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ID Date Author Type Category Subjectup
  878   Mon Aug 25 12:13:49 2008 JenneUpdatePSLBroken PMC Servo Board
I broke the PMC servo board (on accident).

I was trying to measure the resistance of the extra resistor that someone put between the board and the HV OUT connector, since this is part of an RC filter (where C is the capacitance of the PZT on the PMC) that I need to know the values of as part of my mission to make a 14.6kHz notch for the PMC body mode. The resistance is 63.6k. I had to pull the board to get in to measure this resistance.

This resistor between the board and the center pin of the panel-mount HV OUT connector made a rigid connection between the board and the panel. When I was putting the board back in, I must have strained this connection enough that it broke. We don't have any of the same kind of resistor here at the 40m, so I'm waiting until after lunch to go to Wilson house and see if they've got any. The IFO is down until I get this sorted out.
  5299   Wed Aug 24 17:05:11 2011 JenneUpdateSUSBroken UL magnet on ITMX


The ITMX tower was shipped into the Bob's clean room to put the magnet back on. 

 Repair work is delayed.  I need the "pickle pickers" that hold the magnet+dumbbell in the gluing fixture, for gluing them to the optic.  Here at the 40m we have a full set of SOS gluing supplies, except for pickle pickers.  We had borrowed Betsy's from Hanford for about a year, but a few months ago I returned all of the supplies we had borrowed.  Betsy said she would find them in her lab, and overnight them to us.  Since the problem occurred so late in the day, they won't get shipped until tomorrow (Thursday), and won't arrive until Friday.

I also can't find our magnet-to-dumbbell gluing fixture, so I asked her to send us her one of those, as well. 

I have 2 options for fixing ITMX.  I'll write down the pros and cons for each, and we can make a decision over the next ~36 hours.


(#1) Remove dumbbell from optic.  Reglue magnet to dumbbell. Reglue magnet+dumbbell to optic.

(#2) Carefully clean dumbbell and magnet, without breaking dumbbell off of optic.  Glue magnet to dumbbell.


(#1) Guarantee that magnet and dumbbell are axially aligned.

(#2) Takes only 1 day of glue curing time.


(#1) Takes 2 days of glue curing time. (one for magnet to dumbbell, one for set to optic.)

(#2) Could have slight mismatch in axis of dumbbell and magnet.  Could accidentally drop a bit of acetone onto dumbbell-to-optic glue, which forces us into option 1, since this might destroy the integrity of the glue joint (this would take only the 2 days already required for option 1, it wouldn't force us to take 2+1=3 days).

  5302   Thu Aug 25 15:20:03 2011 JenneUpdateSUSBroken UL magnet on ITMX

Dmass just reminded me that the usual procedure is to bake the optics after the last gluing, before putting them into the chambers.  Does anyone have opinions on this? 

On the one hand, it's probably safer to do a vacuum bake, just to be sure.  On the other hand, even if we could use one of the ovens immediately, it's a 48 hour bake, plus cool down time.  But they're working on aLIGO cables, and might not have an oven for us for a while.  Thoughts?

  5305   Thu Aug 25 17:57:35 2011 SureshUpdateSUSBroken UL magnet on ITMX


Dmass just reminded me that the usual procedure is to bake the optics after the last gluing, before putting them into the chambers.  Does anyone have opinions on this? 

On the one hand, it's probably safer to do a vacuum bake, just to be sure.  On the other hand, even if we could use one of the ovens immediately, it's a 48 hour bake, plus cool down time.  But they're working on aLIGO cables, and might not have an oven for us for a while.  Thoughts?

I think we should follow the established procedure in full, even though it will cost us a few more days.  I dont think we should consider the vacuum bake as something "optional".  If the glue has any volatile components they could be deposited on the optic resulting in a change in the coating and consequently optical loss in the arm cavity.



  5306   Fri Aug 26 07:53:59 2011 steveUpdateSUSBroken UL magnet on ITMX


Dmass just reminded me that the usual procedure is to bake the optics after the last gluing, before putting them into the chambers.  Does anyone have opinions on this? 

On the one hand, it's probably safer to do a vacuum bake, just to be sure.  On the other hand, even if we could use one of the ovens immediately, it's a 48 hour bake, plus cool down time.  But they're working on aLIGO cables, and might not have an oven for us for a while.  Thoughts?

 Follow full procedure for full strength, minimum risk

  11242   Fri Apr 24 01:16:30 2015 JenneUpdateASCBroken Xass?

I ran the "off" script for the Xarm ASS, followed by the "on" script, and now the Xarm ASS doesn't work.  Usually we just run the freeze/unfreeze, but I ran the off/on scripts one time. 

Koji, if you have some time tomorrow, can you please look at it?  I am sorry to ask, but it would be very helpful if I could keep working on other things while the ASS is taken care of.

Steve, can you please find a cable that goes from the LSC rack to the IOO rack (1Y2 to 1X2), or lay a new one?  It must be one single long cable, without barrels sticking it together.  This will help me actuate on the Marconi using the LSC rack's DAC. 

Thank you!!

  11248   Sat Apr 25 03:32:45 2015 KojiUpdateASCBroken Xass?

I spent a day to fix the XARM ASS, but no real result. If the input of the 6th DOF servo is turned off, the other error signals are happy
to be squished to around their zeros. So this gives us some sort of alignment control. But obviously a particular combination of the
misalignment is left uncontrolled.

This 6th DOF uses BS to minimize the dither in ITMX yaw. I tired to use the other actuators but failed to have linear coupling between
the actuator and the sensor.

During the investigation, I compared TRX/TRY power spectra. TRX had a bump at 30Hz. Further investigation revealed that the POX/POY
had a big bump in the error signals. The POX/POY error signals between 10-100Hz were coherent. This means that this is coming from
the frequency noise stabilized with the MC. (Is this frequency noise level reasonable?)

The mysterious discovery was that the bump in the transmission exist only in TRX. How did the residual frequency noise cause
the intensity noise of the transmission? One way is the PDH offset.

Anyway, Rana pointed out that IMC WFS QPDs had large spot offsets. Rana went to the AS table and fixed the WFS spot centering.
This actually removed the bump in TRX although we still don't know the mechanism of this coupling.

The bump at 30Hz was removed. However, the ASS issue still remains.

  12342   Wed Jul 27 15:03:02 2016 sisyphusMetaphysicsSUSBroken wire

While tightening the bolts on the ETMX wire clamp, the wire broke. All four face magnets broke off. 

Fortunately, no pieces were lost.

  12343   Wed Jul 27 16:56:47 2016 ranaMetaphysicsSUSBroken wire

For the rest of this vent, at least, we need to start using the EQ stops more frequently. Whenever the suspension is being worked on clamp the optic. When you need it to be free back off the stops, but only by a few hundred microns - never more than a millimeter.

Best to take our time and use the stops often. With all the magnets being broken off, its not clear now how many partially cracked glue joints we have on dumbells which didn't completely fall off.

  2131   Wed Oct 21 17:12:30 2009 AlbertoUpdateelogBrowser context menu enabled on the Elog under HTM editing mode

On behalf of Steve and of the rest of the not-native-English community at the 40m willing to have their browser's spell checker working while editing the Elog, I fixed the Elog's feature that prevented Firefox' context menu (that one which pops up with a mouse right click) to work when using the HTML editing interface (FCKeditor).

That let also Firefox spell checker to get enabled.

To get the browser context menu just press CTRL right-clicking.

To make sure that the features works properly on your browser, you might have to fully clear the browser's cache.

Basically I modified the FCKeditor config file (/cvs/cds/caltech/elog/elog-2.7.5/scripts/fckeditor/fckconfig.js). I added this also to the elog section on our Wiki.

  16245   Wed Jul 14 16:19:44 2021 gautamUpdateGeneralBrrr

Since the repair work, the temperature is significantly cooler. Surprisingly, even at the vertex (to be more specific, inside the PSL enclosure, which for the time being is the only place where we have a logged temperature sensor, but this is not attributable to any change in the HEPA speed), the temperature is a good 3 deg C cooler than it was before the HVAC work (even though Koji's wind vane suggest the vents at the vertex were working). The setpoint for the entire lab was modified? What should the setpoint even be?


- I went to the south arm. There are two big vent ducts for the outlets and intakes. Both are not flowing the air.
  The current temp at 7pm was ~30degC. Max and min were 31degC and 18degC.

- Then I went to the vertex and the east arm. The outlets and intakes are flowing.

Attachment 1: rmTemp.pdf
  16246   Wed Jul 14 19:21:44 2021 KojiUpdateGeneralBrrr

Jordan reported on Jun 18, 2021:
"HVAC tech came today, and replaced the thermostat and a coolant tube in the AC unit. It is working now and he left the thermostat set to 68F, which was what the old one was set to."

  11310   Tue May 19 14:51:44 2015 ericqUpdateModern ControlBrushing up on Wiener Filtering

As part of preparing for the SURF projects this summer, I grabbed ~50 minutes of MCL and STS_1 data from early this morning to do a little MISO wiener filtering. It was pretty straightforward to use the misofw.m code to achieve an offline subtraction factor of ~10 from 1-3Hz. This isn't the best ever, but doesn't compare so unfavorably to older work, especially given that I did no prefiltering, and didn't use all that long of a data stretch.

Code and plot (but not data) is attached. 

Attachment 1: mclData.png
Attachment 2: mclWiener.zip
  11313   Tue May 19 17:53:38 2015 ranaUpdateModern ControlBrushing up on Wiener Filtering

Good to see that misofw.m is still alive and well. Todo:

  1. Apply weighting to the filter via time domain SOS prefiltering of the signals (see Jenne's code from the LLO Global FF paper)
  2. Consider using some of the MC SUSPOS signals. Its not strictly legal, but I wonder if its responsible for out noise below 1 Hz.
  3. Steve was in the midst of hooking up the Wilcoxones to get better subtraction at 5-15 Hz, but couldn't find cables. We need to hunt them down in W Bridge.
  4. Attach one of the medium or big Lings to the MC2 chamber platform and see if we can do this in hardware without driving the suspension. WE want to use a DAC channel (from where?) and pipe it to the Ling using a medium high current drive. Might start with the 50 Ohm output of the SR560 and later use a BUF634 ala Crackle coil driver.
  4418   Mon Mar 21 16:31:02 2011 steveUpdateSAFETYBryan Barr received safety training

Bryan Barr is visiting us from Glasgow for a month. He received 40m specific safety training on Friday.

  15991   Fri Apr 2 14:51:20 2021 AnchalUpdateSUSBug found, need to redo the balancing

Last run gave similar results as the quick run we did earlier. The code has been unable to strike out couplings with POS. We found the bug which is causing this. This was because the sampling rate of MC_F channel is different from the test-point channels used for PIT and YAW. Even though we were aware of it, we made an error in handling it while calculating CSD. Due to this, CSD calculation with POS data was performed by the code with zero padding which made it think that no PIT/YAW <-> POS coupling exist. blushHence our code was only able to fix PIT <-> YAW couplings.

We'll need to do another run with this bug fixed. I'll update this post with details of the new measurement.


  10754   Thu Dec 4 02:59:05 2014 ericqUpdateLSCBump in Darm Plant


After some housekeeping (ASS is wonky, alignment of X green beat was bad, tuning of demod angles, fm gains for REFL165), we were able to bring the PRFPMI up to arm powers of 8 very stably. 

We were keeping an eye on the DARM OLG, to make sure the gain was correct. We then saw a bump around 120Hz. Here is the bump. 


Changing CARM offset changes its amplitude. Maybe it's a DARM optical spring. It didn't occur to me until after we lost lock that we could have tweaked the DARM offset to move it around if this was the case. 

Unfortunately, due to some unexplained locklosses, we weren't able to get back into a state to measure this more... which is annoying. During that stable lock, Jenne stated that PRCL and DARM noises were looking particularly good. 

We may want to tweak the way we handle the transmission PD handoff; maybe we want to force the switch at a certain place in the carm_up script, so that we're not flipping back and forth during an IR handoff; I think this may have been responsible for a lock loss or two. 

  10755   Thu Dec 4 03:09:06 2014 JenneUpdateLSCBump in Darm Plant: Lockloss after measurement

We were sitting around arm powers of 6, and that loop measurement had finished.  I was about to go down to arm powers of 5ish, but we lost lock.  I'm not sure why.  There's some slow stuff going on in some of the servos, but nothing jumps out at me as a loop oscillation.  It does however kind of look like the PRMI lost lock just before the arm powers went down?  Perhaps this somehow triggered a lockloss?

The time is 1101721675.

Wide view plots:










We're stopping for tonight because ETMX is back to its lame-o jumping around.  I went in and squished the cables, but it's still happening.

Also, the FSS PC drive has been high the last few minutes (only starting after we quit for the night).  When the MC re-locks, it sounds like an ocean wave dying out as the noise goes down a little bit.  But, after a few minutes, it'll get mad again and unlock the MC.

Also, also, I noticed this on Monday with Diego, but the LSC-ALS[x,y] filter module gains sometimes mysteriously get set to zero.  WTF?  Eric and I have both independently checked, and we cannot find a single script in the scripts directory with the string "LSC-ALS", so we aren't deliberately changing those.  Does anyone know what might be going on here?

  4528   Fri Apr 15 02:18:50 2011 KojiUpdateLSCBunch of RF cables removed

While Kiwamu was working on the RF cabling at the LSC rack, I removed 80% of SMA cables which were not connected anywhere.
The rack is cleaner now, but not perfect yet. We need patch panels/strain relieving for heliaxes, cleaning up of the RF/LO cables, etc.

  13899   Wed May 30 23:57:08 2018 gautamUpdatePEMBurning smell in office area / control room

[koji, gautam]

We noticed quite a strong burning smell in the office area and control room ~20mins ago. We did a round of the bake lab, 40m VEA and the perimeter of the CES building, and saw nothing burning. But the smell persists inside the office area/control room (although it may be getting less noticeable). There is a whining noise coming from the fan belt on top of the office area. Anyways, since nothing seems to be burning down, we are not investigating further.

Steve [ 10am 5-31 ] we should always check partical count in IFO room

Service requested 


  6634   Wed May 9 14:32:31 2012 JenneUpdateCDSBurt restored

Den and Alex left things not-burt restored, and Den mentioned to me that it might need doing.

I burt restored all of our epics.snaps to the 1am today snapshot.  We lost a few hours of striptool trends on the projector, but now they're back (things like the BLRMS don't work if the filters aren't engaged on the PEM model, so it makes sense).

  10026   Wed Jun 11 14:41:11 2014 JenneUpdateSUSBurt restored c1scxepics

ETMX had default 1's for gains, 0's for matrix elements, etc., so I did a burt restore to May 25th, 2pm, which was a few days before the Crash.  It looks fine now.

  4046   Mon Dec 13 17:18:47 2010 josephbUpdateCDSBurt updates


Autoburt wouldn't restore settings for front ends on reboot

What was done:

First I moved the burt directory over to the new directory structure.

This involved moving /cvs/cds/caltech/burt/ to /opt/rtcds/caltech/c1/burt.

Then I updated the burt.cron file in the new location, /opt/rtcds/caltech/c1/burt/autoburt/.  This pointed to the new autoburt.pl script.

I created an autoburt directory in the /opt/rtcds/caltech/c1/scripts directory and placed the autoburt.pl script there.

I modified the autoburt.pl script so that it pointed to the new snapshot location.  I also modified it so it updates a directory called "latest" located in the /opt/rtcds/caltech/c1/burt/autoburt directory.  In there is a set of soft links to the latest autoburt backup.

Lastly, I edited the crontab on op340m (using crontab -e) to point to the new burt.cron file in the new location.

This was the easiest solution since the start script is just a simple bash script and I couldn't think of a quick and easy way to have it navigate the snapshots directory reliably.

I then modified the Makefile located in /opt/rtcds/caltech/c1/core/advLigoRTS/ which actually generates the start scripts, to point at the "latest" directory when doing restores.  Previously it had been pointing to /tmp/ which didn't really have anything in it.

So in the future, when building code, it should point to the correct snapshots now.  Using sed I modified all the existing start scripts to point to the latest directory when grabbing snapshots.


According to Keith directory documentation (see T1000248) , the burt restores should live in the individual target system directory i.e. /target/c1sus/burt, /target/c1lsc/burt, etc.  This is a distinctly different paradigm from what we've been using in the autoburt script, and would require a fairly extensive rewrite of that script to handle this properly.  For the moment I'm keeping the old style, everything in one directory by date.  It would probably be worth discussing if and how to move over to the new system.

  2459   Mon Dec 28 15:19:19 2009 AlbertoUpdateComputersBurtrestored to Dec 26 at 20:00

Since it wasn't sure whether all the front-ends had been restored after the bootfest, I burtrestored everything to Dec 26 at 20:00.

Always keep in mind that to burtrestore c1dcuepics, the snapshot file has to be modified by hand by moving the last quote up to the line before the last.

  3555   Thu Sep 9 18:53:56 2010 AlbertoConfigurationElectronicsBusby Box, Rai's Box, SR554 in the RF cabinet

I stored the Busby Box, the Rai's Box and the SR554 preamp in the RF cabinet down the Y arm.

  2286   Tue Nov 17 21:10:35 2009 ranaSummaryElectronicsBusby Low Noise Box: Photos and Upgrades


It looked like the Busby Low Noise Box had too much low frequency noise and so I upgraded it. Here is a photo of the inside - I have changed out the 0.8 uF AC coupling cap with a big, white, 20 uF one I found on Rob's desk.

The Busby Box is still working well. The 9V batteries have only run down to 7.8V. The original designer also put a spare AD743 (ultra low current FET amp) and a OP27 (best for ~kOhm source impedances) in there.

Here's the noise after the fix. There's no change in the DC noise, but the AC noise is much lower than before:


I think that the AC coupled noise is higher because we are seeing the current noise of the opamp. In the DC coupled case, the impedance to ground from the input pins of the opamp is very low and so the current noise is irrelevant.

The change I implemented, puts in a corner frequency of fc = 1/2/pi/R/C = 1/2/pi/10e3/20e-6 = 0.8 Hz.

Overall, the box is pretty good. Not great in terms of current noise and so it misses getting an A+. But its easily a solid A-.

  11293   Sat May 16 20:37:09 2015 ranaHowToCDSBypassing the CDSUTILS prefix issue

The CDSUTILS package has a feature where it substitutes in a C1 or H1 or L1 prefix depending upon what site you are at. The idea is that this should make code portable between LLO and LHO.

Here at the 40m, we have no need to do that, so its better for us to be able to copy and paste channel names directly from MEDM or whatever without having to remove the "C1:" from all over the place.

the way to do this on the command line is (in bash) to type:

export IFO=''

To make this easier on us, I have implemented this in our shared .bashrc so that its always the case. This might break some scripts which have been adapted to use the weird CDSUTILS convention, so beware and fix appropriately.

  11302   Mon May 18 16:56:12 2015 ericqHowToCDSBypassing the CDSUTILS prefix issue

export IFO=''

This makes things act weird:

controls@pianosa|MC 1> z avg 1 "C1:LSC-TRY_OUT"
IFO environment variable not specified.

  11304   Mon May 18 17:44:30 2015 ranaHowToCDSBypassing the CDSUTILS prefix issue

Too weird. I undid me changes. We'll have to make the C1: stuff work inside each python script.


export IFO=''

This makes things act weird:

controls@pianosa|MC 1> z avg 1 "C1:LSC-TRY_OUT"
IFO environment variable not specified.


  8672   Tue Jun 4 17:28:09 2013 AnnalisaUpdateLSCC1:ALS-TRY_OUT filter and green progress

 [Annalisa, Gautam, Rana]

I made the anti-whitening filter for the C1:ALS-TRY_OUT channel.

zpk [[150],[15],1] Hz

Now we can look at the picks of this signal to align the green into the cavity.

We already had some 00 flash, but a better alignment has to be done.


- put the shutter along the beam path

- check the polarization (we have a new PBS for visible)


Attachment 1: green.JPG
Attachment 2: QUAD1_1054358327.mp4
  8674   Tue Jun 4 21:50:23 2013 AnnalisaUpdateLSCC1:ALS-TRY_OUT filter and green progress


 [Annalisa, Gautam]

 The green beam alignment has been improved, so we see much more 00 bright flashing. We checked the polarization and the Ygreen shutter is back in place.

A mirror is already in place to steer the rejected beam from the green Faraday into a PD, tomorrow morning we'll put a lens and the PD to take the signal for PDH locking.


  8677   Wed Jun 5 14:01:37 2013 ranaUpdateLSCC1:ALS-TRY_OUT filter and green progress

The rejected beam from this Faraday comes out at a tiny, tiny angle and so its tough to pick it off without clipping the main beam.

Some care must be taken in setting this up - Steve may have some good ideas on what kind of mount can be placed so close to the beam.

Why did we ever order this terrible Faraday? Let's never get a Faraday with a tiny angle between the beams again.

  8680   Wed Jun 5 15:03:42 2013 AnnalisaUpdateLSCC1:ALS-TRY_OUT filter and green progress


The rejected beam from this Faraday comes out at a tiny, tiny angle and so its tough to pick it off without clipping the main beam.

Some care must be taken in setting this up - Steve may have some good ideas on what kind of mount can be placed so close to the beam.

Why did we ever order this terrible Faraday? Let's never get a Faraday with a tiny angle between the beams again.

The rejected beam from the Faraday is steered with a mirror into the PDA32A PD  and a 75mm fl lens is used to focus the beam into it.

The main beam is a few millimeters away from the mirror mount (maybe 2mm), and I think it should be fine as long as the main beam is not supposed to move.


Attachment 1: faraday_rejected_beam.JPG
  4961   Tue Jul 12 10:18:05 2011 JamieUpdateCDSC1:DAQ-FB0_C1???_STATUS indicators red, restored after controller restarts

Yesterday I found the C1:DAQ-FB0_C1???_STATUS lights to be red for the SUS, MCS, SCX, and SCY controllers.  I know this has something to do with model communication with the framebuilder, but I unfortunately don't remember exactly what it is.  I decided to try restarting the affected models to see if that cleared up the problem.  It did.  After restarting c1scx, c1scy, c1sus, and c1mcs everything came back up green.

We need some better documentation about what all of these status indicators mean.

  5006   Wed Jul 20 20:04:54 2011 JamieUpdateCDSC1:DAQ-FB0_C1XXX_STATUS sometimes unexplainably goes red

I have been noticing this happening occasionally, but I don't understand what is causing:


The channel in question above is C1:DAQ-FB0_C1SCX_STATUS.  This channel is (I believe) reporting some status of the front end model communication with the frame builder, but I'm not sure exactly what.

Usually this problem goes away when I restart the model or the frame builder, but it didn't work this time.  Tomorrow I will figure out what this channel means, why it's sporadically going red, and how to correct it.

  5901   Tue Nov 15 23:44:44 2011 MirkoUpdateCDSC1:LSC & C1:SUS restarted

Earlier this evening C1:LSC died then I hit the DAQ reload after adding an OAF channel to be recorded. No change to any model. Had to restart C1:SUS too. Reloaded burts from this morning 5am, except for C1:IOO, which I loaded from 16:07.

  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
  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.


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.


  1338   Thu Feb 26 00:36:53 2009 YoichiSummaryComputersC1:LSC-TRX_OUT broken (and fixed later).
Today, Kakeru tried to convert C1:LSC-TRX_OUT and C1:LSC-TRY_OUT to DAQ channels.
He edited C1LSC.ini in the chans/daq directory to add the channel but it did not work.
Then he reverted the file back to the original one.
But after we still could not access these channels from dataviewer nor tds tools.
We restarted daqd and tpman on fb40m, but the problem persisted. Even rebooting the whole fb40m did not help.
After inspecting the log file of daqd, it was clear that tpman was failing to create test points for those channels.
I rebooted c1daqawg and then restarted tpman and daqd on fb40m again.
This time, the problem went away.
  1292   Wed Feb 11 10:52:22 2009 YoichiConfigurationDAQC1:PEM-OSA_APTEMP and C1:PEM-OSA_SPTEMP disconnected

During the cleanup of the lab. Steve found a box with two BNCs going to the ICS DAQ interface and an unconnected D-SUB on the floor under the AP table.  It seemed like a temperature sensor.

The BNCs were connected to C1:PEM-OSA_APTEMP and C1:PEM-OSA_SPTEMP.

Steve removed the box from the floor. These channels can be now used as spare DAQ channels. I labeled those cables.

  950   Tue Sep 16 13:04:22 2008 YoichiConfigurationPEMC1:PSL-FSS_RMTEMP alarm level changed
At the request of Steve, I modified the HIGH value of C1:PSL-FSS_RMTEMP from 21.27 to 23.0.
The HIHI is set to 23.50.
  735   Thu Jul 24 19:29:26 2008 YoichiConfigurationPSLC1:PSL-STAT_FSS_NOM_C_GAIN is changed from 30 to -0.7
Koji, Yoichi

Since the light power going to the ref. cavity is now significantly increased (see Janne's elog later),
is changed from 30 to -0.7.
Otherwise, the MC did not lock.
  5666   Fri Oct 14 16:20:11 2011 ZachUpdateSUSC1:SUS-ETMX_SPDMon fixed

I offered to help Kiwamu with some of the 40m work. The first task was to figure out why the ETMX side OSEM monitor was so low, since we know that the depth is about right. It was showing ~0.13 V to the others' ~0.7 V.

TL,WR: There was a wire disconnected from the breakout panel on the side of the rack

I started by pulling the board out and checking to make sure that it was working properly. I injected a sine wave to the SIDE IN and found that it showed up in the signal coming out of the back (into the crate) just fine (see below). One strange thing I noticed while testing the board is that both inputs for each used channel of the MAX333 switches on the board are shorted to their respective outputs. That is, the switches seem to be open to BOTH 0 and 1 logic states. This seems counterintuitive, but perhaps there's something about how these work that I don't know.



Then I went about tracing the signal from the back of the crate to the breakout panel on the side of the rack. I opened it up, verified that the ribbon cable was transmitting correctly, and as I went to plug it back in I noticed that one of the wires---the correct one---had come completely undone.


The screw clamp appeared to be a bit finicky, as I had to loosen and tighten it a few times before it finally seemed to grab hold of the wire. It probably just wasn't tight in the first place and the wire was pulled out. Anyway, things are working now:


  5667   Fri Oct 14 18:38:41 2011 kiwamuUpdateSUSC1:SUS-ETMX_SPDMon fixed

Quote from #5666

 Anyway, things are working now:

 Good job ! Thank you so much

  11699   Mon Oct 19 16:16:01 2015 ericqUpdateCDSC1ALS crashes

Gautam was working on his digital frequency counter stuff when the c1als model crashed. I had trouble bringing it back until I realized that, for reasons unknown to me, the safe.snap file that the model looks for at boot had been deleted. (This file lives in /target/c1als/c1alsepics/burt). I copied over this morning's version from Chiara's local backup. 

At the sites, these files are under version control in the userapps svn repository, presumably symlinked into the target directory. We should definitely do something along these lines. 

  8028   Thu Feb 7 19:25:22 2013 yutaUpdateCDSC1ALS filters reloaded

Filters for C1ALS were all gone. So, I copied /opt/rtcds/caltech/c1/chans/C1GCV.txt and renamed it as C1ALS.txt.

I also fixed links in the medm screens; C1ALS.adl and C1ALS_COMPACT.adl.
I'm not sure what happened to C1SC{X,Y} screens.


I decided to rename the c1gcv model to be c1als.  This is in an ongoing effort to rename all the ALS stuff as ALS, and get rid of the various GC{V,X,Y} named stuff.


The above has been done.  Still todo:

  • FIX SCRIPTS!  There are almost certainly scripts that point to GC{V,X,Y} channels.  Those will have to be fixed as we come across them.
  • Fix the c1sc{x,y}/master/C1SC{X,Y}_GC{X,Y}_SLOW.adl screens.  I need to figure out a more consistent place for those screens.
  • Fix the C1ALS_COMPACT screen
  • ???



  5518   Thu Sep 22 13:56:56 2011 kiwamuUpdateASCC1ASS : status update

The output matrix in the C1ASS servo were coarsely readjusted and the servos seemed working.

However it is difficult to say the servo is very good or so-so,

because the ETMY suspension moves a lot and hence the cavity eigen axis moves a lot too.


(to do)

 + optimization of the ETMY oplevs and OSEM damping.
 + evaluation of the performance of the C1ASS with a good damping.


 Since we have installed the new mid-HV amplifier for the PZT1 mirror (#5450) it changed the response of the PZT1 (gains from EPICS to the actual angles).
Therefore the C1ASS output matrix needs be adapted to the new PZT1 response.
(What I have done)
  What I was measuring was a coupling from each PZT mirror to both beam angle and beam position by looking at the output from the LOCKINs.
So this measurement eventually gives us a nicely diagonalized output matrix by inverting the coupling.
However the measurement turned out to be difficult because the ETMY moved too much.
In fact the cavity eigen axis also moves and the fluctuation was larger than the intentionally introduced beam angle/translation offsets, which are for the coupling measurement.
 Instead of measuring the couplings, I put some numbers into the matrix based on a guess.
Since the PZT1 HV amp became weaker than that of PZT2, the elements in the output matrix should be amplified by some number.
Right now the PZT1 amp can drive the mirror in a range of -5 -30 V with EPICS range of +/-10 counts, and for PZT2 it is about 0 -150V with EPICS range of +/-5 counts.
So the difference of the responses in unit of V/counts is about 8.5.
The PZT1 elements in the matrix were multiplied by this number and I became able to close the servos.

Quote from #5455

  + Modification of C1ASS (Kiwamu)

  5543   Mon Sep 26 12:41:27 2011 kiwamuUpdateASCC1ASS : status update

Quote from #5518
(to do)
 + optimization of the ETMY oplevs and OSEM damping.
 + evaluation of the performance of the C1ASS with a good damping.

The servo for aligning the Y arm is working fine with the coarse gain coefficients.

However then I found the ASS_Xarm servo was not healthy.

So the next step is to refine the X arm servo in C1ASS.


(some notes)

  + With the ETMY oplev the Y arm became quieter after we recovered the oplev whitening filter (#5523)

  + The Y arm alignment scripts can be run from the usual C1IFO_CONFIGURE screen.

   It will servo the spot positions on ITMY and ETMY, and align the input beam pointing. It brings the Y arm power to about 1.

 + The X arm servo is doing something funny. It doesn't bring the arm power up to 1.

   I thought the X arm didn't need any modifications because the X arm servo doesn't include PZT1 and PZT2.

   So it maybe a simple bug (for example, some switches are disable and so on)


  5578   Fri Sep 30 01:18:39 2011 kiwamuUpdateASCC1ASS : status update

Now the C1ASS servos are working fine.

However at the end of the scripts sometimes it changes the DC force (e.g. C1:SUS-ITMX_PIT_COMM and so on) by a wrong amount.

So for this bug, it misaligns the suspensions a lot. I will take a look at the script tomorrow.

Quote from #5543

However then I found the ASS_Xarm servo was not healthy.

  15285   Thu Mar 26 22:31:34 2020 YehonathanUpdateCDSC1AUXEY wiring + channel list

I have made a wiring + channel list that need to be included in the new C!AUXEY Acromag.

It was mostly copied from C1AUXEX

I ignored the IPANG channels since it is going to be removed from the table.

ELOG V3.1.3-