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ID Date Authorup Type Category Subject
  4827   Thu Jun 16 00:43:36 2011 KojiUpdateSUSVertex SUS Binary Output Boxes were turned off / need investigation

- I was investigating the SUS whitening issue.

- I could not find any suspension which can handle the input whitening switch correctly.

- I went to 1X5 rack and found that both of the two binary output boxes were turned off.
As far as I know they are pulling up the lines which are switched by the open collector outputs.

- I tried to turn on the switch. Immediately I noticed the power lamps did not work. So I need an isolated setup to investigate the situation.

- The cables are labelled. I will ask steve to remove the boxes from the rack.

  4829   Thu Jun 16 23:19:09 2011 KojiUpdateSUSVertex SUS Binary Output Boxes removed

[Jamie, Koji]

- We found the reason why some of the LEDs had no light. It was because the LEDs were blown as they were directly connected to the power supply.
The LEDs are presumably designed to be connected to a 5V supply (with internal current-limiting resistor of ~500Ohm). The too much current
with the 15V (~30mA) made the LED blown, or the life-time of them shorter.

- Jamie removed all of the BO modules and I put 800Ohm additional resister such that the resultant current is to be 12mA.
The LEDs were tested and are fine now.

- The four BO boxes for C1SUS were restored on the rack. I personally got confused what should be connected where
even though I had labeled for BO0 and BO1. I just have connected CH1-16 for BO0. The power supplies have been connected only to BO0 and BO1.

- I tested the whitening of PRM UL sensor by exciting PRM UL sensor. The transfer function told us that the pendulum response can be seen
up to 10-15Hz. When the whitening is on, I could see the change of the transfer function in that freq band. This is good.
So the main reason why I could not see theis was that the power supply for the BOs were not turned on.

- I suppose Jamie/Joe will restore all of the BO boxes on the racks tomorrow. I am going to make a test script for checking the PD whitenings.

  4834   Fri Jun 17 23:20:05 2011 KojiUpdateLSCSome updates of the LSC screen

Some updates of the LSC screen

- Signal amplitude monitor for the PD signals (--> glows red for more than 1000)

- Kissel Buttons for the main matrices

- Trigger display at the output of the DOF filters

- Signal amplitude monitor for the SUS LSC output (--> glows red for more than 10000)


ADC Over flow monitor is showing some unknown numbers (as ADCs are handled by IOPs).
I asked Joe for the investigation (and consideration for the policies)

Attachment 1: screen.png
  4841   Mon Jun 20 13:48:25 2011 KojiUpdateABSLI-P curve of LightWave M126-1064-700

Hmm. Was the current within the operating range? (i.e. Is it a 700mW laser or a 1W one?)

You can obtain the nominal operating current from the old EPICS values (or some elog entries).

Note that NPROs are designed to be healthy only at around the nominal pumping power
(i.e. thermal gradient, and thermal lensing of the crystal, etc.)


Be aware that this laser should be used under the old SOP. So the appropriate interlocking is mandatory.

And probably we need to modify the SOP such that it reflects the latest situation.


The I-P curve of the LightWave NPRO, which was taken out from the MOPA box, was measured. It looks healthy.

The output power can go up to about 1 W, but I guess we don't want it to run at a high power to avoid any further degradation since the laser is old.

  4873   Thu Jun 23 23:54:29 2011 KojiOmnistructureEnvironmentWe are saved

Sonali, Ishwita, and another anonymous SURF saved the long-lasted water shortage of the 40m

Attachment 1: IMG_0023.jpg
  4905   Wed Jun 29 00:35:36 2011 KojiUpdateLSCnew LSC overview screen 80% done

New LSC screen is 80% completed.

It is now accessible from the LSC menu of "sitemap".

Most of the part in the screen is clickable such that it launches another screen depending on the location of the click.


The bottom part of the screen still need some work.

RFPD screen is temporary

LSC control screen is also temporary

DAC overflow indicators are still broken.

Channel assignment of the whitening filters are arbitrary so far.


Attachment 1: LSC_OVERVIEW.png
  4912   Wed Jun 29 14:43:12 2011 KojiUpdateLSCLSC model updated

LSC model has been updated and running,

- Now the power and signal recycling cavity lengths are named "PRCL" and "SRCL" in stead of three letter names without "L".

- Names for the trigger monitor were fixed. They are now "C1:LSC-DARM_TRIG_MON", etc., instead of "...NORM"

- Channel order of the DC signals for PDDC_MTRX and TRIG_MTRX were changed.

It was "TRX, TRY, REFL, AS, POP, POX, POY" but now "AS, REFL, POP, POX, POY, TRX, TRY".

We should change the locking script to accomodate these changes.

  4915   Thu Jun 30 00:58:19 2011 KojiSummaryLSCLSC whitening filter test

[Jenne, Koji]

We have tested the LSC whitening filters. In summary, they show the transfer functions mostly as expected (15Hz zerox2, 150Hz pole x2).
Only CH26 (related to the slow channel "C1:LSC-PD9_I2_WhiteGain. VAL NMS", which has PD10I label in MEDM) showed different
phase response. Could it be an anti aliasing filter bypassed???

The 32 transfer functions obtained will be fit and summarized by the ZPK parameters.


The CDS system was used in order to get the transfer functions
- For this purpose, three filter modules ("LSC-XXX_I", "LSC-XXX_Q", "LSC-XXX_DC") were added to c1lsc
in order to allow us to access to the unused ADC channels. Those filter modules have terminated outputs.
The model was built and installed. FB was restarted in order to accomodate the new channels.

- Borrow a channel from ETMY UL coil output mon. Drag the cable from the ETMY rack to the LSC analog rack.
- Use 7 BNC Ts to split the signal in to 8 SMA cables.
- Put those 8 signals into each whitening filter module.

- The excitation signal was injected to C1:SUS-ETMY_ULCOIL_EXC by AWGGUI.
- The transfer functions were measured by DTT.
- The excitation signal was filtered by the filter zpk([150;150],[15;15],1,"n")
   so that the whitened output get flat so as to ensure the S/N of the measurement.

- For the switching, we have connected the CONTEC Binary Output Test board to the BIO adapter module
   in stead of the flat cable from the BIO card. This allow us to switch the individual channels manually.

- The whitening filters of 7 channels were turned on, while the last one is left turned off.
- We believe that the transfer functions are flat and equivalent if the filters are turned off.
- Use the "off" channel as the reference and measure the transfer functions of the other channels.
- This removes the effect of the anti imaging filter at ETMY.

- Once the measurement of the 7 channels are done, switch the role of the channels and take the transfer function for the remaining one channel.


- We found the following channel assignment

  • The ADC channels and the PDs. This was known and just a confirmation. 
  • The ADC channels and the WF filter on MEDM (and name of the slow channel)

- We found that the binary IO cable at the back of the whitening filter module for ADC CH00-CH07 were not connected properly.
This was because the pins of the backplane connector were bent. We fixed the pins and the connector has been properly inserted.

- CH26 (related to the slow channel "C1:LSC-PD9_I2_WhiteGain. VAL NMS", which has PD10I label in MEDM) showed different
phase response from the others although the amplitude response is identical.

Summary of the channel assignment (THEY ARE OBSOLETE - SEPT 20, 2011)

ADC                    Whitening Filter
CH  PD                 name in medm   related slow channel name for gain
00  POY11I             PD1I           C1:LSC-ASPD1_I_WhiteGain. VAL NMS
01  POY11Q             PD1Q          
02  POX11I             PD2I           C1:LSC-SPD1_I_WhiteGain. VAL NMS
03  POX11Q             PD2Q           C1:LSC-SPD1_Q_WhiteGain. VAL NMS
04  REFL11I            PD3I           C1:LSC-POB1_I_WhiteGain. VAL NMS
05  REFL11Q            PD3Q           C1:LSC-POB1_Q_WhiteGain. VAL NMS
06  AS11I              PD4I           C1:LSC-ASPD2_I_WhiteGain. VAL NMS
07  AS11Q              PD4Q           C1:LSC-ASPD2_Q_WhiteGain. VAL NMS
08  AS55I              AS55_I         C1:LSC-ASPD1DC_WhiteGain. VAL NMS
09  AS55Q              AS55_Q         C1:LSC-SPD1DC_WhiteGain. VAL NMS
10  REFL55I            PD3_DC         C1:LSC-POB1DC_WhiteGain. VAL NMS
11  REFL55Q            PD4_DC         C1:LSC-PD4DC_WhiteGain. VAL NMS
12  POP55I             PD5_DC         C1:LSC-PD5DC_WhiteGain. VAL NMS
13  POP55Q             PD7_DC         C1:LSC-PD7DC_WhiteGain. VAL NMS
14  REFL165I           PD9_DC         C1:LSC-PD9DC_WhiteGain. VAL NMS
15  REFL165Q           PD11_DC        C1:LSC-PD11DC_WhiteGain. VAL NMS
16  NC (named XXX_I)   PD5I           C1:LSC-SPD2_I_WhiteGain. VAL NMS
17  NC (named XXX_Q)   PD5Q           C1:LSC-SPD2_Q_WhiteGain. VAL NMS
18  AS165I             PD6I           C1:LSC-SPD3_I_WhiteGain. VAL NMS
19  AS165Q             PD6Q           C1:LSC-SPD3_Q_WhiteGain. VAL NMS
20  REFL33I            PD7I           C1:LSC-POB2_I_WhiteGain. VAL NMS
21  REFL33Q            PD7Q
           C1:LSC-POB2_Q_WhiteGain. VAL NMS
22  POP22I             PD8I
           C1:LSC-ASPD3_I_WhiteGain. VAL NMS
23  POP22Q             PD8Q
           C1:LSC-ASPD3_Q_WhiteGain. VAL NMS
24  POP110I            PD9I
           C1:LSC-PD9_I1_WhiteGain. VAL NMS
25  POP110Q            PD9Q
           C1:LSC-PD9_Q1_WhiteGain. VAL NMS
26  NC (named XXX_DC)  PD10I
          C1:LSC-PD9_I2_WhiteGain. VAL NMS
27  POPDC              PD10Q
          C1:LSC-PD9_Q2_WhiteGain. VAL NMS
28  POYDC              PD11I
          C1:LSC-PD11_I_WhiteGain. VAL NMS
29  POXDC              PD11Q
          C1:LSC-PD11_Q_WhiteGain. VAL NMS
30  REFLDC             PD12I
          C1:LSC-PD12_I_WhiteGain. VAL NMS
31  ASDC               ASDC
           C1:LSC-PD12_Q_WhiteGain. VAL NMS

Attachment 1: chans_24_31_WeirdPhase.pdf
Attachment 2: Octopus.jpg
Attachment 3: Test_Inputs_Plugged_In.jpg
Attachment 4: Contec_Tester_Board.jpg
  4970   Fri Jul 15 01:11:21 2011 KojiSummarySUSPhotosensor Head Lessons

Rotate the PDs and the LED so that you can put them as close as possible.
This is to increase the sensitivity of the sensor. Think why the closer the better.

  5003   Wed Jul 20 18:44:54 2011 KojiSummarySUSWeekly Summary

Find Frank and ask him about those components.

  5064   Sat Jul 30 00:33:33 2011 KojiUpdatePSLABSL Laser crystal temp left largely excited & left unattended for more than 3hours

I found that the ref cav trans CCD view was blinking with 30-50 fringe amplitudes. This meant the laser freq was swinging ~50GHz.

I checked the ABSL laser and the SG out of a lock-in amplifier was connected to the slow input.

This was shaking the laser temp from 29degC to 46degC. This was the cause of the fringe swinging.
This big excitation changing the output power too as the temp was changed across it mode-hop region.

I have disconnected the excitation from the laser no matter how useful experiments were took place as there was no e-log entry about this.

I need the explanations

1. Why our precious laser is exposed to such a large swing of temperature?

2. Why the excitation is left like that without any attendance?

3. Why there was no elogging about this activity?

  5086   Mon Aug 1 23:26:32 2011 KojiUpdateLSCREFL33 PD

Old MZ PD (InGaAs 2mm, @29.5MHz) has been modified for REFL33.
There has been no choice for the 11MHz notch other than putting it on the RF preamp
as the notch in parellel to the diode eats the RF transimpedance at 33MHz.

I wait for judgement of Rana if the notch at the MAX4107 feedback is acceptable or not.


Attachment 1: REFL33_schematic_110801_KA.pdf
  5101   Wed Aug 3 02:20:33 2011 KojiUpdateLSCREFL165 PD

REFL165 PD has been made from the old 166MHz PD.
As the required inductance was ~10nF level, the stray inductance of the circuit pattern was significant.
So, I am not so confident with the circuit functionality before the optical transfer function test.

I will test REFL33 and REFL165 with the Jenne laser to see how they work.



Attachment 1: REFL165_schematic_110802_KA.pdf
  5108   Wed Aug 3 12:37:57 2011 KojiSummarySUSWeekly Summary

I vote for making an adapter plate between the sliding plate and the bottom base.


This morning, I realized that the current set-up of the horizontal shaker does not allow for the TT to be securely mounted. I was going to change the drill holes in the horizontal slider base (1 inch pitch). Jamie has suggested that it is better to make a pair of holes in the base larger. The circled holes are the ones that will be expanded to a 0.26" diameter so that I can mount the mirror securely to the horizontal slider base. There is a concern that a bit of the TT suspension base will hang over the edge of the horizontal sliding plate. We are not sure if this will cause problems with shaking the mirror evenly. Suggestions/advice are appreciated.


  5112   Wed Aug 3 22:22:47 2011 KojiUpdateLSCREFL165 PD

This REFL165 was good in terms of RF, but I forgot to make the DC path functioning.

I will try some ideas to fix this tomorrow.

  5113   Wed Aug 3 22:31:38 2011 KojiUpdateLSCREFL33 PD

REFL33 is ready for the installation

Characterization results of REFL33 is found in the PDF attachment.

Resonance at 33.18MHz
Q of 6.0, transimpedance 2.14kOhm
shotnoise intercept current = 0.52mA (i.e. current noise of 13pA/rtHz)

Notch at 10.97MHz
Q of 22.34, transimpedance 16.2 Ohm

Notch at 55.60MHz
Q of 42.45, transimpedance 33.5 Ohm


Attachment 1: REFL33_test_110801_KA.pdf
REFL33_test_110801_KA.pdf REFL33_test_110801_KA.pdf REFL33_test_110801_KA.pdf REFL33_test_110801_KA.pdf
  5117   Thu Aug 4 09:42:19 2011 KojiUpdateABSLABSL Laser shutter closed

The shutter of the ABSL laser is closed for the vent work.

  5121   Fri Aug 5 04:03:16 2011 KojiUpdateLSCREFL165 PD

REFL165 PD was made and tested. The characterization results are in the PDF file.

Resonance at 166.12MHz
Q of 7.3, transimpedance 667Ohm (Series Resistance = Z/Q2 = 2.5Ohm)
shotnoise intercept current = 4.3mA (i.e. current noise of 36pA/rtHz) 

As the circuit pattern had ~10nH level strain inductance, some technique was needed.

  • The diode was pushed in so as to reduce the lengths of the legs as short as possible.
  • The inductor for the resonant circuit has been located as close to the photodiode as possible
  • The other side of the inductor was needed to be bypassed by a large (0.1uF) capacitor, as the original circuit pattern (D1-L5-C33//R22) was too skinny and long.
  • C32 is also moved next to the diode.
  • The path of the photo current circuit was made thicker by Cu tapes.

Now the size of the loop for the resonant circuit is comparable with the size of SOIC-8 opamp.
(Left-Top corner of the photo)

This improved the resonant gain by factor of 8.5dB at the test with TEST INPUT. (Analyzer photo)

There is no tunable component.
The resonant freq was adjusted by a parallel inductance (270nH) to the main inductor (15nH).



Attachment 3: REFL165_test_110804_KA.pdf
REFL165_test_110804_KA.pdf REFL165_test_110804_KA.pdf REFL165_test_110804_KA.pdf REFL165_test_110804_KA.pdf
  5155   Tue Aug 9 15:14:46 2011 KojiUpdateGeneralin-vac work plan today

This morning Kiwamu and I have aligned the MC. Kiwamu aligned the last steering (on the OMC table) to recover the touch last week.
Then I have aligned the MC with MC1 and MC3 as the last steering did not help to get TEM00.


C1:SUS-MC1_PIT_COMM = 2.6587
C1:SUS-MC1_YAW_COMM = 2.7471
C1:SUS-MC2_PIT_COMM = 3.486
C1:SUS-MC2_YAW_COMM = -1.1592
C1:SUS-MC3_PIT_COMM = -1.876
C1:SUS-MC3_YAW_COMM = 1.2829


C1:SUS-MC1_PIT_COMM = 2.7596
C1:SUS-MC1_YAW_COMM = 2.6627

C1:SUS-MC2_PIT_COMM = 3.486
C1:SUS-MC2_YAW_COMM = -1.1592
C1:SUS-MC3_PIT_COMM = -1.697
C1:SUS-MC3_YAW_COMM = 1.2901


We will move on to the vertex region today.

The goal of the vertex region work is to get the pick-off beams out the chambers, including POX/Y and POP.

The work will be in parallel to the ETM woks.

The first step will be : lock and align MC with the IR beam.


  5163   Wed Aug 10 01:40:40 2011 KojiUpdateSUSETMY exploration

[Rana Koji Jenne Jamie]

- The situation of the ETMY suspension is improved.
- The damping servos except for Pitch are now functional.
- We intentionally turned off the damping servos for the matrix measurements.

- Opened the light door of the ETMY chamber.

- We set up the CDS SUS lockin:

        Excite UL/UR/LL/LR equally [by setting the output matrix (1, 1, 1, 1, 0)] at 3.12Hz with 2000 cnts
        Put the OSEM PD outputs into lockin one by one. For the image rejection, 0.1Hz 4th order LPF has been used though we like to use a faster settling LPF.

- Found only UL was responding to the excitation. After fitzing with the cables and connectors, it was found that the DAC card was loose from the bus.
  By pushing the card the responses have been back. [Note we had the reboot of c1iscey almost at the same time.]

- Checked the response in the I channel of the lockin.
        UL -8ish / UR +7ish / LR +5ish / LL +2ish

- Tweaked LL sensor to get better response ==> in vain. Decided to move the lower OSEM plate for the better positioning of the LR/LL.
- Got reasonable (+5ish) response for LL.

- Confirmed that the POS/YAW/SIDE damping works with positive gains. PITCH did not work with the negative gain (but that could be a good sign.)

- Let the suspension freely swinging for a while (~30min). Checked the side/pos separation. They are not perfect but seemed diagonalizable.

- Closed the light door.

- Jenne will make a better kick/free-swing test later.

  5192   Thu Aug 11 14:32:12 2011 KojiSummarySUSPhotosensor Head Calibration Curve for TT Frame

The entry was quite confusing owing to many misleading wordings.

- The PS2 should be calibrated "as is". (i.e. should be calibrated with the frame)

- The previous calibrations with the highly reflective surface were 0.32V/mm and 0.26V/mm, respectively.
  This time you have 0.10V/mm (with an undescribed surface). The ratio is not 32 but 3.2.

- The DC output of PS2 on the shaking setup was 2.5V. The DC output seen in the plot is 3.5V-ish.
This suggests the possibiliteies:
1) The surface has slightly higher reflectivity than the frame
2) The estimation of the distance between the frame and the PS2 during the TF measurement was not accurate.

- The word "DC coupling level" is misleading. I guess you mean the DC value of the vbration isolation transfer function
  of the suspension.


I have re-calibrated the photosensor I used to measure the displacements of the TT frame (what I call "Photosensor 2").

As before, the linear region is about 15.2mm to 25.4mm. It is characterized by the slope -0.0996 V/mm (-0.1 V/mm). Recall that photosensor 1 (used to measure mirror displacements) has a calibration slope of -3.2V/mm. The ratio of the two slopes (3.2/0.1 = 32). We should thus expect the DC coupling level to be 32? This is not what we have for the DC coupling levels in our data (2.5 for flexibly-supported, fully-assembled TT (with EDC, with bar), 4.2 for EDC without bar, 3.2 for rigid EDC without bar, 3.2 for no EDC, with bar, 3.2 for no EDC without bar) . I think I may need to do my calibration plot for the photosensor at the frame?



  5198   Thu Aug 11 18:30:40 2011 KojiUpdateSUSITMY OSEM adjustment

[Jamie, Koji]

ITMX OSEMs were adjusted so as to have the right DC numbers and the more uniform response to POS excitation.

It is waiting for the free-swinging test.

- ITMX was moved from its position to the north side of the table.

- The table was rebalanced.

- We found that the output of the LR OSEM has an excess noise compared with the other OSEMs.
We tried to swap the LR and SD OSEMs, but the SD OSEM (placed at the LR magnet) showed
the same excess noise at around 10-50Hz.

- We found that one of the EQ stops was touching the mirror. By removing this friction, all of the OSEMs
come to show similar power spectra. Good!

 - Then we started to use LOCKIN technique to measure the sensitivity of the OSEMs to the POS excitation.

Originally the response of the OSEMs was as follows
UL 3.4 UR 4.3 
LL 0    LR 2.5   

After the adjustment of the DC values, final values became as follows
UL 3.9 UR 4.4
LL 3.9  LR 3.2

- We decided to close the light door.

  5224   Sat Aug 13 19:08:01 2011 KojiSummarySUSTT Optimization Curves

What are the parameters you are using? As you have the drawings of the components, you can calculate the masses of the objects.


Reducing the ECD resonance from 10Hz->6Hz looks nice.

The resonant freq of the ECDs are not (fully) determined by the gravitational energy but have the contribution of the elastic energy of the wire.

Q1: How much is the res freq of the ECDs if the freq is completely determined by the grav energy? (i.e. the case of using much thinner wires)

Q2: How thin should the wires be?

  5226   Sat Aug 13 21:48:17 2011 KojiSummarySUSTT Optimization Curves

1) Drawing has the dimensions => You can calculate the volume => You can calculate the mass
Complicated structure can be ignored. We need a rough estimation.

2) Your restoring force can have two terms:
- one comes from the spring constant k
- the other from the gravity


  5336   Fri Sep 2 15:56:32 2011 KojiUpdateIOOtriple resonant box : ready to install

What are the reflected RF powers for those frequencies? 
Is the 29.5MHz more problem than the 55MHz, considering the required modulation depth?


  5431   Fri Sep 16 11:15:12 2011 KojiUpdateIOOPZT1 situation

[Koji Kiwamu]

- We have checked the situation of the broken Piezo Jenna PZT (called PZT1)

- Tested PZT1 by applying a dc voltage on the cables. Found that pitch and yaw reasonably moving and the motions are well separated each other.
  The pitch requires +20V to set the IPPOS spot on the QPD center.

- Made a high-voltage (actually middle voltage) amp to convert +/-10V EPICS control signal into -5 to +30V PZTout. It is working on the prototype board and will be put into the actual setup soon.


- The Piezo Jenna driver box has 4 modules. From the left-hand side, the HV module, Yaw controller, Pitch controller, and Ben abbot's connector converter.

- We checked the voltage on Ben's converter board. (Photo1)
  It turned out that the red cable is the one have the driving voltage while the others stays zero.

- We hooked a 30V DC power supply between the red cable and the shield which is actually connected to the board ground.

- Applying +/-10V, we confirmed the strain gauge is reacting. If we actuated the pitch cable, we only saw the pitch strain gauge reacted. Same situation for yaw too.

- Kiwamu went to IPPOS QPD to see the spot position, while I change the voltage. We found that applying +20V to the pitch cable aligns the spot on the QPD center.


- I started to make a small amplifier boards which converts +/-10V EPICS signals into -5V to +30V PZT outs.

- The OPAMP is OPA452 which can deal with the supply voltages upto +/-40V. We will supply +/-30V. The noninerting amp has the gain of +2.

- It uses a 15V zener diode to produce -15V reference voltage from -30V. This results the output voltage swing from -5V to +35V.
The actual maximum output is +30V because of the supply voltage.

- On the circut test bench, I have applied +/-5V sinusoidal to the input and successfully obtained +5V to +25V swing.

- The board will be put on Ben's board today.

Attachment 1: P9151574.JPG
Attachment 2: P9161576.JPG
Attachment 3: P9161577.JPG
  5447   Sat Sep 17 14:04:45 2011 KojiUpdateIOOPZT1 driver in place

The PZT driver is now in place. The actual PZTs are not connected yet!

It is accommodated on Ben's connector adapter board.

The panel has additional connectors now: two inputs and a power supply connector.

The supply voltage is +/-30V (actual maximum +/-40V), and the input range is +/-10V
which yields the output range of -5V to 30V. The gain of the amplifier is +2.

It is confirmed that the HV outputs react to the epics sliders although the PZT connector is not connected yet
so as not to disturb the locking activity.

When we engage the PZT connector, we should check the HV outputs with an oscilloscope to confirm they
have no oscillation with the capacitances of the PZTs together with the long cable.

Attachment 1: P9171579.JPG
Attachment 2: P9171580.JPG
  5449   Sun Sep 18 15:34:09 2011 KojiUpdateAdaptive FilteringModifications to LSC, RFM models, added OAF model

[Koji Kiwamu]

This modification of the LSC model made the rows of the LSC output matrix shifted. This caused the ASS scripts nonfunctional.

Kiwamu fixed the channel names in the ASS script.


[Jenne, Mirko, with supervision from Jamie]

I modified the c1lsc model to have shmem outputs that go from the degrees of freedom to the OAF, and shmem inputs from the OAF's output to sum into the DoFs, just like Yoichi's FF stuff.  I also removed the old OAF_OUT, because it would only allow me to select one DoF at a time, and I will eventually want the ability to do multiple amounts of OAFing at the same time.  Hopefully.


  5450   Sun Sep 18 15:57:00 2011 KojiUpdateIOOThe PZT driver engaged to PZT1

[Koji Kiwamu]

The pzt driver for PZT1 has been installed.
As there was unknown resistive connection in the vacuum chamber as described below,
the PZT out cable at the PJ driver module should always be disconnected.
The sensor cables have no problem to be connected to the controller.
In fact, they are a good monitor for the state of the PZTs.

In this configuration, Pitch and Yaw direction of PZT1 is under the control of the EPICS value as we expected.


- At the beginning, we tested the PZT driver output with low voltage level (~10V). We did not see any oscillation of the opamps.
  The pitch output was observed to be OK, while the YAW output exhibited a half of the expected output voltage.
  The opamp was holding correct voltage, however the voltage after the 1K output resister was about a half.
  This indicated there was a voltage division happening.

- The cause of the voltage division was tracked. We found that the yaw red (=hot) line is connected to pitch black
  in the vacuum chamber with a resistance of 1.4kOhm. The black cables are shorted to the ground level in the PJ driver.

- We decided to unplug the PJ's cable so that we can isolate the black cables while hoping the PZTs were drived only
  by the red and white cables. And they did.

- This means that we should not connect the PZT driving cable to the PJ's driver. The sensors have no problem to be connected.

- Pinouts:

|. .|
|. .|
|. o|  5
|o  | 17
|  o|  4 
|o  | 16   Yaw Black
|  o|  3   Pitch Black
|o  | 15   Yaw White
|  o|  2   Yaw Red
|o  | 14   Pitch White
 \ o|  1   Pitch Red

* Pitch White and Yaw White are connected to the ground at the amplifier side.
* Yaw Red and Pitch Black is connected with 1.4kOhm and isolated from the others.

  5451   Sun Sep 18 16:42:00 2011 KojiBureaucracyEnvironmentClean up your mess

Mess in the lab is increasing. Kiwamu and I had to clean up some stuffs to continue our work.
(i.e. some components were disturbing to open the lid of the tables.)

Basically the tools/equipments/component/cables/digital cameras/lens caps/IR viewers
you have used for the day should be cleaned up at the end of the day.

If one likes to leave a temporary stuff, leave a note to indicate by whom, for what, how long
it will be kept like that, and when one is going to back there with contact info like the cell phone #.

  5473   Tue Sep 20 02:21:10 2011 KojiUpdateLSCLSC MEDM screen cleaning up

I have made some cleaning up of the LSC-related MEDM screens.

- LSC overview screen: ADC OVFL and WFAA indicators are now correctly matched to it associated PD signals.

- Whitening screens now have the correct indication of the associated PD signals.

- LSC Ctrl screen, which is invoked from the overview screen by clicking the servo filters, now has the switches of the servo filters.

- LSC tab of the sitemap was cleaned up by removing the broken links.

  5481   Tue Sep 20 15:39:57 2011 KojiUpdateSUSfree swinging test in vacuum condition

Can't we use Yuta's auto-Q adjust script?


Edit by KI :

Of course we can use it but first we have to fix some pynds sentences since his script was written for the OLD pynds.

  5492   Tue Sep 20 23:59:53 2011 KojiSummaryLSCPlan to update the LSC code for multiple lock-ins

DRMI team needs to use at least three lockins on LSC

  • Increase the number of the lockin matrix  done
  • Duplicate lockin modules in the LSC code  done
  • modify the main LSC screen done
  • modify the lockin screen done
  • modify the lockin matrix screen done
  5498   Wed Sep 21 14:28:25 2011 KojiSummaryLSCThe LSC code/screen modification for LSC LOCKINs

The LSC code has been modified

- The code was modified, compiled, and installed.

- The code is now running. FB was restarted to deal with the change of the channel names.

- Now we have LOCKIN1, 2, and 3. This required the change of the names from C1:LSC-LOCKIN_.... to C1:LSC-LOCKIN1_...


- The LSC screen has also modified. It has three lockins on the screen.

- The corresponding matrix screens have been modified/created and linked from the main screen.

- I need to make the screens more cool but the locking team can start to use those lockins.

  5516   Thu Sep 22 11:50:37 2011 KojiUpdateLSCLocking status update

Both loops basically have no phase margins. i.e. unstable. How can you lock PRMI with these servos?


The following rough swept sine plots are the OLTs for MICH and PRCL. The gain setting was -10 and 0.5 for MICH and PRCL, respectively. Integrators were off. Looking at the measured plots, MICH has about 300 Hz UGF, when the gain is -20, and PRCL has about 300 HZ UGF, too, when the gain is 0.8.


  5522   Thu Sep 22 18:33:01 2011 KojiSummaryLSCThe LSC screen modification

As per the request of Anamaria, I have added the slider of the demodulation phase for each RF PD screens.

Attachment 1: PD_screen.png
  5528   Thu Sep 22 23:18:51 2011 KojiSummaryLSCThe LSC screen modification


C1LSC_RFPD.adl screen was modified to have more information.

Attachment 1: C1LSC_RFPD.png
  5539   Sat Sep 24 17:12:54 2011 KojiUpdateLSCRealignment of REFL / Some 3f PRMI locking / Recycling Gain

[Koji Suresh]

Activity on Friday evening

- The REFL path has been thoroughly aligned
As I did not like the REFL spot misaligned on the REFL CCD, we went to the AP table.
Many optics had the spots not on the middle of the optic, including the PBS whose post was not fixed on the post holder.
We aligned the optical paths, the RF PDs, and the CCD. The alignment of the PD required the use of the IR viewer.
One should not trust the DC output as a reference of the PD alignment as it is not enough sensitive to the clipping.

We aligned the optical paths again after the reasonable alignment of PRM is established with the interferometer.
"Next time when you see REFL spot is not at the center of the camera, think what is moved!"

- The REFL165 PD is disconnected from the power supply
I found that the REFL165 PD is producing 7.5V output at the DC monitor no matter how the beam is blocked.
As I could not recover this issue by swapping the power connector at the LSC rack, I disconnected the cable
at the RFL165 PD side. I need to go through the PD power supply circuit next week.

- PRMI alignment policy of the night

Kiwamu has aligned Y-arm some time ago (Thursday evening?). I decided not to touch ITMY.
So the Michelson is aligned by ITMX, PRC is aligned by PRM.

- Michelson locking

The short Michelson was locked with AS55Q and the MICH filter. We could use the gain of +/-20 for locking,
and could increase it up to ~+/-250. At the max gain, the all three integrators and the two resonant gains
could be activated. The sign depends on which fringe you want at the AS port (bright or dark).

In this condition, the output of the POXDC channel (which is actually the POY DC out -- c.f. This entry
is used to determine the internal power. It was ~70cnt.

- PRMI locking

Then the PRMI was locked. There was some confusion of the gains because of the limitters at the servo filters
(which yielded the locking with 1bit outputs no matter how much the gains were....)

After all, I decided to use REFL33I for the PRCL for the test. The PRCL gain was -0.3~-1.0 for the carrier lock, but
was highly dependent on the alignment. i.e. if accidentally hit the high power recycling gain, it oscillated easily
and the lock was lost. Probably this was the first 3f locking at the 40m in the current optical config, if
Kiwamu did not do that secretly. The SB lock was also obtained by flipping the sign of the PRCL servo.

The difficulty we had was the instability when the recycling gain became big. We were monitoring the POXDC
(i.e.DCout of the POY PD). When this exceeds 5000, many glitches appears in the LSC signals and disturbs the lock.
This was not the fringes from neither the arms nor the SRC.

The observed POY DC with the carrier resonant PRMI was 5000~8000vcnt (momentary).

  5541   Sat Sep 24 20:14:36 2011 KojiUpdateLSCRough estimation of the PR gain


POXDC (i.e. POY DCout)
PRM misaligned: 70cnt
CA resonant PRMI: ~8000cnt (max)


PRMI antiresonant = 5200cnt
PRMI resonant = ~3000cnt
==> Visivility = 0.6

Transmissivity: TR=0.0575, tR=sqrt(TR)

Rough estimation of the power recycling gain (assuming perfect mode matching)

PPRM_mialign = Pin tR2
PPRM_resonant = Pin [tR/(1-rR rMI)]2

G = tR2 PPRM_resonant / PPRM_mialign = 8000/70*0.0575 = 6.5

This is way too low compared with the design (G>40)
This corresponds to rMI2=0.885 (loss of 10%) in the power recycling cavity.
But this yields visibility of 16%, instead of 60% which we saw. This is inconsistent.

If mode matching is not perfect, effective incident power of PRMI decreases
and this discrepancy may be explained

Pin = Pjunk + (Pin-Pjunk)

PPRM_mialign = Pin tR2
PPRM_resonant = (Pin-Pjunk) [tR/(1-rR rMI)]2

PREFL_antires ~ Pin
PREFL_resonant = Pjunk+(Pin-Pjunk)[-rR+(tR2 rMI)/(1-rR rMI)]2


PPRM_resonant / PPRM_mialign = (1-Rmm) /(1-rR rMI)2=8000/70
PREFL_resonant /PREFL_antires= Rmm+(1-Rmm)[-rR+(tR2 rMI)/(1-rR rMI)]2=0.6

here Rmm= Pjunk/Pin is the mode matching ratio

Solving the last two equations, we obtain

rMI2= 0.939 (loss of 4-5%)

Can we believe that the mode matching is 60% and the loss is 5%???

  5549   Mon Sep 26 17:49:51 2011 KojiUpdatePSLc1psl

[Koji Suresh]

c1psl has got frozen during our ezcaread/write business.
After the target was rebooted and we lost the previous setting as there was no burt snapshot for the slow targets since Dec 13, 2010.

It seems that burtrestore is essential for the bootstrapping of the MC servo, as the auto locker script refers the locking parameters
from the PSL setting values (C1PSL_SETTINGS_SET.adl).

Jenne is working on the recovery of the snap-shotting for the slow targets.

  5551   Mon Sep 26 20:04:03 2011 KojiUpdatePSLMC lock has been recovered

[Kiwamu Suresh Koji]

Some main parameters of the PSL has been recovered using Dataviewer and some screen snapshots, as seen in the screenshots below.

Attachment 1: snapshot1.png
Attachment 2: snapshot2.png
Attachment 3: snapshot3.png
  5559   Tue Sep 27 20:02:19 2011 KojiUpdateSUSWatchdog rearmed

I came to the control room and found the PMC and IMC were unlocked. ==> Relocked
I found the watch dogs of the vertex suspensions are tripped.

I checked the data for the past 6 hours and found they are independent events.
The unlock of the MCs occured 4 hours ago and the watchdogs tripped 2 hours ago.

The suspension damping was restored at around 7:50PM PDT.

  5584   Fri Sep 30 08:40:02 2011 KojiUpdateLSClength fluctuations in MICH and PRCL

Tip-Tilts has almost no isolation up to 3Hz, and isolation of about 0.5 up to 10Hz.
They have vertical resonances at around 20Hz.

See Nicole's entry




  5591   Fri Sep 30 19:12:56 2011 KojiUpdateGeneralprep for poweroutage


 [Koji Jenne]

The lasers were shutdown

The racks were turned off

We could not figure out how to turn off JETSTOR

The control room machines were turned off

FInally we will turn off nodus and linux1 (with this order).

Hope everything comes back with no trouble

(Finger crossing)

  5592   Sat Oct 1 17:47:21 2011 KojiSummaryGeneralRecovery from the power shutdown

[Steve Koji Kiwamu]

- The storage on linux1 and linux1 itself (with this order) were turned on at 10:30am

- Kiwamu restored the vacuum system

   => opened V4, started TP1 (maglev) and opened V1.

      The pressure went downfrom 2.5 mTorr to the normal level in about 20 minutes.

- A regular fsck of linux1 was completed at 5pm

- Nodus was turned on. Mounting /cvs/cds succeeded

- The control room computers were turned on

- The rack power for FB turned on, FB and megatron started.

- Kiwamu and Koji went through all of the rack powers and started the slow and fast machines.
As we found Solensen for -15V at ETMX was current limited. +/-15V were turned off for now.
==> Kiwamu turned on Solensen again for investigation and found it became okay.
It's now ON.
- c1sus and c1ioo had many red lamps on the FE status screen.
Ran killc1XXX for all of the FE codes on c1lsc and c1ioo.
Then, made software reboot (sudo shutdown -r now)
All of the FEs shows green (after some randome clicking of DIAGRESETs)

- HVs on 1X1 were turned on. The are not vacuum HV, but used only in the air

- Turned on the RF generation box and the RF distribution box

- burtrestore slow machines (c1psl, c1susaux, c1iool0, c1iscaux, c1iscaux2, c1auxex, c1auxey)

  5613   Tue Oct 4 15:43:10 2011 KojiUpdateIOOclosed the shutter before the MC

The shutter before the MC was closed at 3:30 as I started working on the RFAM.

MC REFL (INLOCK): 0.6~0.7
MC TRANS: 50000~52000

  5617   Tue Oct 4 19:06:46 2011 KojiUpdateIOOclosed the shutter before the MC

Finished the work at 6:30

MC REFL (INLOCK): 0.50-0.52
MC TRANS: 54400~547000

RFAM level

Before the work: -48.5dBm for 1.07VDC (both 50Ohm terminated)

Right after the work: -80dBm for 0.896VDC (both 50Ohm terminated)
10min after:   -70dBm
1hour after:   -65dBm
3hours after: -62dBm
1day after (Oct 5, 20:00):    -62.5dBm
2days after (Oct 6, 23:20): -72.5dBm
3 days after (Oct 7, 21:00): -57.8dBm


The shutter before the MC was closed at 3:30 as I started working on the RFAM.

MC REFL (INLOCK): 0.6~0.7
MC TRANS: 50000~52000


  5628   Fri Oct 7 11:45:24 2011 KojiSummaryLSCPOY11 installed, 55MHz PD at POY removed

POY11 PD was installed last night. The lock of the Y arm was confirmed with the POY11I signal.

- The DC transimpedance was modified to be 1010V/A as the incident power is tiny.

- The demodulation phase of the roughly adjusted (148deg) to have PDH signal at the I-phase.
The comparison with AS55I signal exhibits that POY11I have ~150 times weaker signal with 45dB whitening.
(In total 25000 times weaker.)

On the way to make POY11 functioning, there were many fixes at the LSC rack...


- The PD interface cards (power supply for the RFPDs) were checked:
So far the two card at the right hand side were checked. 

Desipite the previous entry reported the issues on those boards, they did not show any problem yesterday.

One hypothetical possibility is the enabling switches that is controlled from the old slow epics targets.

- POY55 was removed

This 55MHz PD is supposed to be installed at POP.
The PD, an RF cable, an RF amp, the power supply of the RF amp were removed.

- POY11 was installed

The PD was placed where the 55MHz was placed.

The beam was aligned on the diode using the IR viewer and the digital multimeter.

The power supply cable and the RF cable for POY on the ITMY table were used.

There were an ND filter on the POY beam path. It was removed.

- On the LSC rack
The PD RF was connected to the patch panel at the top of the rack.

There were loose connectors on the patch panel. Some connectors were tightened on the panel.

I found that POY11 and POX11 had I&Q signal reversely connected to the whitening board.
   ==> These were fixed but
require the orthogonality test again for those channels.

The I phase output of the AS11 demod board had a broken connector. 

The onboard SMA has got disintegrated because of too much twist on the connector.
The board was once removed from the rack and the connector was fixed using a heat gun and soldering.

The DC signals were checked. POYDC was not correctly connected. POYDC were correctly connected to the POYDC channel.

c1lsc was found with the RFM frozen.
The c1lsc machine was soft-rebooted after stopping all of the RT processes.

Once the RT processes came back, they were all burtrestored.

- PDH locking
Restored Y-arm. Locked it with AS55Q.
Ran ASS alignment for Y-arm.
100cnt 150Hz sinusoidal signal is applied to ETMY

Measured the PSD of AS55Q, POY11I, and POY11Q.
Adjusted the demod phase so that the excitation could be minimized in POY11Q.

  5629   Fri Oct 7 11:53:47 2011 KojiUpdateLSCDRMI locked and some plans

- REFL165 PD to be fixed (shows constant high voltage at the DC out)

- Make POP22/110 PD

- Install AS11? or use it as POX11?

- Install POP55

  5634   Fri Oct 7 22:41:05 2011 KojiConfigurationGeneralScript backup fixed

Script backup regularly runs on op340m by crontab,
but the true backup were not taken since Oct 16, 2010
as the backup program was looking at the old script directory.
/cvs/cds/script/backupScripts.pl was modified to look at the new script directory.


$command = "cd /cvs/cds/caltech; /usr/sbin/tar cfX - $EXCLUDE_LIST scripts | bzip2 > $ARCHIVEDIR/scripts_$curdate.tar.bz2";


$command = "cd /opt/rtcds/caltech/c1; /usr/sbin/tar cfX - $EXCLUDE_LIST scripts | bzip2 > $ARCHIVEDIR/scripts_$curdate.tar.bz2";

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