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ID Date Author Type Categorydown Subject
  165   Tue Sep 3 17:03:25 2013 KojiGeneralGeneralH1 OMC gluing completed

[Koji Jeff]

H1 OMC All Gluing completed

5 Glue H1 beam dumps (UV)

4 glass wire brackets glued on the H1 topside (UV) SN: #9/10/11/12

6 Invar blocks glued on the H1 topside (EP30) SN: #13/14/15/16/18/19

  166   Wed Sep 4 22:22:54 2013 KojiGeneralGeneralH1 OMC wrapped and moved to the bake lab.

[Koji, Jeff]

We moved the H1OMC to the bake lab.

Chub set up the vacuum bake oven (Oven F) and running without the actual OMC.

We use low temperature (55degC) for the baking.

The actual OMC will be baked from tomorrow afternooon.

  167   Sat Sep 7 17:20:56 2013 KojiGeneralGeneralOMC/PD lab optical table wrapping

[Koji Jeff]

In order to prepare for the splinkler installation on the HEPA enclosure, the table with the optics was wrapped with Ameristat sheets.

Attachment 1: P9064377.JPG
P9064377.JPG
  168   Fri Sep 13 15:09:20 2013 KojiGeneralGeneralSprinkler installation: done

A sprinkler head was installed on the HEPA enclosure. The head is covered with a plastic cap.

Attachment 1: P9134379.jpg
P9134379.jpg
Attachment 2: P9134378.jpg
P9134378.jpg
  173   Tue Oct 22 17:17:59 2013 KojiGeneralGeneralH1OMC cabling

[Chub, Jeff, Koji]

We worked on the wiring and routing of the cables.

- The cables for the PZT was installed first.

- Pins for the mighty mouse connector were crimped on the PZT wires

- Checked the wiring diagram (D1300589) to find the pinouts.
  Pin1 of the mighty mouse is connected to PZT2+, Pin2 to PZT2-, PIn3 to PZT1+, and Pin4 to PZT1-

- Then QPD and PD cables are fixed on the cable harness.

- The QPD/PD cables are attached on the diode housings.

During this process one of the DCPD mounts moved. The fixing screws were not torqued enough.
This means that all of the FC layers need to be removed and the DCPD housing should be aligned again.

- We continued on the cabling. The cables were routed on the top (cable) side.

- Some of the cable pegs were tightened by PEEK cable ties.

- We found that Pin1 and Pin2 of the PZT cables were not intact anymore.

- We ask Chub to work on the PZT pins tomorrow. The PD alignment will be taken tonight or tomorrow.

  174   Wed Oct 23 02:45:07 2013 KojiGeneralGeneralPD realignment

DCPD2 got misaligned during the cable installation. The PD alignment procedure have been gone through again.

Cavity locking

- Removed the FC layers for the cavity related mirrors.

- Aligned and locked the cavity.

PD alignment

- Loosen DCPD2. Checked the reflection with a IR card. Checked the spot on the PD with an IR viewer.

- Finger-tight the screws. Check the reflection with the card again. Check the pot on the PD with a CCD.

- If the spot positions are not satisfactory repeat the process.

- If the spot positions are satisfactory, take pictures of the CCD image.

- Fixing screws for all of the PDs/QPDs were tighten by the torque driver with a torque od 1.75 inch lb.

PD QE measurements

- Measure the power incident on the PDs.

- Set up the transimpedance amp to check the photo current.

- PD1 (T side) 9.10+/-0.03 V 13.02 +/- 0.01W -> QE ~80%

- PD2 (R side) 8.70+/-0.01 V 12.53 +/- 0.01W -> QE ~80%

- These are not strange values considering the presence of the glass caps.

PZT polarity check

- The connections between the PZT electrodes and the pins were checked.

- The positive side is marked by a knot on the wire.

FC painting

- The new FC bottle was brought from Downs, thanks to Margot.

 

  175   Mon Nov 4 19:43:56 2013 KojiGeneralGeneralH1OMC Packed

H1OMC PZT connector was replaced with the correct one. This was the final step for H1OMC.

Jeff and I packed the OMC and put it in the perikan case. It will be shipped tomorrow.

The other tools are also packed in the other box. Here is the list of the items

- Spare PD/QPDs (2 cages)
- Test PD/QPD cables
- Torque driver / bits
- Low noise transimpedance amp
- Kapton sheets
- First Contact kit
- 1/4-20 Screws for the balance weights
- OMC-Structure cables
- Preamp adapter plate
- Screws for the cable mounts
- Clean tools
  (scissors, tweezers, forceps, Diagonal pliers, long nose prier)
- Spare Peek cable ties
  176   Thu Nov 21 00:05:35 2013 KojiGeneralGeneralH1OMC electronics arrangement

Checked the PZT arrangement: Mighty Mouse Pin1&2 -> PZT2 (DCPD side), Mighty Mouse Pin3&4 -> PZT1 (QPD side)

DCPD response:
Illuminate DCPD1 (T) -> DCPD B responded in MEDM
Illuminate DCPD2 (R) -> DCPD A responded in MEDM

QPD response:
Illuminate QPD1 -> QPD A responded in MEDM
Illuminate QPD2 -> QPD B responded in MEDM

--------

DCPD1 (T) is marked as "A". This PD is SN"0288"

DCPD2 (R) is marked as "B". This PD is SN"0721"

Corresponding iLOG for the performance

Attachment 1: H1OMC_cable_arrangement.pdf
H1OMC_cable_arrangement.pdf
  177   Tue Dec 10 16:41:51 2013 KojiGeneralGeneralTo Buy

Masks / Wipes => done

  178   Tue Feb 18 18:58:38 2014 KojiGeneralGeneralLHO H1 OMC installation photos

LHO OMC installation photos

  179   Fri Feb 28 19:50:11 2014 KojiGeneralGeneralMisalignment ABCD matrix for the aLIGO OMC

Relationship between mirror misalignment and cavity mode shift was calculated.
The technique described in T0900647 by Sam Waldman was used.

The angles and displacement of the mirrors and beams are defined in the attached figure.

x1 = 0.893134 α + 1.10676 β + 1.32252 γ + 1.24619 δ
𝛳1 = 0.75864 α - 0.75864 β - 0.271075 γ + 0.271075 δ

x2 = 1.10676 α + 0.893134 β + 1.24619 γ + 1.32252 δ
𝛳2 = 0.75864 α + 1.24136 β - 0.271075 γ + 0.271075 δ

x3 = 1.32252 α + 1.24619 β + 1.1691 γ + 1.39962 δ
𝛳3 = -0.271075 α + 0.271075 β + 0.818668 γ - 0.818668 δ

x4 = 1.24619 α + 1.32252 β + 1.39962 γ + 1.1691 δ
𝛳4 = -1.24136 α - 0.75864 β - 0.271075 γ + 0.271075 δ

Assuming the flat mirrors are fixed:
If I want to move the x3 mirror up by 1mm without moving x4, the solution is
γ = -0.00197 mrad
δ = +0.00236 mrad

This yields:
x1 = +0.33mm, x2=+0.66mm, x3 = +1mm, x4 = 0mm

Attachment 1: misalignment.pdf
misalignment.pdf
  182   Thu Apr 17 21:39:25 2014 KojiOpticsGeneralMore alignment

STORY:

- The cavity mirrors have scattering spots. The cavity alignment should have been scanned to find a cavity mode to have lowest loss possible.
  BTW, We only have horizontal dof for the alignment scan.

- After some struggle nice cavity mode was found. The cavity transmission was 96% for the ideally matched TEM00 carrier.

- It turned out that this imposed too much beam shift in the input beam (~2mm).

- This big shift induces a lot of trouble for the peripheral optics (PDs, QPDs, sterring mirrors).

- What should we do???

Analysis:

- The beam needed to go up between CM1 and CM2 to have the right spots on them. ("UP" is the input side of the OMC).

- This imposed the beam between FM1 and FM2 moved up. In other word, for the given alignment of the FMs by the template,
  We needed to hit the upper part of the FMs to have the spots on the CMs up.

Solution:

- The above argument suggets that the nominal beam will give us the right spots on the CMs if we rotate the FMs.
  Of course this induces the spot move on the FMs. But this should not be the issue as the most of the loss seems to come from the CMs.

- How much misalignment show we give to the FMs? We want to shift the beam by 2mm on the CMs.
  The length of the optical lever is ~0.25m. Therefore the mialignment angle should be

  theta = 2e-3/2/0.25 = 4e-3 rad = 4mrad.

  The template pad has ~20mm separation. The thickness of the shim should be 20mm*4mrad = 80um

- Our aluminum foil seems to have the thickness of 30-40um. We can't have this minimum thickness on the template pad as there is not enough compression pressure
  => Just use a single layer of Al piece to shim the FMs.

Attempt:

- The shims were inserted at the upper pads of the FMs.

- Aligned the input beam and the CMs so that the spots on the CMs are approximately recovered.

- Measure the cavity power budget

Pin: 34.7mW
Refl PD: offset = -7.5mV, unlock = 6.07V, inlock = 89.7mV

Ptrans = 32.5mW

Ptrans(CM2) = 0.181mW
Ptrans(CM2) = 0.184mW

Assume finesse of 400

==>

Pin: 34.7mW
Pjunk: 0.534mW
Pcoupled: 34.1mW

Mode matching: 98.5%

Cavity reflectivity in power: 0.00061
Cavity transmission in power: 0.951 (This is not a best number but acceptable.)
Loss per mirror: 75.4ppm

FM power refl/trans: 0.9923 / 7630ppm
CM1 power refl/trans: 0.999882 / 42.8ppm
CM2 power refl/trans: 0.999881 / 43.5ppm
Total roundtrip loss of the cavity (Loss + CM leakage): 388ppm

Result:

How much the input beam is away from the left wall of the OMC breadboard?

40.88mm from the template edge
  8.36mm between the template edge and the bread board
=> 32.52mm

How much should this number be? 32.94mm from the solidworks model => With in 0.5mm! Nice!

Next:

- Just in case plce all of the optics and check if the beam is delivered within the alignment range of the optics

 

  187   Thu Jun 19 23:16:50 2014 KojiOpticsGeneralAll of the prisms have been glued

- All of the PRISM mirrors have been glued

- 4 out of 5 beam dumps have been glued


TODO

EP30-2 gluing of the INVAR blocks for the PDs

PDs/QPDs need to be slightly lower -> order more shims

Remove the templates

Glue the last beam dump

Vibration test?

Bring the OMC to the bake lab

Vacuum baking

Bring it back to the OMC lab

Cabling / Wiring

Optical tests

Backscattering test

Packing / Shipping

P6196525.JPG

  188   Fri Jun 20 18:59:12 2014 KojiOpticsGeneralAll of the invar blocks have been glued

All of the INVAR blocks have been glued.

I found thinner shims in the stock.

On Monday, the template will be removed.

EP30-2 7g mixed with 0.35g of 75-90um sphere


TODO

EP30-2 gluing of the INVAR blocks for the PDs

PDs/QPDs need to be slightly lower -> order more shims

Remove the templates

Glue the last beam dump

Vibration test?

Bring the OMC to the bake lab

Vacuum baking

Bring it back to the OMC lab

Cabling / Wiring

Optical tests

Backscattering test

Packing / Shipping

  189   Mon Jun 23 21:54:16 2014 KojiOpticsGeneralAll of the gluing completed

The bottom-side templates were removed.

The last beam dump was removed

TODO

ICS entry

Bring the OMC to the bake lab

Vacuum baking

Bring it back to the OMC lab

Cabling / Wiring

VIbratin test

Optical tests

Backscattering test

Packing / Shipping

 

  190   Tue Jun 24 18:43:15 2014 KojiGeneralGeneralICS entries for the OMC baking/assembly

For baking:

  • Assembly Name aLIGO Output Mode Cleaner
    Assembly Number D1201439
     
  • Part Name: Breadboard transport fixture
    Part # / Drawing #: D1201515
     

TO BE ADDED TO THE ASSEMBLY after the bake: [DONE]
803-003-07M6-4PN-598A-0-Bulk-H42Q001
D1201274-V1-00-S009: OMC DCPD Housing        (remove part)
D1201274-V1-00-S010: OMC DCPD Housing        (remove part)
D1201275-V1-00-0006: OMC DCPD FACE PLATE        (remove part)
D1201275-V1-00-0007: OMC DCPD FACE PLATE        (remove part)
D1201280-V1-00-0006: OMC QPD HOUSING        (remove part)
D1201280-V1-00-0007: OMC QPD HOUSING        (remove part)
D1201281-V1-00-0006: OMC QPD FACE PLATE        (remove part)
D1201281-V1-00-0007: OMC QPD FACE PLATE        (remove part)
D1300052-V1-00-0003: aLIGO OMC BRACKET, CABLE CONNECTOR        (remove part)
D1300057-v2-00-0021: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0022: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0023: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0024: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0025: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0026: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0027: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0028: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0029: aLIGO CABLE PEG        (remove part)
D1300057-v2-00-0030: aLIGO CABLE PEG        (remove part)
D1300060-V1-00-0005: aLIGO OMC BRACKET, MASS MOUNTING        (remove part)
D1300060-V1-00-0006: aLIGO OMC BRACKET, MASS MOUNTING        (remove part)


====================================
More entries to be added (Found in the LHO OMC entry) [DONE]
D1300371-V2-00-S1301806: ISC DCPD Cable for OMC-Breadboard Bracket to DCPD #1
D1300372-V2-00-S1301807: ISC DCPD Cable for OMC-Breadboard Bracket to DCPD #2
D1300373-V3-00-S1301810: ISC QPD Cable for OMC-Structure to Breadboard Bracket
D1300374-V2-00-S1301813: ISC QPD Cable for OMC-Breadboard Bracket to QPD #1

  191   Fri Jun 27 12:29:50 2014 KojiGeneralGeneralOMC baking

The OMC went into the oven at around 2PM on Thursday. It will be baked at 80degC for 48 hours.
The RGA result will be obtained on Monday.

Link to the ICS entry

P6266536.jpg

  192   Fri Jun 27 18:51:33 2014 KojiGeneralGeneralSupply

PTOUCH TAPE (12mm white) x 2

9V batteries

  193   Wed Jul 2 16:41:43 2014 KojiGeneralGeneralOMC baking

OMC is back from the oven today.

To Do:

Optical tests

  • Cleaning
  • Power Budget
  • FSR measurement
  • TMS measurement
  • TMS measurement (with DC voltage on PZTs)
  • PZT DC response
  • PZT AC response
  • QPD alignment
  • DCPD alignment
  • First Contact

Backscattering test

Cabling / Wiring

  • Attaching cable/mass platforms
  • PZT cabling
  • DCPD cabling
  • QPD cabling

Vibration test

Packing / Shipping

  194   Wed Jul 2 18:58:42 2014 KojiGeneralGeneralBeam dump delamination

While the OMC breadboard was being inspected, it was found that two out of five black-glass beam dumps showed sign of delamination.
(attached photos).

The base of the each beam dump is a fused silica disk (25mm dia.). The black glass pieces are bonded to the disk. The bond is EP30-2
epoxy without glass beads for bond lining. The disk is bonded on the fused silica bread board with Optocast UV low-viscous epoxy.
The delamination is about 70% of the bonded area. They don't seem to fall off immediately. But the glass pieces are not completely secure.
(i.e. finger touch can change the newton ring fringes) So there might be some risk of falling off during transportation.

The engineering team and I are exploring the way to secure them in-situ, including the method to apply UV epoxy with capillary action.

Attachment 1: beamdump_delamination.png
beamdump_delamination.png
  195   Thu Jul 3 17:45:18 2014 KojiGeneralGeneralBeam dump delamination

Here is the resolution.

I'll apply fillets of EP30-2 along the edges of the black glass (See figure).
In order to allow the air escape from the gap, the inside of the V will not be painted.
In any case, I don't have a good access to the interior of the V.

Dennis assured that the outgassing level will be ok even if the EP30-2 is cured at the room temp if the mixture is good.
But just in case, we should run an RGA scan (after 50degC for 24hour vac bake).
I prefer to do this RGA scan right after all of the test and cabling and right before the shipment.
Dennis is checking if we can even waive the RGA scan owing to the small volume of the glue.

beamdump_delamination_solution.png

  196   Sun Jul 6 02:45:56 2014 KojiOpticsGeneralFSR Measurement

3rd OMC FSR / Finesse measurement

RF AM was injected by detuning a HWP.

Attachment 1: finesse_measurements_log.pdf
finesse_measurements_log.pdf
  200   Mon Jul 7 01:36:03 2014 KojiGeneralGeneralTo Do

Optical tests

  • Cleaning
  • Power Budget
  • FSR measurement
  • TMS measurement
  • TMS measurement (with DC voltage on PZTs)
  • PZT DC response
  • PZT AC response
  • QPD alignment
  • DCPD alignment

Backscattering test

Cabling / Wiring

  • Attaching cable/mass platforms
  • PZT cabling
  • DCPD cabling
  • QPD cabling

Vibration test

Baking

First Contact

Packing / Shipping

  201   Tue Jul 8 04:08:06 2014 KojiGeneralGeneralExpoxy reapplication for beam dumps

Firstly, the excess epoxy was removed using a cleaned razor balde

Secondly, EP30-2 epoxy was applied at the exterior edges of the beam dump.
Interior of the V were glued at two points. This is to keep the gap away from being trapped

Here is the result of the gluing. Some epoxy was sucked into the gap by capillary action.
I believe, most of the rigidity is proivded by the bonds at the edges.

  203   Thu Jul 10 01:39:38 2014 KojiElectronicsGeneralPZT wire

Rich came to the OMC lab. Pins for the mighty mouse connector were crimped on the 4 PZT wires.
We found the male 4pin mighty mouse connector in the C&B area.

The cable inventory was checked with ICS/DCC combo. It turned out that most of the on-board cables
are at LHO. We decided to send the OMC there and then the cables are installed at the site.

Attachment 1: P7096669.JPG
P7096669.JPG
  204   Thu Jul 10 08:34:57 2014 KojiGeneralGeneralTo Do

Optical tests

  • Cleaning
  • Power Budget
  • FSR measurement
  • TMS measurement
  • TMS measurement (with DC voltage on PZTs)
  • PZT DC response
  • PZT AC response
  • QPD alignment
  • DCPD alignment

Backscattering test

Cabling / Wiring

  • Attaching cable/mass platforms
  • PZT cabling
  • DCPD cabling (to be done at LHO)
  • QPD cabling (to be done at LHO)

Vibration test

Baking

First Contact

Packing / Shipping

  212   Sun Jul 20 17:20:39 2014 KojiGeneralGeneralThe 3rd (LIO) OMC was shipped out to LHO

The 3rd (LIO) OMC was shipped out to LHO on Friday (Jul 18) Morning.

At LHO

- All of the on-breadboard cables should be attached and tied down.

- Peel First Contact paint and pack the OMC for storage.

 

  214   Thu Jul 31 15:07:53 2014 KojiGeneralGeneralItem lending

Tara: Laser Safety goggle -> Returned

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

  215   Mon Aug 4 18:59:50 2014 KojiGeneralGeneralA memorandom

On breadboarfd cabling for 3IFO OMC

D1300371 - S1301806
D1300372 - S1301808
D1300374 - S1301813
D1300375 - S1301815

  216   Tue Aug 5 13:03:25 2014 KojiGeneralGeneralMissing cable components

DCPD Connector Face: Qty2 https://dcc.ligo.org/LIGO-D1201276
QPD Connector Face: Qty2 https://dcc.ligo.org/LIGO-D1201282

PD faster: 92210A07 Qty 4: MCMASTER #2-56 x .25 FHCS

Spare DCPD

  219   Sat Jan 17 11:40:04 2015 KojiGeneralGeneral3rd OMC completed

Jan 15, 2015 3rd OMC completed

The face caps of the DCPD/QPD cables were installed (Helicoils inserted)
PD7&10 swapped with PD11(for DCPD T) and PD12(DCPD R).
Firct Contact coating removed

Note on the 3rd OMC

Before the 3rdOMC is actually used,

- First Contact should be applied again for preventing contamination during the installation

- DCPD glass windows should be removed

  220   Fri Jan 30 19:31:08 2015 KojiGeneralGeneralItem lending

Gabriele:

PZT HV Amp

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)Returned March 23, 2016
Black glass beam dump

Dmass:

LB1005 Oct 24. This unit is permanently gone to Cryo lab. Acquired a new unit. Aug, 2016.

Quote:

Tara: Laser Safety goggle -> Returned

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

 

  221   Tue Feb 3 18:23:49 2015 KojiGeneralGeneralItem lending

- The laser was removed and shipped to LHO today.

- UV illuminator / fused silica fiber light guide / UV power meter / UV face shield (Qty 2) will be shipped to MIT.
They are CIT properties except for the illuminator.

Quote:

Gabriele:

PZT HV Amp

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

Quote:

Tara: Laser Safety goggle -> Returned

Evan:
HP signal generator (990MHz) (prev. setting 32.7MHz / +3dBm)
Black glass beam dump

Dmass:

LB1005 Oct 24.

 

 

  222   Wed Feb 4 20:07:24 2015 KojiGeneralGeneralItem lending

Shipment to MIT (L. Barsotti, J. Miller)

1. UV Illuminator (LESCO Super Spot MK III)

2. UV Power meter (American Ultraviolet AIB1001) Caltech property C30140

3. UV protection face shield (VWR UVC-803) Qty.2 Caltech property C30141/C30142

4. UV Fiber Optic Light Guide (American Ultraviolet OLB1081) C30143

All returned: Aug 30, 2016

Attachment 1: C30140_1.JPG
C30140_1.JPG
Attachment 2: C30140_2.JPG
C30140_2.JPG
Attachment 3: C30141.JPG
C30141.JPG
Attachment 4: C30142.JPG
C30142.JPG
Attachment 5: C30143.JPG
C30143.JPG
  223   Wed Feb 18 21:51:23 2015 KojiGeneralGeneralNotes on OMC Transportation Fixtures & Pelican

LLO has one empty OMC transportation fixture.

LHO has one empty OMC transportation fixture.

LHO has one OMC transportation fixture with 3IFO OMC in it.

LHO has the Pelican trunk for the OMC transportation. Last time it was in the lab next to the optics lab.

  226   Tue Jul 21 20:20:12 2015 KojiGeneralGeneralItem lending

Kate (ATF)

- 4ch color oscilloscope (Tektronix)

- Chopper controller

- Chopper with a rotating disk

  235   Thu Aug 20 01:35:01 2015 KojiElectronicsGeneralOMC DCPD in-vacuum electronics chain test

We wanted to know the  transimpedance of the OMC DCPD at high frequency (1M~10M).
For this purpose, the OMC DCPD chain was built at the 40m. The measurement setup is shown in Attachment 1.

- As the preamp box has the differential output (pin1 and pin6 of the last DB9), pomona clips were used to measure the transfer functions for the pos and neg outputs individually.

- In order to calibrate the measurements into transimpedances, New Focus 1611 is used. The output of this PD is AC coupled below 30kHz.
This cutoff was calibrated using another broadband PD (Thorlabs PDA255 ~50MHz).

Result: Attachment 2
- Up to 1MHz, the transimpedance matched well with the expected AF transfer function. At 1MHz the transimpedance is 400.

- Above 1MHz, sharp cut off at 3MHz was found. This is consistent with the openloop TF of LT1128.

 

Attachment 1: OMC_DCPD_Chain.pdf
OMC_DCPD_Chain.pdf
Attachment 2: OMC_DCPD_Transimpedance.pdf
OMC_DCPD_Transimpedance.pdf
  236   Wed Aug 26 11:31:33 2015 KojiElectronicsGeneralOMC DCPD in-vacuum electronics chain test

The noise levels of the output pins (pin1/pin6) are measured. Note that the measurement is done with SE. i.e. There was no common mode noise rejection.

Attachment 1: OMC_DCPD_OutputNoise.pdf
OMC_DCPD_OutputNoise.pdf
  239   Sun Sep 6 16:50:51 2015 KojiElectronicsGeneralUnit test of the EOM/AOM Driver S1500118

TEST Result: S1500118

Additional notes

- Checked the power supply. All voltages look quiet and stationary.

- Checked the internal RF cables too see if there is any missing shield soldering => Looked fine

- Noticed that the RFAM detector board has +/-21V for the +/-24V lines => It seems that this is nominal according to the schematic

- Noticed that the RFAM detector sensitivity were doubled fomr the other unit.
  => This is reated to the modification (E1500353) of  "Controller Board D0900761-B Change 1" (doubling the monitor output gain)

- Noticed that the transfer function of the CTRL signal on the BNC and the DAQ output.
  => This is reated to the modification (E1500353) of  "Servo Board D0900847-B Change 1"  (servo transfer function chage)
  => The measured transfer function did not agree with the prediction from the circuit constants in this document
  => From the observation of the servo board it was found that R69 was not 200Ohm but 66.5 Ohm (See attachment 1).
       This explained the measured transfer function. The actuator TF has: P 2.36, Z 120., K -1@DC (0.020@HF)

- Similarly, the TF between the CTRL port on the unit and the CTRL port on the test rig was also modified.

Noise level

Attachment 2

- The amplitude noise in dBc (SSB) was measured at the output of 27dBm. From the test sheet, the noise level with 13dBm output was also referred. From the coherence of the MON1 and MON2, the noise level was inferred. It suggests that the floor level is better than 180dBc/Hz. However, there is a 1/f like noise below 1k and is dominating the actual noise level of the RF output. Daniel suggested that we should check nonlinear downconversion from the high frequency noise due to the noise attenuator. This will be check with the coming units.

Attachment 1: P9037810.JPG
P9037810.JPG
Attachment 2: RF_AM_spectra.pdf
RF_AM_spectra.pdf
  249   Tue Dec 29 12:15:46 2015 KojiGeneralGeneralGlasgow polarizer passed to Kate

The Glasgow polarizer was passed to Kate on Dec 17, 2015.

  262   Fri Jul 22 22:24:05 2016 KojiGeneralGeneralHQEPD inventory

As of Jul 22, 2016
As of Aug 11, 2016

As of Aug 16, 2016


A1-23 in Cage G https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-A1-23
-> Shipped to LLO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8181
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-1
= Replaced C30665 eLIGO PD (SN 01 in Cage G now) ICS: C30665GH-0-00-0001
-> Removed PD@LLO, Waiting for the shipment to CIT

A1-25 in Cage G https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-A1-25
-> Shipped to LLO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8181
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-1
= Replaced C30665 eLIGO PD (SN 02 in Cage G now) ICS: C30665GH-0-00-0002
-> Removed@LLO, Waiting for the shipment to CIT


B1-01 in Cage A https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-B1-01
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-3_2
= replaced C30665 eLIGO PD (SN 11 in Cage A now) ICS: C30665GH-0-00-0011
-> Removed PD@LHO
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8187

B1-16 in Cage A https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-B1-16
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Now in https://ics-redux.ligo-la.caltech.edu/JIRA/browse/ASSY-D1201439-3_2
= replaced C30665 eLIGO PD (SN 12 in Cage A now) ICS: C30665GH-0-00-0012
-> Removed PD@LHO
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8187


C1-05 in Cage F https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-05
-> @CIT contamination test cavity

C1-07 in Cage F https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-07
-> @CIT contamination test cavity


C1-17 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-17
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Left @LHO as a spare

C1-21 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-C1-21
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Left @LHO as a spare


D1-08 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-D1-08
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Moved to Cage A3
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8186
-> Arrived at CIT (Aug 16)

D1-10 in Cage E https://ics-redux.ligo-la.caltech.edu/JIRA/browse/IHGQEX3000-0-00-D1-10
-> Shipped to LHO https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8182
-> Moved to Cage A4
-> Shipped from LHO to CIT https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8186
-> Arrived at CIT (Aug 16)

  264   Mon Aug 15 10:09:10 2016 KojiGeneralGeneralPrev H1 OMC shipped to CIT

Previous H1 OMC shipped from LHO to CIT

https://ics-redux.ligo-la.caltech.edu/JIRA/browse/Shipment-8196

  265   Mon Aug 22 12:58:16 2016 KojiGeneralGeneralUV bond samples -> Garilynn

- FS base + Mounting Prism

- FS or SF2 1/2" piece + FS or SF2 1/2" piece

- FS? plate + FS or SF2 1/2" piece + FS or SF2 1/2" piece + FS? plate

  268   Fri Sep 9 14:34:31 2016 KojiGeneralGeneralItem lending

To 40m

First Contact Kit by Calum

Class A Kapton sheets

 

  269   Fri Sep 9 19:43:32 2016 KojiOpticsGeneralD1102211 OMC Diode Mount Glass Block went to Downs

D1102211 OMC Diode Mount Glass Block (11pcs) have been given to Calum@Downs

  270   Mon Nov 21 21:19:20 2016 KojiOpticsGeneralLWE NPRO Laser / Input Optics / Fiber Coupling

- About 1.5 month ago, an 700mW LWE NPRO has been brought to OMC Lab.

- The SOP can be found here.

- The base was made for the beam elevation of 3" height. Four 1" pedestals were attached to rise the beam elevation to 4".

- The output from the laser is ~740mW

- After the faraday and the BB EOM, the output is ~660mW

- After the usual struggle, the beam was coupled to the SM fiber. The output is 540mW. The coupling efficiency is >80%.

- Will proceed to the OMC cavity alignment.

  271   Wed Dec 7 19:18:10 2016 KojiOpticsGeneralLWE NPRO Laser / Input Optics / Fiber Coupling

FIber Input Mount 132deg
Fiber output mount 275deg
-> 525mW P: 517mW S: 8mW extinction ratio: 0.016

  272   Wed Dec 7 21:18:35 2016 KojiGeneralGeneralOMC placed on the table / the beam roughly aligned

The OMC mode matching sled was fixed on the nominal part of the table. Then the OMC was located at the nominal position marked by three poles.

The input periscope was adjusted to have the input beam roughtly centered on the OMC QPDs. This made the beam from FM2 aligned to the missing CM1, and the beam just went through the hole of the mounting prism. Very promising!

I wanted to use the new (modified) mirror gluing fixture to hold a curved mirror on the mounting prism. It turned out that the fixture was neither cleaned nor assembled. I will ask Downs Team to help me to get the cleaned and assembled fixtures.

Meanwhile, I just reused the original gluing fixture upside down in order to proceed cavity alignment and locking. (Attachment 1)
In fact, once the mirror is placed on the mounting prism, the cavity started to flash without further alignment. I thank for the very precise (repeatable) alignment of the OMC optics and PD/QPDs.

The next steps are initial cavity locking, more alignment, and mode matching.

Attachment 1: DSC_0082.jpg
DSC_0082.jpg
Attachment 2: DSC_0084.jpg
DSC_0084.jpg
  273   Thu Dec 8 21:17:09 2016 KojiGeneralGeneralOMC placed on the table / the beam roughly aligned

The OMC cavity was locked. The alignment was precisely adjusted. The mode matching was optimized by the lens positions. The reflection during the lock is ~0.01 compared to the full reflection on non-resonance, meaning the mode matching is ~99%. The error signal was maximized (i.e. demod pahse was adjusted) by sweeping the modulation frequency. Note that the EOM is broad band. The modulation freq chosen today was 34.6MHz.

Some notes:

- The error signal has not been preamplified at all yet. Because of this, the reflection is very much sensitive to the input offset.

- The OMC needs wind shield to prevent from the noise caused by air turbulance.

- The laser PZT was actuated via the Thorlabs HV amp. Otherwise, the thermal path needs to be configured.

- One of the CCD monitor is dead. Needs more replacement.

- All the electronics should be moved to the rack. This required long BNC and SMA cables.

- The optical table needs cleaning.

  274   Thu Jan 19 20:57:53 2017 KojiSupplyGeneralPurchase

Ordered:

Office Depot
v AA battery Qty. 24
v 9V battery Qty. 4
v Floor cable cover (6ft)

Thorlabs
v HV PZT Driver
v Lenses

ELOG V3.1.3-