13:25:04 2011 ZachUpdateelogrestartedwith script   
  4379   Fri Mar 4 18:06:34 2011 kiwamuUpdateGreen Lockingnoise budget : differential noiseHere I explain how I estimate the contribution
from the differential noise shown in the
plot on my last entry (#4376)
 open_loop_TF.pngservos.png 
  4380   Mon Mar 7 17:22:39 2011 josephbUpdateCDSNew simulated plant work[Joe, Jamie]
We modified the c1scx model to have
a switch to go between simulated and real
  
  4383   Tue Mar 8 06:29:06 2011 kiwamuUpdateGreen LockingIntensity noise setup[Jenne, Chris, Kiwamu]
 A
photo diode and an AOM driver have been newly
  
  4384   Tue Mar 8 14:50:19 2011 kiwamuUpdateCDSnames for filter modules[Joe/Kiwamu]
 
  
  4385   Tue Mar 8 15:20:31 2011 kiwamuUpdateGreen Lockingdifferential noise on Mar.8th   differential_noise20110308.png 
  4386   Tue Mar 8 15:23:16 2011 steveUpdatePEMclean room glovesAnsell
AccuTech
91-300 clean
  
  4388   Tue Mar 8 16:59:47 2011 josephbUpdateCDSSimulated Plant WorkThe screens for the simplified c1spx model
have been updated.  I re-introduced
the suspension point information into the
  
  4389   Wed Mar 9 04:46:13 2011 kiwamuUpdateGreen Lockingmore intensity noise measurement 
Here is a diagram for our intensity
noise coupling measurement.
 intensity_setup.pngIntensityNoise.png 
  4390   Wed Mar 9 16:07:42 2011 kiwamuUpdateVIDEOcable session[Koji, Steve, Suresh, Kiwamu]
The following video cables have been
newly laid down :
  
  4392   Wed Mar 9 18:17:11 2011 kiwamuUpdateGreen LockingIntensity noise couplingHere
is a new plot for the differential noise
measurement. I plot a noise contribution
 diff_noise.pngIN_TF.png 
  4393   Wed Mar 9 23:19:04 2011 kiwamuUpdateCDSrebooted c1iooFor
some reason the c1ioo machine suddenly died
just 30 miteus before.
  
  4395   Thu Mar 10 01:31:37 2011 KevinUpdateElectronicsAS55 CharacterizationsI measured the transfer function, shot
noise, and dark spectrum of AS55.
From the shot noise measurement,
  
  4396   Thu Mar 10 13:44:56 2011 josephbUpdateCDSAdded digitization noise to the c1spy model for simulated ADCs/DACsTo simulate digitization noise, the easiest
way I found was to use the MathFunction block,
found in the CDS_PARTS model, under simLinkParts. 
  
  4397   Thu Mar 10 14:06:54 2011 kiwamuUpdateGreen LockingIntensity noise limits the beatnote sensitivityWe are limited
by the intensity noise of the X arm transmitted
 diff_noise_Mar8.pngIN_TF_complete.png 
  4398   Thu Mar 10 14:22:58 2011 kiwamuUpdateGreen LockingIntensity noise limits the beatnote sensitivityThe next steps we should do are :
    - to investigate
a cause of the intensity fluctuation
         
  
  4399   Thu Mar 10 14:29:05 2011 KojiUpdateGreen LockingIntensity noise limits the beatnote sensitivityWe can modify the freq divider circuit
to make it a comparator.

  
  4400   Thu Mar 10 14:30:53 2011 ranaUpdateGreen LockingIntensity noise limits the beatnote sensitivityThere are 3 standard techniques to
reduce this effect:
1) Stabilize the end laser by sensing
  
  4401   Thu Mar 10 16:00:53 2011 Aidan, JoeUpdateGreen LockingIntensity stabilization loop using beatnote DC.Aidan: Joe and I have added a channel that
takes the DC output from the vertex beatnote
PD and sends it, via RFM, to a DAC at the
 P1000313.jpgP1000314.jpgP1000315.jpgGREEN_ISS_LOOP.pdfScreenshot-C1ALS_OVERVIEW.adl.png 
  4403   Thu Mar 10 21:45:34 2011 ranaUpdateGreen LockingIntensity stabilization loop using beatnote DC.Ridiculous
and hacky. Digital stabilization removed
as well as the old "leave a pile of
  
  4404   Fri Mar 11 11:33:24 2011 josephbUpdateCDSFixed mistake in Matrix of Filter banks naming conventionWhile fixing up some medm screens and getting
spectra of the simulated plant, I realized
that the naming convention for the Matrices
  
  4405   Fri Mar 11 16:30:42 2011 steveUpdateGeneralhigh speed servo unit is hereNew
Focus Servo Controller has just arrived.
We have 25 days to evaluate this product.
 P1070462.JPG 
  4406   Fri Mar 11 18:32:45 2011 josephb, Chris, JamieUpdateCDSDebugging simplant dampingThe FM1 filter module change for XXSEN
was propagated to the ETMX suspension. 
This was a change from a 30,100:3 with a
  
  4408   Sun Mar 13 04:00:53 2011 ranaUpdateCDSETMY Sim workI did some work on the ETMY   
  4409   Sun Mar 13 16:46:48 2011 josephbUpdateCDSETMY Sim work4. The blue Output Filters  section
has been changed to agree with the new filter
of matrices row, column labeling.  My
  
  4410   Fri Mar 18 11:29:36 2011 josephbUpdateCDSMinute trend issues[Joe, Alex]
Steve pointed out to me today he
couldn't get trends for his PEM slow channels
  
  4411   Fri Mar 18 12:22:04 2011 kiwamuUpdateGreen LockingY arm plan for today Prior
to the works on the Y end setup I propose
to perform the temperature scan business
  
  4413   Fri Mar 18 16:06:30 2011 kiwamuUpdateGreen LockingRe: Y arm plan for todayWe use
Alberto's laser for the Y end Green Locking.
  
  4414   Fri Mar 18 16:31:11 2011 Suresh UpdateGreen LockingRe: Y arm plan for todayThe
reason for using Alberto's laser is that
some amount of work has already gone into
  
  4415   Fri Mar 18 17:25:21 2011 josephbUpdateCDSLockins in c1sus update, suspension screens updatedI updated our lockin simulink pieces to
use the newer, more streamlined lockin piece
that is currently in CDS_PARTS (with new
  
  4417   Mon Mar 21 13:26:25 2011 KojiUpdatePSLPMC Trans/RFPDDC PMC TRANS/REFL on MEDM showed red values
for long time.
TRANS (a.k.a C1:PSL-PSL_TRANSPD) was
  
  4418   Mon Mar 21 16:31:02 2011 steveUpdateSAFETYBryan Barr received safety trainingBryan Barr is visiting us from Glasgow
for a month. He received 40m specific safety
training on Friday.
  
  4420   Mon Mar 21 18:34:10 2011 kiwamuUpdateGreen Lockingadded a new ADC channel on 1X9I added a new ADC channel for a DC signal
from the X end green PD.
 aa_board_1X9.jpg 
  4424   Tue Mar 22 16:39:51 2011 kiwamuUpdateGreen Lockingcomaprator installed : 80 pm residual displacement A
comparator has been installed before the
MFDs (mixer-based frequency discriminator)
 noise_curve20110322.png 
  4426   Wed Mar 23 00:51:47 2011 kiwamuUpdateGreen Lockingplan for tomorrow  -
Plan for tomorrow
    * Video cable
  
  4427   Wed Mar 23 05:11:08 2011 kiwamuUpdateGreen Lockingservo handig offSucceeded
in handing off the servo from the green to
 stripTransit_edit.pngnoise_curve20110322_hUGF.png 
  4428   Wed Mar 23 08:50:36 2011 AidanUpdateGreen Lockingservo handig offNicely done!
 

 green-to-red.jpg 
  4429   Wed Mar 23 09:48:20 2011 steveUpdatePSLPSL enclosure: gets new window & laserSolid door, numbered 4 at south west corner
of PSL enclosure was replaced by laser protective
window.
 P1070471.JPG 
  4431   Wed Mar 23 10:34:17 2011 josephbUpdateCDSTrend issue fixed[Joe, Alex]
Yesterday during the day, Alex ran
a script to fix the time stamps in the trends
  
  4434   Wed Mar 23 16:06:20 2011 Larisa ThorneUpdateElectronicsUpdate on cable laying [Steve, Suresh, Larisa]
The following cables were laid today:
ETMYT, ETMY, IFOPO, MC1, OMCR, AS Spare,
  
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