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ID Date Author Typeup Category Subject
  4636   Thu May 5 13:13:32 2011 JenneUpdateLSCNew RFPD screens are in

Joe helped me compile the lsc simulink model, and now we have R&D phase rotation.

Right now, we have to do our own math, and figure out what relative phase to put in.  Soonly, I'll figure out how to do subtraction, and we can put in the measured value.

 

More details when I'm not running around like crazy...

--------------------------------------------------------------------------------------------

Okie dokie.  Last night I had modified the c1lsc.mdl to accommodate the R & D phase rotation.  I also made pretty new screens.  This morning however, the adventures began.....

Under Joe's supervision, I ran "make c1lsc".  The error that came up was something about things not being connected.  Joe assures me that this is a temporary problem, that Rolf is already working on.  The reason is that right now the LSC model is "flat", i.e. it doesn't have a bunch of sub-boxes and sub-screens in the simulink model.  Somehow this causes badness.  Joe stuck all the guts of the LSC model into a sub-model.  He then enabled "top_names", which makes the channels use the name of the sub-model, not the sub-model AND the main model (so since the sub-model is called LSC, our channels are just C1:LSC-OTHER_STUFF, rather than C1:LSC-LSC_OTHER_STUFF).  This fixed things so that the compiling worked (when we did "make c1lsc").  The one other thing that we changed was to delete all of the little "Outs" that were attached to EPICS readouts.  These are unneccessary and don't go anywhere, and when we made the sub-model, they made a bunch of empty outputs (unconnected outs on the main simulink model).  So, after doing that, we were able to compile, and do "make install-c1lsc", and all was good in the world.  Mostly.

Joe then noticed that I was using the CDS part "cdsPhase", which only takes one phase input.  I wanted "cdswfsPhase", which actually does the R&D phase rotation that we want.  Perhaps Alex/Rolf/whoever should change the name of that CDS part.  We switched all of the cdsPhase blocks to be cdswfsPhase, and recompiled.  All was still good in the world.  Mostly.

The last thing that was funny was that when I wanted to execute the medm screens, they would still look at the old _IQ_MTRX_1_1 and _IQ_MTRX_2_1 values, rather than the newly defined _PHASE_R and _PHASE_D channels, even though while editing the medm screen, it looked like it was pointing to the right place.  Anyhow, I opened the text file version of the C1LSC_PDX.adl, and changed the channel names to the _R and _D versions by hand.  I don't know if we edit the screens and run generate_screens.py again, if we'll have to re-edit the .adl text files.

After fixing this, all really was good in the world. 

Perhaps though, this making a subsystem business broke the filters somehow?  Foton is looking at the wrong text file now?  Something?  The filters are all still there, they just got moved down a level.  Joe said that he and Rolf are on it, and he should be able to put the LSC model back to being "flat" in the next few days.

  4637   Thu May 5 13:14:15 2011 kiwamuUpdateLSCchans file for LSC

Foton doesn't correctly display the LSC filter bank file : C1LSC.txt.

Foton tells a lie that they all are empty.

 

The file itself looks fine to me i.e. I can find correct filters in text format.

Looks like someone (maybe Joe and Jenne ?) updated the file. I am not sure if this is the reason or not.

allegra:chans>ls -al | grep LSC
-rw-r--r--  1 controls controls   20659 May  5 11:46 C1LSC.txt

 

NEEDS TO BE FIXED SOON

  4638   Thu May 5 13:55:08 2011 kiwamuUpdateLSCMI locking : calibration of BS and ITMs actuators

EDIT by KI on 15/5/2011:

The calibration of MICH error signal was wrong by a factor of 2.

 

The open loop transfer functions of the Michelson locking have been measured.

The purpose of this excise is to calibrate the coil-magnet actuators on BS and ITMs.

The estimated actuation coefficients are :

 BS = 3.69e-08 [m/counts]
 ITMX = 8.89e-09 [m/counts]
 ITMY = 9.22e-09 [m/counts] 

I guess the accuracy is something like 5 % because the calibration of the MI optical gain relies on a peak-to-peak measurement.

A next step is to calibrate the PRM actuator and the PRC optical gain.


 

(measurement)

The Michelson was locked with different actuators in every measurement. I locked the Michelson to the dark fringe with BS, ITMX and ITMY in each time.

The measured peak-to-peak value in the error signal was 20.2 counts, corresponding to a sensor gain of 5.96e+07 [counts/m]. Note that I used AS55_Q for the locking.

After locking the MI I took the open loop transfer function by injecting broadband noise from DTT.

Then the data were fitted coarsely.  In the fitting I used the resonant frequencies that Leo reported recently (http://blue.ligo-wa.caltech.edu:8000/40m/Mechanical_Resonances).

The Q-values are assumed to be 5 because of the local dampings. As a result the fitting gives us the actuator coefficients.

Here is a plot showing the measured open loop transfer functions. The solid lines represent the fittings.

MICH_OL.png

 

(by the way)

- The delay time including ADC/DAC and RFM looks quite big. According to the fitting the delay is something like 600 usec.

This is about two times larger than the one reported before (see this entry). I will re-measure it with empty filters.

  4639   Thu May 5 14:40:14 2011 KojiUpdateLSCMI locking : calibration of BS and ITMs actuators

I've got confused

1) Are these the DC responses of the coils? If that is true, we need to specify the resonant frequency of each suspension to get the AC response.

2) Are these the AC responses well above the resonant freqs? In that case, The responses should be x.xxx / f^2 [m/counts]

Quote:

The open loop transfer functions of the Michelson locking have been measured.

The purpose of this excise is to calibrate the coil-magnet actuators on BS and ITMs.

The estimated actuation coefficients are :

 BS = 3.69e-08 [m/counts]
 ITMX = 8.89e-09 [m/counts]
 ITMY = 9.22e-09 [m/counts]

  4640   Thu May 5 14:50:30 2011 JenneUpdateLSCchans file for LSC

Quote:

Foton doesn't correctly display the LSC filter bank file : C1LSC.txt.

Foton tells a lie that they all are empty.

 

The file itself looks fine to me i.e. I can find correct filters in text format.

Looks like someone (maybe Joe and Jenne ?) updated the file. I am not sure if this is the reason or not.

allegra:chans>ls -al | grep LSC
-rw-r--r--  1 controls controls   20659 May  5 11:46 C1LSC.txt

 

NEEDS TO BE FIXED SOON

 See my updated elog 4636 for what Joe and I did this morning, and what a possible problem is (making the LSC model into a sub-model).

  4641   Thu May 5 15:05:06 2011 steveUpdatePSLPSL-FSS_RMTEMP is not back

Quote:

Valera and I installed the the temp sensor and the interface box that Rana fixed. This may help with diagnosing the PSL drift.

 I was wrong. Rana did not fix the interface box. I removed the interface box and turned down the HEPA flow  from 100 to 20% on the Variac.

Attachment 1: rtnfxd.jpg
rtnfxd.jpg
  4643   Thu May 5 15:28:23 2011 kiwamuUpdateLSCRe: MI locking : calibration of BS and ITMs actuators

They are the DC responses.

I put the resonant frequencies that Leo reported in the wiki to obtain the DC response.

The resonant frequencies I used are :

  f_BS = 0.957 Hz

  f_ITMX = 0.966 Hz

  f_ITMY = 0.988 Hz

Also I assumed that all the Q-values are 5 due to the damping.

Quote:

I've got confused

1) Are these the DC responses of the coils? If that is true, we need to specify the resonant frequency of each suspension to get the AC response.

2) Are these the AC responses well above the resonant freqs? In that case, The responses should be x.xxx / f^2 [m/counts]

Quote:

 BS = 3.69e-08 [m/counts]
 ITMX = 8.89e-09 [m/counts]
 ITMY = 9.22e-09 [m/counts]

 

  4645   Thu May 5 16:11:22 2011 JamieUpdateLSCchans file for LSC

Quote:

Foton doesn't correctly display the LSC filter bank file : C1LSC.txt.

 This was because of a bug in the RCG for foton filter module naming when top names is being used.  Rebuilding the LSC front-end model with top_names (which was needed to get around another bug in the RCG) broke the filter file.  I manually fixed the file, so it should work now.

  4648   Thu May 5 20:47:41 2011 KojiUpdatePSLPMC aligned

The PMC exhibited the reduction of the transmission, so it was aligned.

The misalignment was not the angle of the beam but the translation of the beam in the vertical direction
as I had no improvement by moving the pitch of one mirror and had to move those two differentially.

This will give us the information what is moving by the temperature fluctuation or whatever.

  4650   Fri May 6 06:36:18 2011 SureshUpdateRF SystemPD DC signals at each port connected

We now have the DC signal from three PDs available in the ADC channels 14,15 and 16.  The signals are from  REFL55, AS55 and POY photodiodes respectively.  As the DC signals on all the other PDs of the same port (REFL, AS and PO)  have the same information we do not need to monitor more than one DC PD at each port.

The LSC PD Interface Card, D990543 - Rev B, can take 4 PDs and provides the DC signals of the PDs on the connector P2 (the lower of the two) on the back plane of the chassis. An adaptor card, D010005-00, plugs into the back plane from the rear of the Eurorack and provides the four DC signals on two-pin lemo sockets.

I have connected the three DC signals from the relevant RF PDs (above) to a DC whitening filter, D990694-B-1 which is associated with the channels 9 to 16 of the ADC card.

The cables are in a bit of a mess right now as some of the PD power supply lines are too short to reach up the the Interface card in the top Eurocart. Steve and I plan to redo some of the cabling later today

 

 


 

  4654   Fri May 6 15:59:40 2011 steveUpdateVACTP3 fore pump replaced

Dry fore pump of TP3 replaced by brand new Varian SH-110  at  1.1 Torr_75,208 hrs

The annuloses were closed off for 25 minutes. We are back to VACUUM NORMAL mode.

The TP3 fore line pressure dropped to 44 mTorr at 25 minutes in operation.......9.4mTorr at day 2 with full annulos load

  4655   Fri May 6 17:11:55 2011 steveUpdateSUSSRM-oplev cable

The SRM qpd cable was removed from the BS-table. It's path was changed from 1x4 to ITMY-table following the inner cable tray.

  4656   Sat May 7 02:52:53 2011 kiwamuUpdateLSCTRY photo diode installed

[Suresh / Kiwamu]

 We installed the TRY photo diode (Thorlabs one) and the ETMYT CCD camera in place on the ETMY table.

Now we can see a signal on the TRY digital channel.

It will be quite useful for the Y arm locking, for instance we can do a triggered locking and the maximization of the intracavity power.

Someone has to install the EMTY trans QPD at some point.

  4657   Sat May 7 10:59:11 2011 SureshUpdateRF SystemRF Source filters changed

 

The SLP-50 filters which were on the 55 MHz lines have been replaced with the SBP-60.  Their respective characteristics are given below:

 

at 55MHz Insertion loss (dB) Return Loss (dB)
SLP-50 4.65 1.5
SBP-60 1.36 23

 

SBP-60 has lower insertion loss and higher return loss.  

This may however change the phase of I and Q in the demod boards and they will therefore need to be readjusted.  Currently the output power level of 55 MHz demod is at 2dBm, whereas it ought to be at 6dBm.   I have not yet corrected that.  Once that is completed Kiwamu will adjust the phases.

 I shifted the temperature sensor to a new location.  See the photograph below.  I noticed that the higher temperature is reached on the side where there are two RF Amps.  So it would be better to check the temperature of that  area and make sure that it remains well below 65 deg.  The operating maxium is 65deg C

 

Here is a picture of the new RF source layout.

RF_Source_Schematic.png

And here is a photograph of it

RF_Source.jpg

 

  4659   Sat May 7 18:08:54 2011 valeraUpdateIOOMC beam spot centering script

I tried to run the scripts/senseMCdecentering to check the centering of the MC beam spots on the mirrors. The script (csh) produces a lot of error messages on the control room machines. They are machine dependent combination of "epicsThreadOnce0sd epicsMutexLock failed", "Segmentation fault", "FATAL: exception not rethrown". Most of ezcawrite commands fail but not all(?). After running the mcassUp script couple of times all the dither lines came on. The MCL responses to dither lines look qualitatively similar to what it was in February (plot attached). The overall MCL spectrum looks ~100 times lower, presumably due to the analog gain reallocation.

Before that I realigned the beam into the PMC, recentered the PSL QPDs, and the beam into the MC to bring the MC RFPD_DC from ~3 to ~1.5 VDC then tweaked MC2 to bring the MC RFPD_DC from ~1.5 to ~1 VDC.

The mcass dither lines are off now and the loops are disabled.

Attachment 1: mcditherlines2.pdf
mcditherlines2.pdf
  4660   Sun May 8 16:32:52 2011 valeraUpdateIOOMC beam spot centering

 Kiwamu told me that the CDS matrix notation has changed and the 40m front end code has changed since February. I changed the senseMCdecentering script to reflect that. The other problems were: the "-" sign in ezcastep on ubuntu is not recognized - I used the known workaround of using "+-" instead; the echo command in csh script on ubuntu does not make a new line - but the echo " " does. The script ran on ubuntu with one error message "FATAL: exception not rethrown" but it finished nevertheless. The data appeared ok.  On centos machine the script produced "Segmentation fault'. The matlab script sensemcass.m now calculates the position on the MC mirrors in mm. The attached table shows the MC spot positions in mm:

    feb 26 2011      may 08 2011
MC1 pit   1.6   1.9
MC2 pit   6.4   9.0
MC3 pit   1.4   2.0
MC1 yaw   -1.5   -1.7
MC2 yaw   1.0   0.2
MC3 yaw   -1.3   -1.9

I had to rephase the lockin digital phases by tens of degrees. I don't know why this should happen at ~10 Hz.

 

  4661   Sun May 8 17:29:01 2011 ranaUpdateIOOMC beam spot centering

It seems like the best option would be to make the MCASS just adjust the SUS biases and center the beams on the suspended optics. Is this not possible somehow?

  4662   Sun May 8 22:59:40 2011 ranaUpdatePSLPSL reference cavity temperature box modifications

I looked at the PSL temperature box. It started out as D980400-B-C. Then it was revised by Peter King as per the LHO mods E020247.

There are some more things to do to it to make it useful for us:

  1. R3, 4, 7, 8, 12, & 13 should be changed from 1k to 0 Ohms, I think. I cannot figure out their purpose.
  2. All resistors should be made metal-film. Right now, its kind of a mish-mash.
  3. The active filter U6B has a corner frequency of ~50 Hz. This seems not useful for keeping the 4116 DAC noise out of the temperature. We should lower this to ~30 mHz to take advantage of the stability of the LT1021 which was put in.

** Frank reminds me that we don't use the TIdal or VME external inputs anymore since we moved to the EPICS/Perl PID control. So all we have to do is make sure these inputs are hardware disabled/disconnected.

  4663   Mon May 9 09:37:51 2011 valeraUpdatePSLPSL and MC trends

The attached plot shows 7 day trends of the MC and PMC power levels, PSL QPDs, and temperature. The MC stayed locked for ~40 hours over the weekend. The temperature swings were somewhat smaller over the past couple of days but one should remember to turn the PSL HEPA down after working on the table. Steve turned the HEPA flow from 100% down to 20% on Thursday and posted the reminder signs on the PSL enclosure.

Attachment 1: pslmcdrift2.pdf
pslmcdrift2.pdf
  4664   Mon May 9 12:33:40 2011 kiwamuUpdateLSCC1:LSC-TRIG_MTRX : wrong matrix size

I found that C1:LSC-TRIG_MTRX has a wrong matrix size. It needs to be fixed.

It is designed to have a 11x8 matrix in the simlink model file, but it's been compiled as a 6x8 matrix.

I recompiled c1lsc but it didn't fix the issue. Here below is the matrix statement in the C file :c1lsc.c. Indeed it is 6x8 matrix ....

// MuxMatrix:  LSC_TRIG_MTRX
for(ii=0;ii<8;ii++)
{
  lsc_trig_mtrx[ii] =
          pLocalEpics->lsc.LSC_TRIG_MTRX[ii][0] * lsc_imux_trigger[0] +
          pLocalEpics->lsc.LSC_TRIG_MTRX[ii][1] * lsc_imux_trigger[1] +
          pLocalEpics->lsc.LSC_TRIG_MTRX[ii][2] * lsc_imux_trigger[2] +
          pLocalEpics->lsc.LSC_TRIG_MTRX[ii][3] * lsc_imux_trigger[3] +
          pLocalEpics->lsc.LSC_TRIG_MTRX[ii][4] * lsc_imux_trigger[4] +
          pLocalEpics->lsc.LSC_TRIG_MTRX[ii][5] * lsc_imux_trigger[5];
 }

  4665   Mon May 9 13:14:48 2011 josephbUpdateLSCC1:LSC-TRIG_MTRX : wrong matrix size

[Joe, Kiwamu]

There is a feature/bug of the RCG code that you can only have 1 receiving tag for every sending tag.  There were 5 tags which were being received by two tags each, for two different matrices.  Only the first tag was receiving, the second was apparently ignored.

This has been fixed temporarily by putting in direct lines in place of these 5 tags.

Quote:

I found that C1:LSC-TRIG_MTRX has a wrong matrix size. It needs to be fixed.

It is designed to have a 11x8 matrix in the simlink model file, but it's been compiled as a 6x8 matrix.

 

  4666   Mon May 9 15:21:36 2011 josephbUpdatePSLFixed channel names for PSL QPDs, fixed saturation, changed signs

[Valera, Joe]

Software Changes:

First we changed all the C1:IOO-QPD_*_* channels to C1:PSL-QPD_*_* channels in the /cvs/cds/caltech/target/c1iool0/c1ioo.db file, as well as the /opt/rtcds/caltech/c1/chans/daq/C0EDCU.ini file.  We then rebooted the frame builder via "telnet fb 8087" and then "shutdown".

This change breaks continuity for these channels prior to today.

The C1:PSL-QPD_POS_HOR and C1:PSL-QPD_POS_VERT channels were found to be backwards as well.  So we modified the /cvs/cds/caltech/target/c1iool0/c1ioo.db file to switch them.

Lastly, we changed the ASLO and AOFF values for the C1:PSL-QPD_POS_SUM and the C1:PSL-QPD_ANG_SUM so as to provide positive numbers.  This was done by flipping the sign for each entry.

ASLO went from 0.004883 to -0.004883, and AOFF when from -10 to 10 for both channels.

Hardware Changes:

The C1:PSL-QPD_ANG_SUM channel had been saturated at -10V.  Valera reduced the power on the QPD to drop it to about 4V by placing an ND attenuator in the ANG QPD path.

  4670   Mon May 9 17:23:25 2011 SureshUpdateRF SystemRF Cables near LSC Rack

[Steve, Suresh]

We started to clean up the RF cables (heliax and PD interface cables)  at the LSC rack.

We have pulled out all the RF cables from the small hole on the side-board close to floor.  Passing the cables through this hole makes some of the cables much too short for good strain relief.  So we removed the side panel on the vacuum tube side and are going to pass the cables into the rack from there at about waist height.  We now have plenty of cable lengths to tie them off to the rack at several points.

We have traced all the available Heliax cables and have attached blank tags to them.  We have allocated some cables to REFL11, REFL55 and AS55.  These are therefore back in working order.  We have also taken stock of the available PD interface cables.  They do not have consistent names on both ends of the cable and we will identify and label the ends tomorrow.

MC is locked.  The auto-locker works fine.

Handing over the system for night time interferometer work now.  Will continue with the cabling tomorrow.

 

  4671   Mon May 9 18:54:29 2011 kiwamuUpdateLSCtriggerd locking logic : screen prepared

I made a new medm screen for the triggering logics. Have fun.

I put a button on C1LSC.adl to invoke this screen.

trigger_medm.png

Quote from #4656

It will be quite useful for the Y arm locking, for instance we can do a triggered locking and the maximization of the intracavity power.

 

  4672   Mon May 9 20:30:20 2011 ranaUpdatePSLPSL reference cavity temperature box modifications

I re-installed the box (@ ~8:15) after reflowing some of the solder joints. I will observe it over night and then remove the 1K resistors. Attached is a 8 hour minute-trend.

Attachment 1: Untitled.png
Untitled.png
  4673   Tue May 10 00:31:28 2011 kiwamuUpdateASCIFO alignment plan

The alignment of the interferometer goes basically step by step.

Tuesday will be an alignment day.

  0. MC beam centering (it's done)

  1. F2P to balance the coils on every optics including BS, PRM, SRM, ITMs and ETMs (Kiwamu).

  2. A2L and then change the DC bias of ITMY and ETMY to get a perfect eigen axis (VF/Jamie).

  3. align input PZT mirrors (PZT1 and 2) to maximize the Y arm transmission (VF/Jamie).

  4. do the same things for X arm but using BS instead of the PZTs.

  5. Alignment of the central part.

  6. Make a script to automatically get those things done. 

  4674   Tue May 10 00:44:52 2011 valeraUpdateIOOMC2 centering

Kiwamu, Koji, Valera

We centered the beam on MC2 in pitch by moving the MC1,2,3 in the following combination [-9,+3,-7]. This actuation vector mostly moves the spot on MC2 vertically. The attached plot shows the dither before and after the centering. We monitored the demodulated signals and saw the reduction of the MC2 pit response from -1.0 to -0.22 which corresponds to the beam spot position change from 9 to 2 mm. Thus all the spots on MC mirrors are within 2 mm of the center. We estimate based on the distance between the MC1-MC3 of 20 cm, the distance from the center between MC1 and MC3 to the end of the Faraday isolator of 80 cm, and the aperture of the FI of 12 mm, the maximum angle out of MC of 3/200 rad. Which implies the maximum differential spot motion of 3 mm not to be limited by the FI aperture.

Attachment 1: mc2centering.pdf
mc2centering.pdf
  4675   Tue May 10 01:39:41 2011 SureshUpdateRF SystemRF source troubles

Today after Steve and I finished the RF cabling work for the day, Kiwamu noticed that there were no RF signals to be seen.  The problem was traced to disconnected 11 and 55 MHz Demod lines from the RF source.  But reconnecting them did not restore the signals.  It turned out that one of the Heliax cables had a loose N-type connector at its end and it finally came off while we were tightening it into place.

We replaced the damaged heliax with another (we have two spare running from 1X2 IOO rack to the 1Y2 LSC rack.  The new cable is used to be the LO 33.  It seems to have a 1.5dB loss.  Have to check this again tomorrow.

In the mean time I noticed that the power output of the 55MHz Demod port of the source was less than about -12dB. So I opened the source to take a look and found that all the voltage stabilisers were supplying 15V.  Even those which were supposed to be supplying 24V.  This was traced to a mistake in wiring the external power supply.  The wires had been labeled wrongly and as a result the 18V input line was connected to 28V source and vice versa.

After fixing this problem I reassembled the source checked the power output on all the ports and found everything was functioning as expected.  However after installation once again the unit failed.  The blue light on the power supply was not lighting up when switched on.  Suspecting a power supply problem I opened the unit again and found that a weak solder joint on one of the RF amplifiers had come loose and had overloaded one of the 24V stabilisers.   We, found a spare and replaced it.  The unit has been reassembled and is functioning fine.  The output power levels are

11MHz Demod -- 6dBm

55MHz Demod -- 5.5 dBm

11MHz EOM --   24dBm

55MHz EOM -- 28dBm

The Marconi is serving as the 11MHz source.  The Wenzel 11MHz source is giving 13.3 dBm and is okay.  But it needs to be checked for its performance as it may have been exposed to higher than rated power supply levels.

The 29.5MHz source is giving 7dBm.  It is supposed to be giving 13dBm. 

The Laboratory DC power supplies currently used for both the RF source and Distribution boxes need to be replaced with rack mounted Sorensen power supplies available in the lab.

 

  4676   Tue May 10 09:05:49 2011 KojiUpdateGeneralaLIGO BBPD / Green PD investigation

BBPD update

- The BBPD circuit has been constructed on the aLIGO BBPD board

- It still keeps 200MHz BW with FDD-100 Si PD for the 100V bias.

- The noise spectrum has been cleaned up a lot more. It shows the noise level of the 0.4mA shotnoise between 9-85MHz.
The noise at 160MHz is the noise level of the 1mA shotnoise.

Some of the noise peaks at around 97MHz came from the bias voltage.

What to do next

- Confirmation of the performance with the original aLIGO BB PD configuration.

- Notch filter for 9MHz (for aLIGO).

- Implementation of a power amplifier. (issues: power supply and heat removal)

Attachment 1: PD_response.pdf
PD_response.pdf PD_response.pdf PD_response.pdf
  4677   Tue May 10 10:06:23 2011 josephbUpdatePSLFixed channel names for PSL QPDs, fixed saturation, changed signs

I added calculation entries to the /cvs/cds/caltech/target/c1iool0/c1ioo.db file which are named C1:IOO-QPD_*_*, as the channels were originally named.  These calculation channels have the identical data to the C1:PSL-QPD_*_* channels.  I then added the channels to the C0EDCU.ini file, so as to once again have continuity for the channels, in addition to having the newer, better named channels.

The c1iool0 machine ("telnet c1iool0", "reboot") and the framebuilder process ("telnet fb 8087", "shutdown") were both restarted after these changes.

These channels were brought up in dataviewer and compared.  The approriate channels were identical.

Quote:

[Valera, Joe]

Software Changes:

First we changed all the C1:IOO-QPD_*_* channels to C1:PSL-QPD_*_* channels in the /cvs/cds/caltech/target/c1iool0/c1ioo.db file, as well as the /opt/rtcds/caltech/c1/chans/daq/C0EDCU.ini file.  We then rebooted the frame builder via "telnet fb 8087" and then "shutdown".

This change breaks continuity for these channels prior to today.

 

  4678   Tue May 10 11:14:44 2011 steveUpdatePSLPSL-QPD_ANG qpd optimized

Valera and I placed F 572.7 mm lens ~15 cm away  from the ang  qpd (in the same mount with ND filter) so that two qpds see different combination of ang and pos motion - there was no lenses prior to this change. The beam diameter is reduced to ~half .

Attachment 1: qpdangl.jpg
qpdangl.jpg
  4679   Tue May 10 16:42:49 2011 josephbUpdateCDSNew upconversion model (c1uct)

[Ryan, Joe]

Ryan added the c1uct (upconversion tester) model to the c1ioo machine.   It is DCU_ID 32, CPU 6.  The relevant wiki page has been updated. It has been added to /diskless/root/etc/rtsystab on the fb machine and automatically comes up when the c1ioo computer is turned on. 

Joe still needs to add its status to the status screen.

It is soft linked from:

/opt/rtcds/caltech/c1/userapps/trunk/CDS/c1/models/c1uct.mdl

Ryan will expand upon its uses later.

  4680   Tue May 10 16:45:19 2011 josephbUpdateCDSc1ass now receiving AS55I from c1lsc

[Valera, Joe]

We added a cdsPCIx_SHMEM connection between the c1lsc and c1ass models.  This connection is called C1:LSC-ASS_AS55I, and sends the normalized AS55I data to Lockin 11 of the c1ass model.

In addition, in order to get the c1ass model to compile, we had to place all the non-IO parts inside a subsystem block, which we called ASS, and gave the top_names tag to.

The c1lsc and c1ass models were rebuilt, the frame builder restarted, and the models restarted.

  4681   Tue May 10 20:57:05 2011 ranaUpdatePSLPSL reference cavity temperature box modifications : after 24 hours still OK

Quote:

I re-installed the box (@ ~8:15) after reflowing some of the solder joints. I will observe it over night and then remove the 1K resistors. Attached is a 8 hour minute-trend.

 I compared this 24 hour trend with the one from this day exactly one year ago. Seems the same, so now I can make the resistor change.

Attachment 1: Untitled.png
Untitled.png
  4682   Tue May 10 22:56:17 2011 kiwamuUpdateSUSf2p filters installed on ETMY

New f2p filters were installed on ETMY. 

The statistical error of the coil gain settings are now about 0.8% at high frequency (i.e. above the resonant freq of the pendulum mode)

 What I did :

 -   measured and corrected the coil imbalances on ETMY using a script called F2P_LOCKIN.py

 -   made the new f2p filters based on the measurements and installed them.

  Next step :

 -  do the same adjustment for all the suspensions including PRM, SRM, BS, ITMs and ETMs

 


(Notes on F2P_LOCKIN.py)

 F2P_LOCKIN.py is a script that I've made in python. This is basically the same as the old script, f2pratio, but uses the realtime LOCKINs instead of ezcademods.

The script automatically measures the coil imbalances on an optics of interest by driving the local LOCKIN oscillators.

In the first step the script automatically balances the coil gains at high frequency (8.5Hz).

In the next step it gives some coefficients, which basically represent the coil imbalances at low frequency (0.01Hz)

Then with those coefficients one will be able to design the f2p filters.

It is not well polished yet, so I will spend some more times to make it user-friendly and readable.

Example usage : F2P_LCKIN.py -o ETMX

It currently resides in /cvs/cds/rtcds/caltech/c1/scriptss/SUS/

 

(new f2p filters)

The plot below shows the new f2p filters. Note that they are already installed.

f2p_etmy.png

Pendulum mode = 0.982 Hz (according to the wiki)
Q of the pendulum mode = 1 (to avoid ringing of IIR filters)
C1:SUS-ETMY_ULCOIL_GAIN = -0.793435
C1:SUS-ETMY_URCOIL_GAIN = 1.16877
C1:SUS-ETMY_LLCOIL_GAIN = 1.25028
C1:SUS-ETMY_LRCOIL_GAIN = -0.730704
UL_fz = 0.965125
UR_fz = 1.029517
LL_fz = 0.934231
LR_fz = 0.996562
UL_Qz = 0.982816
UR_Qz = 1.048388
LL_Qz = 0.951356
LR_Qz = 1.014829
  4683   Tue May 10 23:14:01 2011 kiwamuUpdateSUSETMX_OPLEV : He-Ne laser dead ?

I found that a He-Ne laser which has been used for ETMX_OPLEV was NOT giving the light.

Since I didn't find the switch key for it I have no idea if the laser is simply off or dead.

  4684   Wed May 11 00:23:21 2011 kiwamuUpdateASCY arm and beam pointing alignment

[Jamie / Valera / Kiwamu]

 The incident beam pointing was improved a lot by using C1ASS realtime code.

Some more details will be posted later. The below is the list of the highlights today.

 - The Y arm cavity was aligned to have good beam centering on the mirrors.

 - The input PZTs were also aligned to the aligned Y arm by hand.

 - Automation of the  Y arm alignment using C1ASS_LOCKIN got partially functional with two loops closed. C1ASS correctly servos the centering on ETMY

 - The amount of the off-centering on ITMY and ETMY look roughly within 1 mm.

 - As a result the intracavity power got bigger by a factor of about 3.5

  4686   Wed May 11 11:05:45 2011 steveUpdateSUSETMX_OPLEV : He-Ne replaced

Quote:

I found that a He-Ne laser which has been used for ETMX_OPLEV was NOT giving the light.

Since I didn't find the switch key for it I have no idea if the laser is simply off or dead.

 The dead laser was replaced by new JDSU 1103P of  2.6mW. The return beam is big ~5 mm diameter of 0.3 mW,  1400 counts

Attachment 1: P1070672.JPG
P1070672.JPG
  4687   Wed May 11 11:24:59 2011 steveUpdateSUSSRM-oplev qpd is back

Quote:

The SRM qpd cable was removed from the BS-table. It's path was changed from 1x4 to ITMY-table following the inner cable tray.

 Laser diode oplev SRM is working. Qpd matrix values were reset like others.

In 0.44mW, returning 0.1mW,  -500 counts.

Attachment 1: srm-prm_oplevs.jpg
srm-prm_oplevs.jpg
  4688   Wed May 11 11:44:52 2011 kiwamuUpdateSUSf2p filters installed on ITMY

New f2p filters were installed on ITMY this morning. The statistical error of the coil gain setttigs are about 0.6 % at high frequency.

NEXT : PRM, SRM, BS, ITMX and ETMX.

 

f2p_itmy.png

 Pendulum mode = 0.988 Hz, Q = 1

C1:SUS-ITMY_ULCOIL_GAIN = 1.02482

C1:SUS-ITMY_URCOIL_GAIN = -1.06831

C1:SUS-ITMY_LLCOIL_GAIN = -0.996671

C1:SUS-ITMY_LRCOIL_GAIN = 0.91079

UL: fz = 1.014824 Hz, Q = 1.027150

UR: fz = 0.975038 Hz, Q = 0.98688

LL: fz = 1.000229 Hz, Q = 1.012378

LR: fz = 0.972688 Hz, Q = 0.946116

Quote from #4682

New f2p filters were installed on ETMY. 

The coil imbalances are now about 0.8% at high frequency (i.e. above the resonant freq of the pendulum mode)

  4689   Wed May 11 13:54:32 2011 steveUpdateLSCLSC power supplies

Aux- rack _1Y2 is just behind 1Y3  It contains Kepco Analoge DC power supplies for +- 5, 15 and 24V

Placing these power supplies away from the LSC rack was an effort to minimize pick up from them.

 

Attachment 1: P1070679.JPG
P1070679.JPG
  4693   Wed May 11 21:58:30 2011 ranaUpdateSUSETMX_OPLEV : He-Ne replaced

Quote:

Quote:

I found that a He-Ne laser which has been used for ETMX_OPLEV was NOT giving the light.

Since I didn't find the switch key for it I have no idea if the laser is simply off or dead.

 The dead laser was replaced by new JDSU 1104P of  2.6mW. The return beam is big ~5 mm diameter of 0.3 mW,  1400 counts

 Whenever replacing any Oplev laser, please also put into the ELOG when it was installed so that we have an electronic record of the laser lifetime.

  4694   Wed May 11 22:52:55 2011 kiwamuUpdateLSCstatus update and plan

Rana forced me to write this entry for summary because he didn't come to the 40m meeting today.

Status update :

    Interferometer Input Beam alignment with the PZTs.

     60 % done. The rest of the 40 % is to make the procedures automated.

     The beam spots on ITMY and ETMY are centered within ~1 mm accuracy.

     PRM, BS, ITMX, & ITMY actuator calibrations and PRC/MICH error calibrations

    Ongoing: First we will do it by hand, then some scripts will be made for the calibraion and resultant noise budget.

     F2A Suspension filter calculations.

      ETMY and ITMY are done. Need volunteer for ETMX, ITMX, BS, PRM, & SRM !!

      Bounce-Roll notch filters

      Leo is working on it. 25% complete...

     DC signal from RFPDs

      The RFPDs have a local SMA DC output as well as a DC output from their PD Interface cards in the LSC rack. We have hooked up some of the PD Interface DC outputs to the LSC ADCs but not tested??

Next steps:

  Installation of a temporary (Thorlabs) DCPD on either POY to see the intra-cavity power in the PRC. It would be ridiculous to put detectors on POX or POP since they're still clipped.

  D-phase and amplitude imbalance adjustment of the demod baords.

          make a script which uses pynds.

  Alignment of the full interferomter, starting from the X arm

  Loss measurements for the arms

  Schnupp asymmetry measurement

  

  4695   Wed May 11 22:54:53 2011 JenneUpdateTreasureETMY trans QPD installed

I put the ETMY trans QPD in. 

The ETMY trans beam was already going toward the TRY DC PD, and a CCD camera.  I put a beam splitter in that beam (reducing the power to TRY and the CCD by 50%), and sent my picked-off beam to the ETMY QPD.  Since there is a lens in this path to focus the beam onto TRY and the camera, I put the QPD ~the same distance from the lens as the camera.  Due to space requirements (because of all the green stuff on the table now), I had to put a Y1 turning mirror between the beam splitter and the QPD.  The beam is aligned onto the PD, although the signal isn't super strong.  When the PD is blocked, the sum is ~(-92 counts).  When the beam is on the PD, the sum is ~(-78 counts). 

  4696   Wed May 11 23:02:52 2011 valeraUpdateASSDither angular stabilizitaion system update

This is what was done in past two days:

- The ETMY and ITMY pitch and yaw dofs are modulated at 40, 44, 42, 46 Hz respectively (oscillator A=30). The c1ass lockin numbers are 12, 14, 27, 29.

- The NAS55I signal is demodulated at the above frequencies. The demodulated I/Q signal phase is set to shift all signal into I-phase. The lockin inputs are bandpassed around respective frequency f with butter("Bandpass",2,f-0.5,f+0.5). The demod signals are then additionally low passed with butter ("Lowpass",4,0.5) so the servo ugf has to be below 0.5 Hz. The servo filter is p:z 0.0001:0.1.

- The ETMY demodulated signal is fed back to ITMY and visa versa.

- With the above 2x2 servo running we moved the input beam PZTs by hand to follow the cavity.

- At the end we offloaded the servo control signals to the SUS biases again by hand.

- The beam spot centering was estimated by unbalancing the ETMY/ITMY pitch/yaw coil combinations intentionally by 5%, which produces 1.3 mm shift of the node, and comparing the response to the residual signals.

- The dof set up currently is: ETMY pitch lockin 12 -> dof2, ITMY pitch lockin 14 -> dof4, ETMY yaw lockin 27 -> dof7, ITMY yaw lockin 29 -> dof9

- The next step is to demodulate the TRY(X) and servo the input beam PZTs

  4697   Thu May 12 00:59:45 2011 ryan, ranaUpdatePSLReturn of the PSL temperature box

The PSL temperature box has returned to service, with some circuit modifications. The 1k resistors on all the temp. sensor inputs (R3, R4, R7, R8, R12, R12) were changed to 0 Ohm. Also, the 10k resistors R26, R28, R29, and R30 were changed to 10.2k metal film. The DCC document will be updated shortly. There is now an offset in the MINCOMEAS channel compared to the others, which will be corrected in the morning after looking at the overnight trend.

  4698   Thu May 12 02:31:07 2011 SureshUpdateRF Systeminstallation of RF splitters in Demod boards

[Jamie, Koji, Suresh]

We replaced splitters in several demod boards as per the table given below:

 

Demod boards in which splitter has been replaced on 11May2011
Demod Board S. No. Power Splitter Frequency range of splitter (MHz) Phase unbalance from datasheet (deg) Amplitude Unbalance from datasheet (dB)
REFL55 118 PQW-2-90 30 to 90 90.14 0.92
AS11 021 PSCQ-2-51W 5 to 50 87.49 0.1
POY11 119 PSCQ-2-32 3.2 to 32 87.58 0.05
POY22 020 PSCQ-2-32 3.2 to 32 90.26 0.02
POY110 120 PSCQ--120 80 to 120 90.88 0.58

 

While doing a rough check of the boards I noticed that the REFL11 demod board had no signal on the Q output.

Rana also advised that we must use the boards which have the piggy-back amplifiers on those signals which are most useful.  We referred to Alberto's thesis and chose POY55 (MICH and SRCL), REFL11(PRCL)  and AS55 (DARM) as the most useful signals.  We currently have these amps on AS11, REFL11 and AS55.  We need to convert either AS11 or REFL11 into a POY55.  Since we need to troubleshoot REFL11, I thought we might as well modify that and in the process also fix its Q output.  So I renamed AS11 as REFL11 and will convert the old REFL11 into POY55 tomorrow.

Power splitter of different types have different pin-outs.  The way we mount a splitter depends on which type we are using.   I will detail the mounting scheme in a separate elog tomorrow.

 

 

 

  4699   Thu May 12 05:25:26 2011 kiwamuUpdateIOOIP_POS disconnected

A cable for IP_POS has been disconnected at the LSC rack, 1Y2. Due to it currently no IP_POS signal shows up on the digital side.

It looks like we disconnected the cable together with some unused cables when we were cleaning up the wiring of the LSC rack.

The cable, a shielded flat-cable, is supposed to send DC power to the QPD and send the signals from the QPD to an interface board on the LSC rack.

I will check how it used to be and reconnect it.

  4700   Thu May 12 08:54:11 2011 steveUpdateIOOIP_POS cable found

Quote:

A cable for IP_POS has been disconnected at the LSC rack, 1Y2. Due to it currently no IP_POS signal shows up on the digital side.

It looks like we disconnected the cable together with some unused cables when we were cleaning up the wiring of the LSC rack.

The cable, a shielded flat-cable, is supposed to send DC power to the QPD and send the signals from the QPD to an interface board on the LSC rack.

I will check how it used to be and reconnect it.

 I found the disconnected cable, but I do not see the interface board at the LSC rack

  4701   Thu May 12 09:00:23 2011 steveUpdateGeneraloptical table covers must be used

I found ITMX-ISCT and BS-ISCT ( IFO sensing-control table)  not covered this morning. Please do not leave tables open.

ELOG V3.1.3-