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ID Date Author Type Category Subjectup
  13925   Thu Jun 7 12:20:53 2018 gautamUpdateCDSslow machine bootfest

FSS slow wasn't running so PSL PZT voltage was swinging around a lot. Reason was that was c1psl unresponsive. I keyed the crate, now it's okay. Now ITMX is stuck - Johannes just told be about an un-elogged c1susaux reboot. Seems that ITMX got stuck at ~4:30pm yesterday PT. After some shaking, the optic was loosened. Please follow the procedure in future and if you do a reboot, please elog it and verify that the optic didn't get stuck.

Attachment 1: ITMX_stuck.png
ITMX_stuck.png
  13410   Mon Nov 6 11:15:43 2017 gautamUpdateCDSslow machine bootfest + IFO re-alignment

Eurocrate key turning reboots today morning for and c1susaux, c1auxex and c1auxey. Usual precautions were taken to minimize risk of ITMX getting stuck.

The IFO hasn't been aligned in ~1week, so I recovered arm and PRM alignment by locking individual arms and also PRMI on carrier. I will try recovering DRMI locking in the evening.

As far as MC1 glitching is concerned, there hasn't been any major one (i.e. one in which MC1 is kicked by such a large amount that the autolocker can't lock the IMC) for the past 2 months - but the MC WFS offsets are an indication of when smaller glitches have taken place, and there were large DC offsets on the MC WFS servo outputs, which I offloaded to the DC MC suspension sliders using the MC WFS relief script.

I'd like for the save-restore routine that runs when the slow machines reboot to set the watchdog state default to OFF (currently, after a key-turning reboot, the watchdogs are enabled by default), but I'm not really sure how this whole system works. The relevant files seem to be in the directory /cvs/cds/caltech/target/c1susaux. There is a script in there called startup.cmd, which seems to be the initialization script that runs when the slow machine is rebooted. But looking at this file, it is not clear to me where the default values are loaded from? There are a few "saverestore" files in this directory as well:

  • saverestore.sav
  • saverestore.savB
  • saverestore.sav.bu
  • saverestore.req

Are the "default" channel values loaded from one of these?

  13408   Mon Oct 30 11:15:02 2017 gautamUpdateCDSslow machine bootfest + vacuum snafu

Eurocrate key turning reboots today morning for c1psl and c1aux.c1auxex and c1auxey are also down but I didn't bother keying them for now. PSL FSS slow loop is now active again (its inactivity was what prompted me to check status of the slow machines).

Note that the EPCIS channels for PSL shutter are hosted on c1aux.But looks like the slow machine became unresponsive at some point during the weekend, so plotting the trend data for the PSL shutter channel would have you believe that the PSL shutter was open all the time. But the MC_REFL DC channel tells a different story - it suggests that the PSL shutter was closed at ~4AM on Sunday, presumably by the vacuum interlock system. I wonder:

  1. How does the vacuum interlock close the PSL shutter? Is there a non-EPICS channel path? Because if the slow machine happens to be unresponsive when the interlock wants to close the PSL shutter via EPICS commands, it will be unable to. The fact that the PSL shutter did close suggests that there is indeed another path.
  2. We should add some feature to the vacuum interlock (if it doesn't already exist) such that the PSL shutter isn't accidentally re-opened until any vacuum related issues are resolved. Steve was immediately able to identify that the problem was vacuum related, but I think I would have just re-opened the PSL shutter thinking that the issue was slow computer related.
  3138   Tue Jun 29 17:10:49 2010 steve, ranaUpdateVACslow pumpdown started

The folding crane was fixed and tested this morning by the NNN rigging company. Pictures will be posted by Steve in the morning.

Afterwards, the ITM-east door was installed, jam-nuts checked. No high voltage was on for the in-vac PZTs.

The annulus spaces were roughed down to 350mTorr by Roughing Pump RP1. For this operation, we removed the low flow valve from the RP1 line.

After the spaces came down to ~400 mTorr, we closed their individual valves.

Warning: The VABSSC1 and VABSSC0 valves are incorrect and misleadingly drawn on the Vacuum overview screen.

We then:

  1. Closed V6 (valve between RP1 and the annulus line).
  2. Turned off RP1 from the MEDM screen.
  3. Installed the soft -starting butterfly valve.
  4. Turned on RP1.
  5. Opened V3.
  6. Closed VV1 (at the last minute - this is a vent valve and must be checked before each pumpdown)
  7. and pumpdown was started with a 3/4 turn opening of manual valve RV1.

Our idea is to have a much slower pumpdown this time than the last time when we had a hurricane kick up the dust. Looks like it worked, but next time we should do only 1/2 turn.

  3140   Tue Jun 29 23:49:18 2010 steve, ranaUpdateVACslow pumpdown started

Untitled.png

The pumpdown started at 4 PM (2300 UTC). At 10 PM, we (Jenne, Jan, and I) opened up the RV1 valve to full open. That's the second inflection point in the plot.

  3141   Wed Jun 30 00:45:26 2010 ranaUpdateVACslow pumpdown stopped for the night

As per Steve's instructions, at 12:43 AM, I used the following steps to stop the pumpdown until the morning:

  1. Close RV1 using the 'steering-wheel' wrench.
  2. Close V3.
  3. Turn OFF RP1.
  4. Disconnect RP1 hose at the plastic disconnect attached to the slow-start throttle valve.
  4089   Wed Dec 22 17:24:50 2010 steveConfigurationVACslow pumpdown at 12 hours

We have reached 200 Torr at 12 hours of slow pumping speed. Kiwamu stopped the pumping for 11 hrs last night .and I restarted it this morning.

Now RV1 is fully open with butterfly valve in place  and the second roughing  pump RP3 was just turned on.

 

How to stop pumping:

1,  close RV1 manual valve with torque wheel

2, close V3

3, turn off roughing pumps RP1 & RP3

4, disconnect metal hose connection to butterfly valve

Attachment 1: slowpd12h.jpg
slowpd12h.jpg
  4094   Thu Dec 23 13:30:09 2010 steveConfigurationVACslow pumpdown complete

The pump down continued this morning by the removal of the butterfly valve. Two roughing pumps were used to reach 500 mTorr

The Maglev monitoring MEDM screen "Rotating" indicator is not working. It is on all times. Please look at Maglev controller monitor for real information.

Pump down is completed.           

Configuration: vacuum normal after 86 days at atm               CC1 = 1e-5 Torr                  

                      IFO is hungry for light (and maybe some goulash with a little paprikash too)

Attachment 1: slow2dpd.jpg
slow2dpd.jpg
  3148   Wed Jun 30 15:24:04 2010 steve,kiwamuUpdateVACslow pumpdown copmlete

Quote:

Untitled.png

The pumpdown started at 4 PM (2300 UTC). At 10 PM, we (Jenne, Jan, and I) opened up the RV1 valve to full open. That's the second inflection point in the plot.

 Atm 2 is showing the butterfly valve that closes down down the orifice at higher pressure to slow down the pumping speed.

 See elog entry #2573

 

Attachment 1: slowpd.jpg
slowpd.jpg
Attachment 2: butterfly.JPG
butterfly.JPG
  3331   Fri Jul 30 09:55:34 2010 steveConfigurationVACslow pumpdown has started

Bob and Steve closed BS chamber with the help of the manual Genie lift and the pump down started. The PSL shutter was closed and manual block was placed in the beam path. High voltage power supplies were checked to be off.

Pumping speed ~ 1 Torr/min was achieved at  1/8 of a turn opened roughing valve RV1

Attachment 1: slowpd5hr.jpg
slowpd5hr.jpg
  2573   Fri Feb 5 11:01:49 2010 steveConfigurationVACslow pumpdown valve

I have installed a slow start throttle valve in front of V3  This spring loaded valve will cut down on the flow at high pressures. There will be no more sand storme

and static built-up during pump down.

Attachment 1: slow.JPG
slow.JPG
  3248   Tue Jul 20 08:04:31 2010 steveConfigurationVACslow vent has started

The PSL shutter was closed. The beam path  blocked two places. High voltage power supplies to IOO and OMC PZT were checked to be off. Oplevs are off. 

The south arm green cavity was misaligned yesterday

We would like to keep the vent speed at 1 torr / min. I'm venting with N2 now up to 25 PSI. We have 3 cylinder  of instrument grade air inside the lab. Additional supply will arrive later. It can be as late as 1pm

  3611   Mon Sep 27 08:59:50 2010 steveConfigurationVACslow vent has started

Blocked PSL output beam  into IFO

Checked: HV at IOO & OMC are off, jam nuts in position,

Closed V1 and VM3, opened VV1 to N2 regulator

We are venting at 1 Torr/min rate

  6836   Wed Jun 20 00:02:16 2012 yutaUpdateGreen Lockingslower scan using phase tracking ALS

For those of you who want to see plots from slower scan.

YarmScan20120619.png

  14182   Fri Aug 24 08:04:37 2018 SteveUpdateGeneralsmall earth quake

 

 

Attachment 1: small_EQ.png
small_EQ.png
  14185   Mon Aug 27 09:14:45 2018 SteveUpdatePEMsmall earth quakes

Small earth quakes and suspensions. Which one is the most free and most sensitive: ITMX

 

Attachment 1: small_EQs_vs_SUSs.png
small_EQs_vs_SUSs.png
  7950   Mon Jan 28 21:36:44 2013 tall guyFrogsGeneralsmall people on notice

If I catch anyone putting small booties into the large bootie bin, I will make said person eat small booties.

  13047   Wed Jun 7 11:32:56 2017 SteveUpdateVACsmooth vac reboot

Gautam and Steve,

 

The medm monitor & vac control screens were totally blank since ~ May 24, 2017    Experienced vacuum knowledge is required for this job.

IDENTIFY valve configuration:

                        How to confirm valve configuration when all vac mons are blank?  Each valve has a manual-mechanical position indicator. Look at pressure readings and turbo pump controllers. VAC NORMAL configuration was confirmed based on these information.

Preparation: disconnect valves ( disconnect meaning: valve closes and stays paralized ) in this sequence VC2, VC1 power, VA6, V5, V4 & V1 power,      at ifo pressure 7.3E-6 Torr-it  ( it  = InstruTech cold cathode gauge )

                            This gauge is independent from all other rack  mounted   instrumentation and it is still not logged.

                            Switching to this valve configuration with disconnected valves will insure NOT  venting of the vacuum envelope by accidental glitching voltage drop or computer malfunction.

RESET  v1Vac1 .........in 2-3 minutes........ ( v1Vac1 - 2 )  the vac control screen started reading pressures & position

                    Connected cables to valves (meaning: valve will open if it was open before it was disconnected and it will be control able from computer ) in the following order: V4, V1 power, V5, VA6, VC2 & VC1 power,      at ifo 2E-5 Torr-it.....

                     ....vac configuration is reading VAC NORMAL,

                     ifo 7.4E-6 Torr-it

We have to hook up the it-cold cathode gauge to be monitored - logged !  this should be the substitute for the out of order CC1 pressure gauge.

Attachment 1: vac_reboot.png
vac_reboot.png
  16237   Fri Jul 2 12:42:56 2021 Anchal, Paco, GautamSummaryLSCsnap file changed for MICH

We corrected the MICH locking snap file C1configure_MI.req and saved an updated C1configure_MI.snap. Now the 'Restore MICH' script in IFO_CONFIGURE>!MICH>Restore MICH works. The corrections included adding the correct rows of PD_DOF matrices to be at the right settings (use AS55 as error signal). The MICH_A_GAIN and MICH_B_GAIN needed to be saved as well.

We also were able to get to PRMI SB resonance. PRM was misalgined earlier from optimal position and after some manual aligning, we were able to get it to lock just by hitting IFO_CONFIGURE>!PRMI>Restore PRMI SB (3f).

  1649   Wed Jun 3 18:55:27 2009 ranaUpdateCOCsnapshot of upgrade layout
Attachment 1: layout.png
layout.png
  131   Wed Nov 28 16:18:15 2007 AlbertoMetaphysicsEnvironmentso clean you can eat on it
I tidied up the desks in the lab, brought the Spectrum Analyzers back to the Salumeria (you don't want to know about that), sorted a lot of stuff and boxed up what I didn't know (you can find it in a couple of carton boxes on the table).
The blackmail with the pie might not work next time.
Please, preserve the common sort.


Alberto
Attachment 1: DSC_0180.JPG
DSC_0180.JPG
Attachment 2: DSC_0181.JPG
DSC_0181.JPG
  5734   Tue Oct 25 11:48:02 2011 KatrinHowToElectronicssolder tiny smd op amps

Yesterday, I had the great pleasure to solder a tiny 4 x 4 mm op amp with 16 legs (AD8336).

I figured out that the best and fastest way to do it is

  1. to put solder with the soldering iron on every contact of the electronic board (top side)
  2. heat the bottom side of the electronic board with a heat gun
  3. use a needle to test if the solder is melted
  4. if it is melted place the op amp on the electronic board
  5. apply some vertical force on the op amp for proper contact and heat for 1 to 2 more minutes
  6. done

 

  2768   Mon Apr 5 10:33:12 2010 AlbertoOmnistructureElectronicssoldering iron broken

This morning the pencil soldering iron of our Weller WD2000M Soldering Station suddenly stopped working and got cold after I turned the station on. The unit's display is showing a message that says "TIP". i checked out the manual, but it doesn't say anything about that. I don't know what it means. Perhaps burned tip?

Before asking Steve to buy a new one, I emailed Weller about the problem.

  2770   Mon Apr 5 13:07:36 2010 JenneOmnistructureElectronicssoldering iron broken

Quote:

This morning the pencil soldering iron of our Weller WD2000M Soldering Station suddenly stopped working and got cold after I turned the station on. The unit's display is showing a message that says "TIP". i checked out the manual, but it doesn't say anything about that. I don't know what it means. Perhaps burned tip?

Before asking Steve to buy a new one, I emailed Weller about the problem.

 There should be a supply of extra tips in the Blue Spinny Cabiney (I can never remember it's French name....)  The drawer is something like the top row of one of the bottom sets of drawers.  You can pick the shape of tip you want, and stick it in.

  2771   Mon Apr 5 13:20:16 2010 KojiOmnistructureElectronicssoldering iron broken

Albeto and Koji

We took the tip replacement from the blue tower.

I am looking at http://www.cooperhandtools.com/brands/weller/ for ordering the tips.

The burnt one seems to be "0054460699: RT6 Round Sloped Tip Cartridge for WMRP Pencil" We will buy one.

The replaced one is "0054460299: RT2 Fine Point Cartridge for WMRP Pencil" We will buy two.

I like to try this: "0054460999: RT9 Chisel Tip Cartridge for WMRP Pencil" We will buy one.

Quote:

This morning the pencil soldering iron of our Weller WD2000M Soldering Station suddenly stopped working and got cold after I turned the station on. The unit's display is showing a message that says "TIP". i checked out the manual, but it doesn't say anything about that. I don't know what it means. Perhaps burned tip?

Before asking Steve to buy a new one, I emailed Weller about the problem.

 

Attachment 1: weller_tips.jpg
weller_tips.jpg
  11570   Fri Sep 4 00:58:29 2015 ranaUpdateCDSsoldering the Generic Pentek interface board

Q and Ignacio were taking a second look at the Pentek interface board which we're using to acquire the POP QPD, ALS trans, and MCF/MCL channels. It has a differential intput, two jumper able whitening stages inside and some low pass filtering.

I noticed that each channel has a 1.5 kHz pole associate with each 150:15 whitening stage. It also has 2 2nd order Butterworth low pass at 800 Hz. Also there's a RF filter on the front end. We don't need all that low passing, so I started modifying the filters. Tonight I moved the 800 Hz poles to 8000 Hz. Tomorrow we'll move the others if Steve can find us enough (> 16) 1 nF SMD caps (1206 NPO).

After this those signals ought to have less phase lag and more signal above 1 kHz. Since the ADC is running at 64 kHz, we don't need any analog filtering below 8 kHz.

  3693   Mon Oct 11 22:45:16 2010 kiwamuUpdateComputerssolid works 2010 installed

solidworks.PNG

Solid works 2010 was installed to m3, an windows machine in the control room.

Have fun !

  4981   Mon Jul 18 10:24:48 2011 steveHowToGeneralsolvent bottles for cleaning optics

Each bottle has matched seals. They are not interchangeable.

It is critical that the solvent do not reach the rubber bulb. Practice with the pipet.

In case of solvent touching the suction bulb: do not let the solvent go back into the bottle! Remove bulb, let it dry out and rinse pipet.

It is essential that the solvent bottle must be rinsed and refilled if it's content met with the rubber bulb.

Use glass syringe with SS needle in critical application: Hamilton ~0.1 ml

Attachment 1: P1080090.JPG
P1080090.JPG
  9940   Mon May 12 10:42:01 2014 ranaUpdateSUSsome Arm maintenance

I ran the ASS/ADS for the arms because the X-arm was way out. There was also some problem with its locking due to bad ramps in FM2. I copied over the filters from YARM and then adjusted some of the ramps and thresh trigs in the filter file until the transients in POX got smaller. Basically, you should not really be ramping on Integrators. Secondly, we should do some testing when adjusting the filter parameters.

I hooked up the 4395 to the MC servo board OUT2 so that we can monitor the error point when the PCDRIVE goes nuts.

  5561   Wed Sep 28 02:42:04 2011 kiwamuUpdateCDSsome DAQ channel lost in c1sus : fb, c1sus and c1pem restarted

Somehow some DAQ channels for C1SUS have disappeared from the DAQ channel list.

Indeed there are only a few DAQ channels listed in the C1SUS.ini file.

I ran the activateDQ.py and restarted daqd.

Everything looks okay.  C1SUS and C1PEM were restarted because they became frozen.

  5621   Wed Oct 5 14:18:09 2011 kiwamuUpdateCDSsome DAQ channel lost in c1sus : fb, c1sus and c1pem restarted

I found again the ini files had been refreshed.

I ran the activateDQ.py script (link to the script wiki page) and restarted the daqd process on fb.

The activateDQ.py script should be included into the recompile or rebuild scripts so that we don't have to run the script everytime by hands.

I am going to add this topic on the CDS todo list (wiki page).

Quote from #5561

Somehow some DAQ channels for C1SUS have disappeared from the DAQ channel list.

 

  5515   Thu Sep 22 11:49:05 2011 kiwamuUpdateLSCsome LSC scripts don't run on pianosa

Found some LSC scripts didn't run on pianosa. Particularly all the scripts on the C1:IFO_CONFIGURE screen don't run.

They need to be fixed.

  8468   Mon Apr 22 11:26:25 2013 KojiConfigurationCDSsome RT processes restarted

When I came to the 40m, I found most of the FB signals are dead.

The suspensions were not dumped but not too much excited. Use watchdog switches to cut off the coil actuators.

Restarted mxstream from the CDS_FE_STATUS screen. The c1lsc processes got fine. But the FB indicators for c1sus, c1ioo, c1iscex/y are still red.

Sshed into c1sus/ioo, run rtcds restart all . This made them came back under control.

Same treatment for c2iscex and c1iscey. This made c1sus stall again. Also c1iscey did not come back.

At this point I decided to kill all of the rt processes on c1sus/c1ioo/c1iscex/c1iscey to avoid interference between them.
And started to restart from the end machines.

c1iscex did not come back by rtcds restart all.
Run lsmod on c1iscey and found c1x05 persisted stay on the kernel. rmmod did not remove the c1x05 module.
Run software reboot of c1iscey. => c1iscey came back online.

c1iscey did not come back by rtcds restart all.
Run software reboot of c1iscex. => c1iscex came back online.

c1ioo just came back by rtcds restart all.

c1sus did not come back by rtcds restart all.
Run software reboot of c1sus => c1sus came back online.

This series of restarting made the fb connections of some of the c1lsc processes screwed up.
Run the following restarting commands => all of the process are running with FB connection.
rtcds restart c1sup
rtcds restart c1ass
rtcds restart c1lsc

Enable damping loops by reverting the watchdog switches.

All of the FE status are green except for the c1rfm bit 2 (GE FANUC RFM CARD 0).

  6055   Wed Nov 30 22:09:20 2011 ZachUpdateRF Systemsome final EOM stabilization efforts

First, things that were done:

  • I was troubled by the odd-looking noise in the EOM temperature signal, so I investigated the circuit with a probe and found that there was quite a bit of line pickup, which I traced to the wires going to and from the RTD (if I placed a dummy resistor directly on the board, it went down markedly).
    • I put a 3-Hz RC LPF between the AD620 and the driver input buffer, which reduced the line noise significantly
    • The error signal looks much cleaner and there are no longer strong peaks in the error spectrum at ~1+ Hz and harmonics
  • I had tried earlier to increase the gain of the servo at the driver input stage. It seemed to stay stable. Since I knew the error signal  with the loop closed was at the level of the ADC noise, I decided to push my luck with increasing the servo gain and juice up the AD620 gain from 100 to 990.
    • The servo stayed stable and the error signal level is now manageable.

Things that I noticed:

  • With the latest increase in gain, I measured that the error signal was suppressed with the loop closed (the suppression is below ~0.1 Hz, and the reason that the high-frequency level is different is because it has been amplified above the ADC noise by the time of the second trace).

 EOM_temp_stab_and_unstab_new_11_30_11.pdf

  • Despite the above, the Stochmon signals remained unchanged no matter what I did. I noticed that the Stochmon signals, too, were fluctuating basically at bit-level. I terminated the 11-MHz signal and compared it to the normal level---it is not exactly the same, but only a factor of 2-3 lower, which is not great. Of course, the RMS detector is logarithmic, but I think we still want the dark noise to be at least an order of magnitude lower here.
    • I tried to amplify the signal with an SR560, but since the DC level is supposed to be ~1-2 V, I could only get about 2x gain---not enough.

 11MHz_wandwo_ctrl_and_adc_noise_11_30_11.pdf

Conclusion

I think there are two things that could be happening here, given the above information:

  1. We are limited by the noise of the temperature sensing circuit, which would explain why the in-loop error signal is suppressed while the RAM levels appear not to be. This should be easy enough to test (though there's not enough time right now) with an out-of-loop sensor.
  2. The RAM is not dominated by temperature noise here. With the loop open, one would expect to see coherence between the RAM signal and the temperature sensor, if indeed one was the cause of the other. Instead, we see that---while the 11- and 55-MHz signals ARE pretty coherent with each other---there is no appreciable coherence between the temperature and the Stochmon signal.
  11601   Tue Sep 15 18:35:21 2015 ericqSummaryLSCsome further notes

About the analog CARM control with ALS:

We're looking at using a Sigg designed remotely switchable delay line box on the currently undelayed side of the ALS DFD beat. For a beat frequency of 50MHz, one cycle is 20ns, this thing has 24ns total delay capability, so we should be able to get pretty close to a zero crossing of the analog I or Q outputs of the demod board. This can be used as IN2 for the common mode board. 

Gautam is testing the functionality of the delay and switching, and should post a link to the DCC page of the schematic. Rana and Koji have been discussing the implementation of the remote switching (RCG vs. VME). 

I spent some time this afternoon trying to lock the X arm in this way, but instead of at IR resonance, just wherever the I output of the DFD had a zero crossing. However, I didn't give enough thought to the loop shapes; Koji helped me think it through. Tomorrow, I'll make a little pomona box to go before the CM IN2 that will give the ALS loop shape a pole where we expect the CARM coupled cavity pole to be (~120Hz), so that the REFL11 and ALS signals have a similar shape when we're trying to transition. 

The common mode board does have a filter for this kind of thing for single arm tests, but puts in a zero as well, as it expects the single arm pole, which isn't present in the ALS sensing, so maybe I'll whip up something appropriate for this, too. 

  11609   Thu Sep 17 03:48:10 2015 ericqSummaryLSCsome further notes

Something odd is happening with the CM board. Measuring from either input to OUT1 (the "slow output") shows a nice flat response up until many 10s of kHz. 

However, when I connect my idependently confirmed 120Hz LPF to either input, the pole frequency gets moved up to ~360Hz and the DC gain falls some 10dB. This happens regardless if the input is used or not, I saw this shape at a tee on the output of the LPF when the other leg of the tee was connected to a CM board input. 

This has sabotaged my high bandwidth ALS efforts. I will investigate the board's input situation tomorrow.

  14826   Sun Aug 4 14:39:41 2019 gautamUpdateGeneralsome lab activity
  1. Unresponsive c1psl, c1iool0, c1auxey and c1iscaux VME crates were keyed.
  2. c1psl channels were burt-restored, did a burtrestore, and re-locked the PMC. Tweaked the pointing into the PMC on the PSL table to increase the PMC transmission from ~0.69 to ~0.71.
  3. Re-locked IMC. Ran WFS offset script to relieve the ~100 DAC counts (~10 urad) DC offset from the WFS servos to the IMC suspensions (a serious calibration of this into physical units should be made part of the planned 40m WFS activity). Now that I think about it, since we change the IMC alignment to match the input beam alignment, some post-IMC clipping could modulate the power incident on the ITMs, which is a source of error for the arm cavity loss determination using DC reflection. We need a better normalizing data stream than the IMC transmission.
  4. The IFO_OVEREVIEW medm screen was modified such that the threshold for the PMC transmitted beam to be visible was lowered from 0.7 to 0.6, so that now there is a continuous beam line from the NPRO to the PRM when the IMC is locked even when the PMC transmission degrades by 5% due to thermally driven pointing drifts on the PSL table.
  5. The wmctrl utility on pianosa wasn't working so well, I wasn't able to use my usual locking MEDM autoconfig scripts. Turned out to be due to a zombie MEDM window which I killed with xkill, now it is working okay again.
  6. The misaligned XARM was re-aligned and the loss measuring PDA520 at the AS port was removed from the beam path (mainly to avoid ADC saturations the fringing Michelson will cause).
  7. I noticed that the ETMX Oplev HeNe SUM level has degraded to ~50% of its power level from 200 days ago [Attachment #1], may need a new HeNe here soon. @Chub, do we have spare HeNes in stock?

I want to collect some data with the arms locked to investigate the possibility/usefullness of having seismic feedforward implemented for the arms (it is already known to help the IMC length and PRC angular stability at low frequencies). To facilitate diagnostics I modified the file /users/Templates/Seismic/Seismic_vs_TRXTRYandMC.xml to have the correct channel names in light of Lydia's channel name changes in 2016. Looking at the coherence data, the alignment of the cartesian coordinate system of the Seismometers at the ends and the global interferometer coordinate system can be improved.

I don't know if for the MISO filter design if there is any difference in using TRX/TRY as the target, or the arm length control signal.

Data collection started at 1249018179. I've setup a script running in a tmux shell to turn off the LSC enable in 2 hours.

Attachment 1: ETMX_OL.png
ETMX_OL.png
Attachment 2: Seismic_TRXTRYandMC_4Aug2019.pdf
Seismic_TRXTRYandMC_4Aug2019.pdf
  4070   Sat Dec 18 01:17:04 2010 kiwamuUpdateIOOsome more alignments

 [Koji and Kiwamu]

 We did some more vacuum works today. It is getting ready to pump down.

 (what we did) 

 - alignment of the POY mirrors. Now the beam is coming out from the ITMY chamber successfully

  - leveling of the tables (except for the IOO and OMC chamber)

  - realigned the beam axis down to the Y arm because the leveling of the BS table changed the alignments.

 - installed IP_POS mirrors

 - aligned the green beam and made it overlap with IR beam path.

 - repositioned green steering mirrors since one of them are too close to the dark beam path

 - aligned everything.

  4189   Sat Jan 22 02:11:09 2011 kiwamuUpdateGreen Lockingsome more progress

[Rana, Suresh, Kiwanu]

 We did the following things:

   *  taking the VCO stability data from the error signal instead of the feedback

   *  tried calibrating the signal but confused

   *  increased the modulation depth of the green end PDH.

--

 We found that a cable coming out from the VCO box was quite touchy. This cable was used for taking the feedback signal.

When we touched the cable it made a big noise in the feedback. So we decided to remove the cable and take the signal from the error point (i.e. just after the mixer and the LPF.)

In order to correct that signal to the one in terms of the feedback signal, we put a digital filter which is exactly the same as that of the PLL (pole at 1.5 Hz, zero at 40 Hz, G=1) .

However for some reasons the signal shown in the digital side looked completely mis-calibrated by ~ 100. We have no idea what is going on.

Anyway we are taking the data over tonight because we can correct the signal later. The 2nd round data started from AM1:40

  4190   Sat Jan 22 02:23:26 2011 KojiUpdateGreen Lockingsome more progress

What is the point to use the error instead of the feedback? It does not make sense to me.

If the cable is flaky why we don't solder it on the circuit? Why we don't put a buffer just after the test point?

It does not make sense to obtain the error signal in order to estimate the freeruning noise without the precise loop characterization.
(i.e. THE FEEDBACK LOOP TRINITY: Spectrum, Openloop, Calibration)

RA: I agree that feedback would be better because we could use it without much calibration. But the only difference between the "error signal" and the "feedback signal" in this case is a 1.6:40 pole:zero stage with DC gain of 0 dB. So we can't actually use either one without calibration and the gain between these two places is almost the same so they are both equally bad for the SNR of the measurement. I think that Suresh and Kiwamu are diligently reading about PLLs and will have a more quantitative result on Monday afternoon.

 

  5609   Mon Oct 3 23:52:49 2011 kiwamuUpdateCDSsome more tests for the Dolphin

[Koji / Kiwamu]

 We did several tests to figure out what could be a source of the computer issue.

The Dolphin switch box looks suspicious, but not 100% sure.

 

(what we did)

 + Removed the pciRfm sentence from the c1x04 model to disable the Dolphin connection in the software.

 + Found no difference in the Makefile, which is supposed to comment out the Dolphin connection sentences.

   ==> So we had to edit the Makefile by ourselves

 + Did a hand-comilpe by editing the Makefile and running a make command.

 + Restarted the c1x04 process and it ran wihtout problems.

   ==> the Dolphin connection was somehow preventing the c1x04 process from runnning.

 +  Unplugged the Dolphin cables on the back side of the Dolphin box and re-plug them to other ports.

   ==> didn't improve the issue.

 + During those tests, c1lsc frequently became frozen. We disabled the automatic-start of c1lsc, c1ass, c1oaf by editting rtsystab.

  ==> after the test we reverted it.

 + We reverted all the things to the previous configuration.

  14076   Tue Jul 17 12:46:28 2018 ranaUpdateGeneralsome notes from yesterday

For the EY, instead of balancing the table, I just moved the weight approximately so that the ETMY OSEMS were at half light, but didn't check the level since ETMY is the only optic.

 

Some notes on OMC/AS work (Aaron/Gautam can amend/correct):

- Beam is now well centered in OMC MMT. Hits input coupling mirror and cleanly exits the vacuum to the AS table.

- Didn't see much on OMC trans, but PDs are good based on flashlight test.

- just before closing, re-aligned beam in yaw so that it gets close to the east screw on the input coupler. Aaron and I think we maybe saw a flash there with the OMC length PZT being driven at full range by a triangle wave.

- with OMC Undulators (aka tip/tilt PZT mirrors) energized, the beam was low on PZT1 mirror. We pitched ITMY by ~150 micro-rad and that centered the beam on PZT1 mirror. ITMY-OL is probably not better than 100 urad as a DC reference?

- We checked the range of Undulator 1 and we were getting ~5 mrad of yaw of the beam for the full range, and perhaps half of that in pitch. Rob Ward emailed us from Oz to say that the range is robably 2.7 mrad, so that checks out.

Even if the ITMY has to be in the wrong position to get the beam to the OMC, we can still do the heater tests in one position and then do the OMC checkout stuff in the other position.

Gautam suspects that there is a possible hysterical behaviour in the Undulators which is related to the MC3 glitching and the slow machine hangups and also possibly the illuminati.

[aaron]

-We noticed a ghost beam that from MC REFL (MMT2) that should be dumped during the next vent--it travels parallel to the OMC's long axis and nearly hits one of the steering mirrors for OMC refl.

-We measured the level of the table and found it ~3 divisions off from level, with the south end tilted up

-Gautam rotated and slightly translated OM5 to realign the optic, as expected. No additional optics were added.

-Gautam and I tested the TT piezo driver. We found that 3.6V on the driver's input gave 75V (of 150V) at the output, at least for yaw on piezo 1. However, as Gautam mentioned, during testing it seemed that the other outputs may have different (nonzero) offset voltages, or some hysterisis.

  4939   Tue Jul 5 16:09:54 2011 kiwamuUpdateABSLsome photos for ABSL setup

Here I show two photos of the latest ABSL (ABSolute Length measurement) setup.

APtable.png

Figure.1 : A picture of the ABSL setup on the AP table.

  The setup has been a little bit modified from the before (#4923).

 As I said on the entry #4923, the way of sampling the ABSL laser wasn't so good because the beam, which didn't go through the faraday, was sampled.

In this latest configuration the laser is sampled after the faraday with a 90% beam splitter.

The transmitted light from the 90% BS (written in pink) is sent to the PSL table through the access tube which connects the AP and PSL table .

 

PSLtable.png

FIgure.2: A picture of the ABSL setup on the PSL table.

 The 10% sampled beam ( pink beam in the picture) eventually comes to the PSL table via the access tube (the hole on the left hand side of the picture).

Then the ABSL beam goes through a mode matching telescope, which consists of a combination of a concave and a convex lens.

The PSL laser (red line in the picture) is sampled from a point after the doubling crystal.

The beam is combined at a 50 % BS, which has been setup for several purposes( see for example #3759 and #4339 ) .

A fast response PD (~1 GHz) is used for the beat-note detection.

  11519   Thu Aug 20 11:09:10 2015 ranaUpdateIOOsome points about seismic FF
  • When plotting the subtraction performance, we mainly care about the 0.5 - 10 Hz band, so we care about the RMS in this band. Don't integrate over the whole band.
  • When calculating the Wiener filter, you must use the pre-weighting so as to not let the Wiener residual be dominated by the out of band signals. We don't want the filter to try to do anything outside of the 0.5 - 10 Hz band.
  • Somehow, we want to assign a penalty for the filter to have high frequency gain. We do NOT want to slap on an ad-hoc low pass filter. The point of the Wiener filtering is to make the optimum.
  • What is the reason for the poor filter performance from 0.5 - 2 Hz ? If we use the frequency domain (Dmass) subtraction technique, we can do better, so there's some inefficiency in this process.
  • we're getting too much of the 3 Hz stack mode coupling into MCL. I think this means that our damping filters should be using RG around the suspension eigenmodes rather than just simple velocity damping. We had this years ago, but it caused some weird interaction with the angular loops...to be puzzled out.
  998   Fri Sep 26 16:08:39 2008 robUpdateLockingsome progress
There's been good progress in locking the last couple of nights. A lot of time was wasted before I found that
all the SUS{POS,PIT,YAW} damping gains on the SRM were set to 0.1 for some reason, which let it get rung up
just a bit during bang locking. After setting these gains to 0.5 (similar to PRM and BS), the initial lock
acquisition of DRMI+2ARMs (nospring) got much quicker. Then more time was wasted by sticky sliders on the
transmon QPD whitening gain, causing the Schmitt triggered HI/LO gain PD switch not to happen. This meant
that the arm power was not reported properly when the CARM offset was reduced, and so loop gain normalizations
were not working properly. After all this, by the end of the night last night, reduced the CARM offset such
that stored power in the arms was about half of the max. Should be able to get to full power with another
good night, and then back to springy locking.
  2030   Thu Oct 1 03:12:56 2009 robUpdateLockingsome progress

Good progress in IFO locking tonight, with the arm powers reaching about half the full resonant maximum. 

Still to do is check out some weirdness with the OMC DAC, fix the wireless network, and look at c1susvme2 timing.

  3458   Mon Aug 23 19:55:31 2010 kiwamuUpdateCDSsome progress

 {Joe, Kiwamu}

Today we did the following works in order to get ready for the new CDS test.

 - solved the DAC issue.

 - checked all the channel assignments of the ADC and the DAC.

 - preparation for modification of the AA filter chassis. 

 - checked DAC cable length.

 - connected the power cables of the BO boards to Sorensens.

 

Although we performed those works, we still couldn't do the actual damping tests.

To do the damping tests, we have to modify the AA chassis to let the SCSIs go in it. Now Joe and Steve are working for this issue.

 Also we found that we should make three more 37pin Dsub - 40pin IDC cables.  

But this is not a critical issue because the cables and the connectors are already in our hands. So we can make them any time later.

 

(Notes)


 (DAC issue)

  Now all the DAC channels are working correctly.  

There had been a combination of some issues.

  When I posted the elog entry last time, the DAC was not working at all (see here).

 But in the last week Joe found that the IO process didn't correctly run. He modified the IOP file named 'c1x02.mdl' and ran it after compiling and installing it.

 This made the situation better because we then were able to see the most of the signals coming out from the DACs.

     However we never saw any signals associated with SIDE_COILs.

 We checked the DAC cards, their slots and their timing signals. But they all were fine.

At that time we were bit confused and spent a couple of days because the DAC signals appeared at a different slot some time after we rebooted the computer. Actually this issue still remains unsolved...

Finally we found that SIDE_COILs had an input matrix which didn't show up in the medm screen.

We put 1 in the matrix and we successfully got the signal coming out from the DAC.

 

(channel assignments)

We checked all the channel assignments of the DACs and the ADCs.

All the channels are assigned correctly (i.e. pin number and channel name).

 

(AA chassis)

 We have been planning to put the SCSI cables into the AA chassis to get the ADC signals.

As Joe said in the past entry (see here) , we need a modification on the AA chassis to let the SCSIs go in it.

Joe and Steve will put an extension component so that we can make the chassis wider and eventually SCSI can go in.

 

 

(DAC cable length)

 In the default plan we are going to reuse some DAC cables which are connected to the existing systems.

To reuse them we had to make sure that the length of those cables are long enough for the new CDS.

After stopping the watchdogs, we disconnected those DAC cables and confirmed they were long enough.

Now those cables are connected to the original place where they have been before.

The same test will be performed for the binary outputs.

 

(power cables to Sorensens)

 Since the binary output boards need +/- 15V power, we hooked up the power cables to Sorensens sitting on the new 1X5 rack.

After cabling them, we turned on the power and successfully saw the green LEDs shining on the back panel of the boards.

  8196   Thu Feb 28 02:43:49 2013 yutaUpdateLSCsome qualitative evidence of PRMI sideband lock

[Manasa, Yuta]

Since we have setup POP22 PD now(elog #8192), we could confirm that sideband power builds up when PRMI is sideband locked.

Plot:
  Here's some plot of PRC intra-cavity powers and MICH,PRCL error signals. As you can see from POP22, we locked at the peak of 11MHz sideband. There was oscillation at ~500 Hz, but we couldn't optimize the gain yet.
PRMIsideband.png


Movie:
  Here's 30 sec movie of AS, POP, REFL when acquiring (and losing) PRMI sideband lock. It was pretty hard to take a movie because it locks pretty seldom (~1 lock / 10 min).



Locking details:
  For MICH lock, we used ITMs instead of BS for reducing coupling between PRCL.
  Also, AS55 phase rotation angle was coarsely optimized by minimizing MICH signal in I.
  For PRCL lock, we used REFL55_I_ERR instead of REFL33_I_ERR. It had better PDH signal and we coarsely optimized phase rotation angle by minimizing PRCL PDH signal in Q.

 == PRMI sideband ==
  MICH: AS55_Q_ERR, AS55_PHASE_R = -12 deg,  MICH_GAIN = -0.1, feedback to ITMX(-1),ITMY(+1)
  PRCL: REFL55_I_ERR, REFL55_PHASE_R = 70 deg, PRCL_GAIN = -15, feedback to PRM

  We set POP22_PHASE_R = -170 deg by minimizing Q.

Issues:
 - We tried to use REFL55_Q_ERR to lock MICH, but couldn't. It looks like REFL error signals are bad.
 - We tried to use POP22_I_ERR to trigger PRCL lock, but it didn't work.

  14907   Thu Sep 26 17:56:28 2019 KojiUpdateCDSsome rebooting

Yesterday (Sep 25) evening: I had to reboot c1psl, c1iool0, and c1aux to recover nominal IMC locking

Today megatron had no response and I had to reboot it with the reset button. MCautolocker and FSSSlow were recovered and the IMC is locking as usual.

  5702   Wed Oct 19 16:53:38 2011 kiwamuUpdateCDSsome screens need labels

Untitled.png

Some of the sub-suspension screens need labels to describe what those row and column are.

ELOG V3.1.3-