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ID Date Author Type Category Subjectup
  7254   Thu Aug 23 10:08:13 2012 SteveUpdatePEMseismometers?

Quote:

It seems as though there is something funny going on around ~1.5 Hz, starting a little over an hour ago.

We see it in the BLRMS channels, the raw seismometer time series, as well as in various suspensions and LSC control signals.  It's also pretty easy to see on the camera views of all the spots (MC, arms, transmissions....AS is a little harder to tell since it's flashing, but it's there too).

The plots I'm attaching are only for ~10min after the jump happened, but there has been no change in the BLRMS since it started.  Usually, we'd see an earthquake in all the channels, and even big ones ring down after a little while.  This is concentrated at a pretty narrow frequency (some of Den's plots for later have this peak), and it's not ringing down, so it's not clear what is going on.

Here is a whole pile of plots.  Recall that the T-240 is plugged into the "STS_3" channels, and we don't have BLRMS for it, so you can look at the time series, but not any frequency specific stuff.

Atm1,  I'm not sure about the seismic data.   Baja earthquake magnitude 3.0 at  yesterday morning.Seismometers do not see them !

Atm2,  No posted seismic activity.  Someone is jump walking in the lab? Why are there time delays between the suspensions?

Attachment 1: bajaMag3.png
bajaMag3.png
Attachment 2: seisvssus.png
seisvssus.png
  13461   Sun Dec 3 05:25:59 2017 gautamConfigurationComputerssendmail installed on nodus

Pizza mail didn't go out last weekend - looking at logfile, it seems like the "sendmail" service was missing. I installed sendmail following the instructions here: https://tecadmin.net/install-sendmail-server-on-centos-rhel-server/

Except that to start the sendmail service, I used systemctl and not init.d. i.e. I ran systemctl start sendmail.service (as root). Test email to myself works. Let's see if it works this weekend. Of course this isn't so critical, more important are the maintenance emails that may need to go out (e.g. disk usage alert on chiara / N2 pressure check, which looks like nodus' responsibilities). 

  13462   Sun Dec 3 17:01:08 2017 KojiConfigurationComputerssendmail installed on nodus

An email has come at 5PM on Dec 3rd.

 

  9578   Mon Jan 27 17:49:46 2014 ranaHowToComputer Scripts / Programssendmail started on nodus: fixing SwiftMail on Dokuwiki

Since the recent filesystem fracas, the new accounts could not be created on nodus / dokuwiki (for the controls workshop, for example).

I started sendmail on nodus using the command:   sudo /etc/init.d/sendmail start

and the SwiftMail plugin on there is now sending out the confirmation emails again. This will happen each time we reboot nodus, so let's replace it.

  13539   Fri Jan 12 12:31:04 2018 gautamConfigurationComputerssendmail troubles on nodus

I'm having trouble getting the sendmail service going on nodus since the Christmas day power failure - for some reason, it seems like the mail server that sendmail uses to send out emails on nodus (mx1.caltech.iphmx.com, IP=68.232.148.132) is on a blacklist! Not sure how exactly to go about remedying this.

Running sudo systemctl status sendmail.service -l also shows a bunch of suspicious lines:

Jan 12 10:15:27 nodus.ligo.caltech.edu sendmail[6958]: STARTTLS=client, relay=cluster6a.us.messagelabs.com., version=TLSv1/SSLv3, verify=FAIL, cipher=DHE-RSA-AES256-GCM-SHA384, bits=256/256
Jan 12 10:15:45 nodus.ligo.caltech.edu sendmail[6958]: w0A7QThE032091: to=<umakant.rapol@iiserpune.ac.in>, ctladdr=<controls@nodus.ligo.caltech.edu> (1001/1001), delay=2+10:49:16, xdelay=00:00:39, mailer=esmtp, pri=5432408, relay=cluster6a.us.messagelabs.com. [216.82.251.230], dsn=4.0.0, stat=Deferred: 421 Service Temporarily Unavailable
Jan 12 11:15:23 nodus.ligo.caltech.edu sendmail[10334]: STARTTLS=client, relay=cluster6a.us.messagelabs.com., version=TLSv1/SSLv3, verify=FAIL, cipher=DHE-RSA-AES256-GCM-SHA384, bits=256/256
Jan 12 11:15:31 nodus.ligo.caltech.edu sendmail[10334]: w0A7QThE032091: to=<umakant.rapol@iiserpune.ac.in>, ctladdr=<controls@nodus.ligo.caltech.edu> (1001/1001), delay=2+11:49:02, xdelay=00:00:27, mailer=esmtp, pri=5522408, relay=cluster6a.us.messagelabs.com. [216.82.251.230], dsn=4.0.0, stat=Deferred: 421 Service Temporarily Unavailable
Jan 12 12:15:25 nodus.ligo.caltech.edu sendmail[13747]: STARTTLS=client, relay=cluster6a.us.messagelabs.com., version=TLSv1/SSLv3, verify=FAIL, cipher=DHE-RSA-AES256-GCM-SHA384, bits=256/256
Jan 12 12:15:42 nodus.ligo.caltech.edu sendmail[13747]: w0A7QThE032091: to=<umakant.rapol@iiserpune.ac.in>, ctladdr=<controls@nodus.ligo.caltech.edu> (1001/1001), delay=2+12:49:13, xdelay=00:00:33, mailer=esmtp, pri=5612408, relay=cluster6a.us.messagelabs.com. [216.82.251.230], dsn=4.0.0, stat=Deferred: 421 Service Temporarily Unavailable

 

Why is nodus attempting to email umakant.rapol@iiserpune.ac.in?

  13540   Fri Jan 12 16:01:27 2018 KojiConfigurationComputerssendmail troubles on nodus

I personally don't like the idea of having sendmail (or something similar like postfix) on a personal server as it requires a lot of maintenance cost (like security update, configuration, etc). If we can use external mail service (like gmail) via gmail API on python, that would easy our worry, I thought.

  13542   Fri Jan 12 18:22:09 2018 gautamConfigurationComputerssendmail troubles on nodus

Okay I will port awade's python mailer stuff for this purpose.

gautam 14Jan2018 1730: Python mailer has been implemented: see here for the files. On shared drive, the files are at /opt/rtcds/caltech/c1/scripts/general/pizza/pythonMailer/

gautam 11Feb2018 1730: The python mailer had never once worked successfully in automatically sending the message. I realized this may be because I had put the script on the root user's crontab, but had setup the authentication keyring with the password for the mailer on the controls user. So I have now setup a controls user crontab, which for now just runs the pizza mailing. let's see if this works next Sunday...

Quote:

I personally don't like the idea of having sendmail (or something similar like postfix) on a personal server as it requires a lot of maintenance cost (like security update, configuration, etc). If we can use external mail service (like gmail) via gmail API on python, that would easy our worry, I thought.

 

  13545   Sat Jan 13 02:36:51 2018 ranaConfigurationComputerssendmail troubles on nodus

I think sendmail is required on nodus since that's how the dokuwiki works. That's why the dokuwiki was trying to send an email to Umakant.

  13546   Sat Jan 13 03:20:55 2018 KojiConfigurationComputerssendmail troubles on nodus

I know it, and I don't like it. DokuWiki seems to allow us to use an external server for notification emails. That would be the way to go.

  4851   Tue Jun 21 23:29:41 2011 kiwamuUpdateLSCsensing matrix measurement

I am now measuring the sensing matrix in the DRMI configuration.

A goal of tonight is to measure the sensing matrix as a test of the script.

 

The result will be updated later.

  4857   Wed Jun 22 17:42:03 2011 kiwamuUpdateLSCsensing matrix measurement

The sensing matrix was measured in the DRMI configuration for the first time.

The measurement was done by an automatic script and the realtime LOCKIN module built in the c1lsc model.

The resultant matrix is still too primitive, so I will do some further analysis.

 

(Measurement of sensing matrix)

 The quantities we want to measure are the transfer functions (TFs) from displacement (or change in optical phase) of each DOF to sensors in unit of [counts/m].

So essentially the measurement I did is the same as the usual TF measurement. The difference is that this measurement only takes TFs at a certain frequency, in this case 283 Hz.

 The measurement goes in the following order :

  (1) Lock DRMI

  (2) Shake an optic of interest longitudinally with an amplitude of 1000 counts at 283.103 Hz, where no prominent noise structures are present in any spectra of the sensor signals.

  (3) Put a notch filter at the same frequency of 283.103 Hz in each DOF (MICH, PRC and SRC) to avoid unwanted suppression due to the control loops.

       (This technique is essentially the same as this one, but this time the control loops are shut off only at a specific frequency )

       The notch filter I put has a depth of 60 dB and Q of 20. The filter eats the phase of ~10 deg at 200 Hz, which still allow servos to run with a high UGF up to 200Hz.

  (4) Take the output signal from a signal port of interest (i.e. REFL11_I, etc.,) and then put it into the realtime LOCKIN module.

  (5) Measure the resultant I and Q signals coming out from the LOCKIN module.

  (6) Repeat the procedure from (2) through (5) for each optic and sensor.

 

(Results)

 Again, the resultant sensing matrix is still primitive, for example the optic-basis should be converted into the DOF basis.

The values listed in the matrix below is the absolute values obtained by operation of sqrt( I^2 + Q^2) plus the polarity according to the output from I and Q of LOCKIN.

Therefore they still contain the actuator response, which is not desired. i will calibrate them into [counts/m] later by using the calibration factor of the actuator responses.

All the raw data showed the relative phase between I and Q either ~ 127 deg or ~ -53 deg.

In my definition, the one has 127 deg is plus polarity and the one has -53 deg is minus polarity.

Technically speaking the polarity depends on the polarity of the actuator and also the direction of the actuator against the DOFs.

Without any excitation the absolute values fluctuated at about 10-4 - 10-5, so the excitation amplitude was big enough to observe the sensing matrix.

Though, I still need to estimate the statistical errors to make sure the SNR is reasonably big.

 

sensemat.png

  Fig.1 Measured sensing matrix from optic to sensors.

 

(Things to be done)

  - convert the optic-basis (i.e. BS, ITMs, PRM and SRM) to the DOF-basis (i.e. MICH, PRC and SRC) so that the matrix is understandable from point of view of the interferometer control.

  - estimate the optimum demodulation phase for each DOF at each sensor port.

  - add some statistical flavors (e.g. error estimations and so on.)

  - edit the script such that it will keep watching the ADC overflows and the coherence to make sure the measurement goes well.

  - add some more signal ports (e.g. REFL55, POY55 and etc.)

  - compare with an Optickle model

Quote from #4851

The result will be updated later.

 

  4899   Tue Jun 28 15:20:08 2011 kiwamuUpdateLSCsensing matrix measurement in PRMI configuration

Here is the result of the measurement of the sensing matrix in the PRMI configuration.

If we believe the resultant matrix, it is somewhat different from what we expected from a finesse simulation (summary of simulated sensing matrix).

 


(Motivation)

As a part of the DRMI test plan, we wanted to check the sensing matrices and consequently diagonalize the LSC input matrix.

The matrix of the DRMI configuration has been measured (#4857), but it was a bit too complicated as a start point.

So first in order to make sure we are doing a right measurement, we moved onto a simpler configuration, that is PRMI.

 

(measurement)

The technique I used was the same as before (#4857) except for the fact that SRM wasn't included this time.

   - PRC was locked to the carrier resonant point. The UGF of MICH and PRC were ~ 110 Hz and 200 Hz respectively.

   - Longitudinally shook BS, ITMs and PRM at 283.103 Hz with an amplitude of 1000 counts using the LOCKIN oscillator in C1LSC.

   - Took the I and Q phase signals from the LOCKIN outputs.

The table below is the raw data obtained from this measurement :

rawmatrix.png

 

(Conversion of matrix)

 With the matrix shown above, we should be able to obtain the sensing matrix which gives the relation between displacements in each DOF to each signal port.

The measured matrix connects two vectors, that is,

       (signal port vector) = [Measured raw matrix] (SUS actuation vector),   -- eq.(1)

where

       (signal port vector) = (AS55_I, AS55_Q, REFL11_I, REFL11_Q)T   in unit of [counts],

    (SUS actuation vector) = (BS, ITMX, ITMY, PRM)T   in units of [counts].

Now we break the SUS actuation vector into two components,

       (SUS actuation vector [counts])  = (actuator response matrix [m/counts])-1 * (MICH, PRM [m] )^T   -- eq.(2)

 where

       (actuator response matrix) =  2.05x10-13 * ( [1   ,  0.217, -0.216,   0  ],

                                                 [ 0.5,  0.109 -0.108, 0.862]  )  in unit of [m/counts]

These values are coming from the actuator calibration measurement.

In the bracket all the values are normalized such that BS has a response of 1 for MICH actuation.

Combining eq.(1) and (2) gives,

     (signal port vector) = (measured raw matrix) * (actuator response matrix)-1 * (MICH, PRM)T

And now we define the sensing matrix by

     (sensing matrix) = (measured raw matrix) * (actuator response matrix)-1

The sensing matrix must be 4x2 matrix.

For convenience I then converted the I and Q signals of each port into the absolute value and phase.

       ABS = sqrt((AAA_I)2 +(AAA_Q)2 ),

       PHASE = atan (AAA_Q / AAA_I),

where AAA is either AS55 or REFL11.

 

(Resultant matrix)

The table below is the resultant sensing matrix.

ABS represents the strength of the signals in unit of [cnts/m], and PHASE represents the demodulation phases in [deg].

sensmat.png

There are several things which I noticed :

   - The demodulation phase of MICH=>AS55 and PRC=>REFL11 are close to 0 or 180 deg as we expected.

      This is a good sign that the measurement is not something crazy.

   - AS55 contains a big contribution from PRC with a separation angle of 152 deg in the demodulation phase.

     In AS55 the signal levels of MICH and PRC were the same order of magnitude but PRC is bigger by a factor of ~4.

     However the finesse simulation (see wiki page) shows a different separation angle of 57 deg and MICH is bigger by factor of ~6.

  - REFL11 is dominated by PRC. The PRC signal is bigger than MICH by a factor of ~100, which agrees with the finesse simulation.

    However the separation angle between PRC and MICH are different. The measurement said only 19 deg, but the simulation said ~ 90 deg.

  - Woops, I forgot to calibrate the outputs from the LOCKIN module.

    The whole values must be off by a certain factor due to the lack of the calibration , but fortunately it doesn't change the demodulation phases.

Quote from #4884

I was able to measure the sensing matrix in the PRMI configuration.

The results will be posted later.

 

  4910   Wed Jun 29 12:20:53 2011 kiwamuUpdateLSCsensing matrix measurement in PRMI configuration

Of course I made a mistake in my calculation of the sensing matrix. I will figure out which point I mistook.

The MICH signal must have the demodulation phase of around 90 deg in AS55

because we had adjusted the demodulation phase such that the MICH signal mostly appears on AS55_Q.

Quote:

Here is the result of the measurement of the sensing matrix in the PRMI configuration.

sensmat.png

  6281   Wed Feb 15 05:29:22 2012 kiwamuUpdateLSCsensing matrix of PRMI

I have measured the sensing matrix of PRMI.

It seems that the MICH signal in the 3f ports (REFL33 and REFL165) were quite tiny, and because of that it is very tough to use them for the actual MICH control.

The data is coming soon.

  6283   Wed Feb 15 17:15:33 2012 kiwamuUpdateLSCsensing matrix of PRMI

I think I have told a lie in the last meeting -- the measured sensing matrix doesn't look similar to what Optickle predicts.

Smells like something is very wrong.

 

Measured sensing matrix

The measured matrix are shown in the diagram below.
The lengths of arrows corresponds to the signal strength in unit of V/m. The radial axis in in log scale.
The angle of arrows corresponds to their best demodulation phases.
sensingMAT.png

        Some obvious things:

  •  REFL11 : The separation angle between MICH and PRCL is narrow and it is far from the ideal 90 degree. This doesn't agree with the simulation.
  •  REFL33:  The MICH and PRCL signals are almost degenerated in their demodulation phase.
  •  REFL55 :  It shows non-90 degree separation. This doesn't agree with the simulation.
  •  REFL165 : The separation is close to 90 degree, but the signals are small. And I am not sure if the MICH signal is real or just noise.
  •  AS55 : Somehow it shows a nice 90 degree separation, but this result doesn't agree with the simulation.

 


Expected sensing matrix from a simulation

For a comparison here is a result from an Optickle simulation.
This time the radial unit is W/m instead of V/m, but they are qualitatively the same unit.
The radial axis is in log, so when it says 2, it means 10^2 [W/m].
PRMI_Optickle.png
 
 Simulation setup:
l_PRC  = 6.760 (see #4064)
l_asy  = 0.0364  (see #4821)
loss per optic = 50 ppm
 

Measurement

  •  Locked PRMI with the carrier anti-resonating in PRCL.
  •  Adjusted the control gains for both the MICH and PRCL control to have UGFs at ~ 100 Hz.
  •  Put a 30 dB notch filter  in each control servo at 283.1 Hz where an excitation signal will be.
  •  Excited PRCL and MICH at different time via the realtime lockng in the LSC front end. The amplitude is 1000 counts and the frequency is at 238.1 Hz.
    • For the MICH excitation, I have coherently and differentially excited ITMs
  •  Used DTT to take a transfer function (transfer coefficients at 283.1 Hz) from the lockin oscillator to each LSC demodulated signal.
    • Including AS55I/Q, REFL11I/Q, REFL33I/Q, REFL55I/Q and REFL165I/Q.
  •  Calibrated the obtained transfer functions from unit of counts/counts to V/m using the actuator response (#5637)

Quote from #6281
I have measured the sensing matrix of PRMI.
It seems that the MICH signal in the 3f ports (REFL33 and REFL165) were quite tiny, and because of that it is very tough to use them for the actual MICH control.
The data is coming soon.

  6287   Thu Feb 16 07:38:24 2012 KojiUpdateLSCsensing matrix of PRMI

So why don't you use AS55I and Q for the control of PRMI???

  6289   Thu Feb 16 13:12:30 2012 ranaUpdateLSCsensing matrix of PRMI

Quote:

I think I have told a lie in the last meeting -- the measured sensing matrix doesn't look similar to what Optickle predicts.

Smells like something is very wrong.

 Those Radar plots are awesome. Even more awesome would be if they were in units of W/m (so that it can be directly compared with Optickle) and so that the numbers are useful even 1 year from now. Otherwise, we will lose the RF transimpedance information and thereby lose everything.

Also, please post the provenance of the counts->V calibration.

  6293   Fri Feb 17 04:45:48 2012 kiwamuUpdateLSCsensing matrix of PRMI

I locked the PRMI with the AS55I and Q combination.

It seems the glitche rate decreased,

but I am not 100 % sure because the rest of the demod signals (i.e. REFL11 and etc) were showing relatively big signals (noise ?), which may cover the glitches.

Also the optical gain of PRCL at AS55I doesn't agree with my expectation based on the obtained sensing matrix (#6283).

It looks too low and lower than the measured sensing matrix by a factor of 50 or so.

I will continue working on this configuration tomorrow and then move on to the SRMI locking as a part of the glitch hunting activity.

Quote from #6287

So why don't you use AS55I and Q for the control of PRMI???

  4427   Wed Mar 23 05:11:08 2011 kiwamuUpdateGreen Lockingservo handig off

Succeeded in handing off the servo from the green to the red.

stripTransit_edit.png

 

 


(noise performance)

 This time we found that the fluctuation in the IR signals became lesser as the gain of the ALS servo increased.

Therefore I increased the UGF from 40 Hz to 180 Hz to have less noise in the IR PDH signal.

Here is a preliminary plot for today's noise spectra.

noise_curve20110322_hUGF.png

The blue curve is the ALS in-loop spectrum, that corresponds to the beat fluctuation.

The red curve is an out-of-loop spectrum taken by measuring the IR PDH signal.

Since the UGF is at about 180 Hz the rms is integrated from 200 Hz.

The residual displacement noise in the IR PDH signal is now 1.2 kHz in rms.

I am going to analyze this residual noise by comparing with the differential noise that I took yesterday (see the last entry ).

  4428   Wed Mar 23 08:50:36 2011 AidanUpdateGreen Lockingservo handig off

Nicely done!

 

Quote:

Succeeded in handing off the servo from the green to the red.

stripTransit_edit.png

 

 

 

Attachment 1: green-to-red.jpg
green-to-red.jpg
  9151   Sun Sep 22 21:28:53 2013 ranaUpdateSUSset OL T RAMP values (they are not visible on the OL screens)

controls@rosalba:/opt/rtcds/caltech/c1/scripts/SUS 0$ ./setOLtramps
Old : C1:SUS-ETMX_OLPIT_TRAMP        0
New : C1:SUS-ETMX_OLPIT_TRAMP        2
Old : C1:SUS-ETMX_OLYAW_TRAMP        0
New : C1:SUS-ETMX_OLYAW_TRAMP        2
Old : C1:SUS-ETMY_OLPIT_TRAMP        2
New : C1:SUS-ETMY_OLPIT_TRAMP        2
Old : C1:SUS-ETMY_OLYAW_TRAMP        2
New : C1:SUS-ETMY_OLYAW_TRAMP        2
Old : C1:SUS-ITMX_OLPIT_TRAMP        0
New : C1:SUS-ITMX_OLPIT_TRAMP        2
Old : C1:SUS-ITMX_OLYAW_TRAMP        0
New : C1:SUS-ITMX_OLYAW_TRAMP        2
Old : C1:SUS-ITMY_OLPIT_TRAMP        0
New : C1:SUS-ITMY_OLPIT_TRAMP        2
Old : C1:SUS-ITMY_OLYAW_TRAMP        0
New : C1:SUS-ITMY_OLYAW_TRAMP        2
Old : C1:SUS-BS_OLPIT_TRAMP          0
New : C1:SUS-BS_OLPIT_TRAMP          2
Old : C1:SUS-BS_OLYAW_TRAMP          0
New : C1:SUS-BS_OLYAW_TRAMP          2
Old : C1:SUS-PRM_OLPIT_TRAMP         0
New : C1:SUS-PRM_OLPIT_TRAMP         2
Old : C1:SUS-PRM_OLYAW_TRAMP         0
New : C1:SUS-PRM_OLYAW_TRAMP         2
Old : C1:SUS-SRM_OLPIT_TRAMP         0
New : C1:SUS-SRM_OLPIT_TRAMP         2
Old : C1:SUS-SRM_OLYAW_TRAMP         0
New : C1:SUS-SRM_OLYAW_TRAMP         2
 
Done setting TRAMPs

  8809   Tue Jul 9 11:37:37 2013 gautamUpdateCDSset up for testing DAC Interface-board pin outs

The bank marked channel 9-16 is free, but the connector is a 40 pin IDC and I need to know the exact pin-out configuration before I can set about making the custom ribbon cable that will send the control signals from the DAC card to the PZT driver board. 

The DAC interface board on rack 1Y4 seems to be one of the first versions of this board, and has no DCC number anywhere on it. Identical modules on other racks have the DCC number D080303, but this document does not exist and there does not seem to be any additional documentation anywhere. The best thing I could find was the circuit diagram for the ADL General Standards 16-bit DAC Adapter Board, which has what looks like the pin-out for the 68 pin SCSI connector on the DAC Interface board. Koji gave me an unused board with the same part number (D080303) and I used a multimeter and continuity checking to make a map between DAC channels, and the 40 pin IDC connector on the board, but this needs to be verified (I don't even know if what is sitting inside the box on 1Y4 is the same D080303 board).

Jenne suggested making a break-out cable to verify the pin-outs, which I did with a 40-pin IDC connector and a bit of ribbon wire. The other end of the ribbon wire has been stripped so that we can use some clip-on probes and an oscilloscope to verify the pin-outs by sending a signal to DAC channels 9 through 16 one at a time. On the software side, Jenne did the following:

  • Restarted the mx_stream on c1iscey  (unrelated to this work)
  • 8 Excitation points added in the simulink model on c1scy 
  • Model compiled and installed

We have not restarted c1scy yet as Annalisa is working on some Y-arm stuff right now. We will restart c1scy and use awggui to perform the test once she is done.

 Pink edits by JCD

  8811   Tue Jul 9 12:01:20 2013 gautamUpdateCDSset up for testing DAC Interface-board pin outs

 

 Jenne just rebooted c1scy and daqd on the framebuilder. We will do the actual test after lunch.

  3407   Thu Aug 12 11:59:31 2010 kiwamuHowToCDSset up ntp daemom

(sad story)

When I was working on a new front end machine c1sus, I found that make command didn't run and gave the following message.

      "make:warning:clock skew detected.Your build may be incomplete"

This was caused by a clock difference between the nfs (nodus) and the terminal machine (c1sus).

I had to set up ntp daemon to synchronize them. Here is a procedure to set up it

 


(how to)

- log in to a front end machine

              ssh c1sus

- enable the ntp daemon

              sudo ntsysv

- configure the ntpd

              vi (emacs)  /etc/ntp.conf

- below is the contents I wrote on ntp.conf

             server 192.168.113.200  minpoll 4 maxpoll 4 iburst

      driftfile /var/lib/ntp/drift

 - let the daemon run
            sudo service ntpd start
- check it if it's running
             ntpq -p
  1529   Tue Apr 28 16:36:24 2009 robHowToLockingsetting the RF CARM demod phase

To set the demod phase for RF CARM, sensed at REFL2 (REFL 166I), it suffices to set the demod phase for REFL2 to be the optimal phase for controlling SRCL in a no-arm state.

Attachment 1: CARM_phases_REFL.pdf
CARM_phases_REFL.pdf CARM_phases_REFL.pdf CARM_phases_REFL.pdf CARM_phases_REFL.pdf
Attachment 2: SRCL_phases_REFL.pdf
SRCL_phases_REFL.pdf SRCL_phases_REFL.pdf SRCL_phases_REFL.pdf SRCL_phases_REFL.pdf
  1530   Tue Apr 28 17:51:13 2009 robHowToLockingsetting the RF CARM demod phase

Quote:

To set the demod phase for RF CARM, sensed at REFL2 (REFL 166I), it suffices to set the demod phase for REFL2 to be the optimal phase for controlling SRCL in a no-arm state.

 

For POX33, the ideal phase for single arm locking does not yield a zero-offset CARM signal.  So the offset needs to be manipulated digitally. 

Attachment 1: XARM_phases_POX.pdf
XARM_phases_POX.pdf XARM_phases_POX.pdf XARM_phases_POX.pdf XARM_phases_POX.pdf
Attachment 2: CARM_phases_POX.pdf
CARM_phases_POX.pdf CARM_phases_POX.pdf CARM_phases_POX.pdf CARM_phases_POX.pdf
  3630   Thu Sep 30 18:51:50 2010 yutaUpdateComputerssetting up aldabella and mariabella

(Kiwamu, Yuta)

Background:
 We wanted to make aldabella and mariabella know how to work.

What we did:

1. Added 2 lines to /etc/rc.local
 /sbin/modprobe ndiswrapper
 sleep 10
 mount linux1:/home/cds/ /cvs/cds


2. Edited ~/.cshrc
 source /cvs/cds/caltech/cshrc.40m

Result:
 Working environment is set to aldabella and mariabella. They have their access to the main system, linux1, now.

Note:
 fstab doesn't work for aldabella and mariabella because the mount should be done after ndiswrapper loads.

  13409   Mon Nov 6 09:09:43 2017 SteveUpdateVACsetting up new TP2 turbo

Our new Agilent Technology TwisTorr 84FS AG rack controller ( English Manual pages 195-297 )  RS232/485, product number X3508-64001, sn IT1737C383

This controller, turbo and it's drypump needs to be set up into our existing vacuum system. The intake valve of this turbo (V4) has to have a hardwired interlock that closes V4 when rotation speed is less than 20% of preset RPM speed.

The unit has an analoge 10Vdc output that is proportional to rotation speed. This can be used with a comperator to direct the interlock or there may be set software option in the controller to close the valve if the turbo slows down more than 20%

The last Upgrade of the 40m Vacuum System  1/2/2000 discribes our  vauum system  LIGO-T000054-00-R 

Here the LabView / Metrabus controls were replaced by VME processor and  an Epic interface

We do not have schematics of the hardware wiring.

We need help with this.

 

  3892   Thu Nov 11 05:56:04 2010 yutaSummaryIOOsetting up temporary oplev for coil balancing of MCs

(Suresh, Yuta)

Background:
  Previous A2L measurement is based on the assumption that actuator efficiencies are identical for all 4 coils.
  We thought that the unbelievable "tilt" may be caused by imbalance of the coils.

Method:
  1. Setup an optical lever.
  2. Dither the optic by one coil and demodulate oplev outputs(OL_PIT or OL_YAW) in that frequency.
  3. Compare the demodulated amplitude. Ideally, the amplitude is proportional to the coil actuation efficiency.

What we did:
[MC2]
  MC2 is the least important, but the easiest.
  1. Placed a red laser pointer at MC2 trans table. During the installation, I moved the mirror just before QPD.
  2. Made a python script that measures coil actuation efficiency using the above method. I set the driving frequency to 20Hz.
  It is /cvs/cds/caltech/users/yuta/scripts/actuatorefficiency.py.
  The measurement result is as follows. Errors are estimated from the repeated measurement. (Attachment #1)

MC2_ULCOIL 1
MC2_URCOIL 0.953 ± 0.005
MC2_LRCOIL 1.011 ± 0.001
MC2_LLCOIL 0.939 ± 0.006


[MC1]
  For MC1, we can use the main laser and WFS1 QPD as an oplev.
  But we only have slow channels for QPD DC outputs(C1:IOO_WFS1_SEG#_DC).
  So, we intentionally induce RF AM by EOM(see Kiwamu's elog #3888) and use demodulated RF outputs of the WFS1 QPD(C1:IOO_WFS1_I/Q#) to see the displacement.
  1. Replaced HR mirror in the MCREFL path at AP table to BS so that we can use WFS1.(see Koji's elog #3878)
    The one we had before was labeled 10% pick-off, but it was actually an 1% pick-off.
  2. Checked LO going into WFS1 demodulator board(D980233 at 1X2).
    power: 6.4dBm, freq: 29.485MHz
  3. Turned on the hi-voltage(+100V) power supply going into the demodulator boards.
  4. Noticed that no signal is coming into c1ioo fast channels.
    It was because they were not connected to fast ADC board. We have to make a cable and put it in.

[MC3]
  Is there any place to place an oplev?

Plan:
 - prepare c1ioo channels and connections
 - I think we'd better start A2L again than do oplev and coil balancing.

Attachment 1: MC2coils.png
MC2coils.png
  3771   Sun Oct 24 18:06:35 2010 kiwamuSummaryLockingsetup for green beat

green_beat_note.png

(notes on signal level)

 The signal level of the observed peak was -48dBm.

However I was expecting it is like -28dBm with some ideal assumptions.

There may be a 20dB unknown loss which sounds big to me.

 

The expectation was calculated by using the following simple math.

                       SIGNAL = A x Z x G_RF x sqrt(P1 / 2) x sqrt (P2 / 2)

 where A is the responsibility of the PD and Z is the trans impedance gain. G_RF is a gain of the RF amplifier.

The laser powers of green beams, P1 and P2, are divided by 2 due to a beam splitter. 

I was assuming the parameters are like:

           A = 0.39 [A/W]   (assuming 90% quantum efficiency at 532nm)

           Z = 240 [V/A]  

           P1 = 17 uW  (measured by Newport power meter)

           P2 = 30 uW (measured by Newport power meter)

           G_RF = 23 dB

 

  3774   Mon Oct 25 02:14:38 2010 KojiSummaryLockingsetup for green beat

- What is the actual photocurrent for the beam1 and beam2? We don't care how much power do you have before the BS, but care how much current do you have on the PD.

- How much is the visibility? There is mismatching of the beams. i.e. The beam diameter looked quite different. Also the beams are not TEM00 but have fringes probably comes from the TT mirrors. You maybe able to measure the visibility by the DC output, making the beat freq go through df=0 slowly.

- What is the measured gain of the RF amp? Does it include the voltage division by the output/input impedance?

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

 The signal level of the observed peak was -48dBm.

However I was expecting it is like -28dBm with some ideal assumptions.

There may be a 20dB unknown loss which sounds big to me.

I was assuming the parameters are like:

           A = 0.39 [A/W]   (assuming 90% quantum efficiency at 532nm)

           Z = 240 [V/A]  

           P1 = 17 uW  (measured by Newport power meter)

           P2 = 30 uW (measured by Newport power meter)

           G_RF = 23 dB

  647   Tue Jul 8 10:26:30 2008 MashaUpdateAuxiliary lockingsetup updates
Yesterday I changed one of the beam splitters in the Mach Zehnder to one with a more stable mount as to reduce the system's coupling to environmental noise.

With help from John, I worked out how to get the signals from the two channels of the interferometer into the digital system. I put up BNC cables along part of the Y arm to connect the output of the detectors into the digital channels.
  3645   Mon Oct 4 19:48:00 2010 yutaUpdateVACseveral mirrors installed to ITMX/BS chamber

(Koji, Kiwamu, Yuta)

Lots of progress for the optics placement in the vacuum chamber.
We are ready to go to the next step: open the access connector between IMC and OMC.
 


Background:

The actual work in the vacuum chamber started.
The first goal of the vent is to get the green beam coming out from the chambers to the PSL table.


What we did:

1. Inspection of the tip-tilt suspension

The alignments of the TTs were inspected. We had five TTs having been sitting on the table in Bob's clean room.
Prior to their installation we checked the alignments of those because they sometimes showed large hysteresis mainly in the pitch directions.

If a TT has the hysteresis, the pitch position doesn't come back to the previous position. This may cause an issue of the interferometer operation.

- SN001, SN003, SN005 looked well aligned and show no hysteresis.

- The alignment of SN002 was not so good (theta ~ 0.004 rad ) compared to those three, but no hysteresis, we think this guy is still acceptable for the installation.

- SN004 had an apparent hysteresis. This guy doesn't come back to the previous place, being applied a touch. We have to fix this at some point.

2. Work in the ITMX chamber

Now all of the optic in this chamber was installed in the approximate place.

- Installed POX/POP steering mirrors.

- TT(SN003) was placed.

- The two steering optics for ITMX OPLEV were placed at the designed positions.

3. Work in the BS chamber

Installed 2 TTs to the BS chamber.
- SR3: TT(SN001)
- PR3: TT(SN005)

After the alignment of the green steering mirrors, we confirmed
the green beam is successfully hitting the west wall of the OMC chamber.

Those TTs are approximately aligned using the weakly reflected green beams.

Next work:

- Open the access connector

- Place another periscope and two steering mirrors for green

- Damping of the suspended optics

- Resurrect MC and its stable lock

- Remove MCT pickoff path

- Align optics in the main path

- Recycled Michelson lock

 

Attachment 1: P1060901.JPG
P1060901.JPG
Attachment 2: P1060904.JPG
P1060904.JPG
  15162   Tue Jan 28 08:26:53 2020 ranaFrogsPEMshaking

https://breakthrough.caltech.edu/magazine/2019-aug/#article-Listening-with-Light

  84   Thu Nov 8 15:57:53 2007 tobinConfigurationPSLshelf removed
I removed the sheet metal shelf from the PSL enclosure, for easier access to the ISS.

ISS investigations ongoing.
  13532   Thu Jan 11 14:47:11 2018 SteveUpdatePSLshelf work for tomorrow

I have just received the scheduling of the PSL self work for tomorrow. Gautam and I agreed that if it is needed I will shut the laser off and cover the hole table with plastic.

  7083   Fri Aug 3 13:05:28 2012 DenUpdatePEMshims

As we do not have legs for Trillium, I was advised to use shims to adjust the levels. However, they produce extra resonance at ~30 Hz + harmonics. Coherence is lost at these frequencies.

shims.png

  7084   Fri Aug 3 14:52:11 2012 JenneUpdatePEMshims

Quote:

As we do not have legs for Trillium, I was advised to use shims to adjust the levels. However, they produce extra resonance at ~30 Hz + harmonics. Coherence is lost at these frequencies.

 Brian Lantz / Dan Clark are looking around their lab to see if they forgot to ship the feet with the T-240.  They had taken the feet off to put it in a pod. 

  3434   Wed Aug 18 12:24:58 2010 josephb,kiwamuUpdateCDSshmem issue

Apparently its possible to have working models get into a bad state in regards to shared memory, which prevents the model from working after killing it and restarting it.  We found that by shutting all the models down, and then killing and restarting the setup_shmem process, it allowed models to function properly again.

The symptom was getting stuck at the burt restore step, according the log files (/opt/rtcds/caltech/c1/target/c1SYS/logs/log.txt).

  7780   Tue Dec 4 10:44:36 2012 SteveUpdatePEMshort power outage

 

CALIFORNIA INSTITUTE OF TECHNOLOGY

                 FACILITIES MANAGEMENT

 

**PLEASE POST**

 

 

Building:         Campus

 

Date:             Thursday October 04,2012

 

This morning at 2:17 a.m. much of the City of Pasadena including our Campus experienced a electric power sag of short duration, approximately 1/10 of a second. The cause was a fault on one of Pasadena’s 17KV circuits. Some sensitive equipment have been impacted.

                 

Contact:          Mike Anchondo x-4999

  14914   Mon Sep 30 13:20:55 2019 aaronUpdateIOOshot noise measurement

I wanted to measure the RF transimpedance of the WFS heads, as outlined above.

Summary: Measurement is not done.

Details:

  • closed the PSL shutter
  • taped over the WFS 2 opening with frosted scotch tape
  • illuminated the QPD with an incandescent flashlight.
    • All of the D batteries were close to dead, so it seemed dimmer than usual
  • Observed the WFS2 segment 1 RF spectrum on the Agilent, but saw no difference between the spectrum with and without the flashlight. Must need a brighter light, and possibly also better alignment.
  • Needed to skype someone and pass off the IFO to gautam, so I untaped the QPD, returned the appropriate LEMO connector, and opened the PSL shutter.
  5328   Wed Aug 31 11:37:56 2011 steveUpdateGreen Lockingshutter in place at east end

Uniblitz mechanical shutter installed in the green beam path at ETMY-ISCT  The remote control cable has not been connected.

  9319   Wed Oct 30 14:58:44 2013 SteveHowToGeneralshutting down a computer

 

 We have tried to ssh into c1iscey yesterday morning. It just did not work. We have just tried it again (now) and it did work.

Lesson learned: always shut down the computer from a TERMINAL Do not turn it off by the manual power switch.

  5598   Mon Oct 3 04:43:03 2011 kiwamuUpdateLSCsideband-resonance PRMI locked

My goal of today was to lock PRMI without using AS55 and it is 50% successful.

The sideband-resonance PRMI (SB-PRMI) was locked with REFL33_I and REFL55_Q for the PRCL and MICH control respectively.

The carrier-resonance PRMI wasn't able to be locked without AS55.

     (it looked no clean MICH signals at the REFL ports.)

 


(Motivation)

 The motivation of not to use AS55 came from the suspicion that AS55 was injecting some noise into MICH (#5595).

So I wanted to try another RFPD to see if it helps the stability or not. 

 

(locking activity)

  The lock of SB-PRMI was quite stable so that it stayed locked more than 30 minutes (it ended because I turned off the servos.)

Then I briefly tried DRMI while PRCL and MICH kept locked by the same control loops, namely REFL33_I and REFL55_Q.

The lock of MICH and PRCL looked reasonably robust against the SRCL fringes, but wasn't able to find a good signal for SRCL.

I think I am going to try locking DRMI tomorrow.

 - - settings

    Demod phase for REFL55 = -45.3 deg

    Demod phase for REFL33 = -14.5 deg

    Whitening gain for REFL55 = 4 (12 dB)

    Whitening gain for REFL33 = 10 (30 dB)

    MICH gain = 100

    PRCL gain = 8

 

(misc.)

 + I removed an iris on the ITMY table because it was in the way of POY. See the picture below.

ITMYtable.png

 

  + I found that burtrestore for the ETMX DC coil forces were not functional.

  => currently ETMX's "restore" and "mislalign" buttons on the C1IFO_ALIGN screen are not working.

  => According to the error messages, something seemed wrong on c1auxex, which is a slow machine controlling the DC force.

  4361   Sat Feb 26 02:33:16 2011 kiwamuUpdateGreen Lockingsidebands on beatnote

The power ratio of the beatnote signal vs. the 216kHz sideband has been measured.

The measured ratio was -55 dB, which is smaller by about 20 dB than Aidan's estimation.

To confirm this fact we should check the modulation depth of the end PDH somehow.

 

The below is a picture showing the sidebands around the beatnote locked at 66.45 MHz.

Other than the +/-216 kHz sidebands, we can see some funny peaks at +/- 50 kHz and +/-150 kHz

I wonder if they come from the servo oscillation of the MC servo whose UGF is at 24 kHz.  We can check it by unlocking the MC.

beat_note.png

Quote: #4351 by Aidan

So, on the vertex PD, the power of the 80MHz +/-200kHz sidebands should be around sqrt(0.15)*0.05 = 0.02 = 2% of the 80MHz beatnote.

Once we get the green and IR locked to the arm again, we're going to look for the sidebands around the beatnote.

  4362   Sun Feb 27 09:43:59 2011 AidanUpdateGreen Lockingsidebands on beatnote

Can we set up a fiber-PD on the end table to look at the beat between the "end laser IR beam" and the "PSL IR beam fiber-transmitted end beam"? 

We should see the same thing on that PD that we see on the green PD (plus any fiber noise and I'm not really sure how much that'll be off the top of my head). If we unlock the lasers from the arm cavity then the free-running noise of the lasers wrt to each other will probably swamp the 50kHz and 150kHz signals. Maybe we could lock the end laser to the free-running PSL by demodulating the beat note signal from the fiber-PD and then we could look for the extra sidebands in the IN-LOOP signal. Then we could progressively lock the PSL to the MC and arm cavity and see if the sidebands appear on the fiber-PD at some point in that process. 

It's possible that the 216kHz drive of the PZT on the Innolight is somehow driving up some sub-harmonics in the crystal. I think this is unlikely though: if you look at Mott's measurements of the Innolight PZT response, there are no significant PM resonances at 50 or 150kHz.

 

Quote:

Other than the +/-216 kHz sidebands, we can see some funny peaks at +/- 50 kHz and +/-150 kHz.

 

Quote: #4351 by Aidan

So, on the vertex PD, the power of the 80MHz +/-200kHz sidebands should be around sqrt(0.15)*0.05 = 0.02 = 2% of the 80MHz beatnote.

Once we get the green and IR locked to the arm again, we're going to look for the sidebands around the beatnote.

 

  4363   Sun Feb 27 13:09:56 2011 ranaUpdateGreen Lockingsidebands on beatnote

When Koji and I were massaging the MC, we noticed that the oscillations were at 48.5 kHz. They were pretty huge and are probably what you're seeing on the beat. My guess is that they are the PZT resonances of the PSL 2W NPRO; we need to put a notch in the FSS box - it still has the notch from the old NPRO.

  2757   Thu Apr 1 20:29:02 2010 HartmutUpdateGreen Lockingsimple PD test circuit

I made a simple PD test circuit which may allow to test PD response up to few 100MHz.

Its not for low noise, only for characterising PD response.

Here is the circuit:

The 2 capacitor values (for bypassing) are kind of arbitrary, just what I found around

(one medium, one small capacity). Could be improved by better RF types (e.g. Mica).

The PD type has no meaning. I put in the Centronic 15-T5 for a start.

The bias can be up to 20V for this diode.

The signal appears across R1. It is small, to make a large bandwidth.

R2 is just for slightly decoupling the signal from the following RF amplifier.

The wire into the RF amplifier is short (~cm). And the amplifier is supposed to have 50 Ohm

input impedance.

I use a mini circuits ZFL 500 here.

power supply for this is 15V.

pdtest.png

  3048   Thu Jun 3 22:33:31 2010 valeraSummaryCDSsimulated plant work

 I put matlab files and a summary into the 40m wiki for the fitting of the 40m Optickle transfer functions and generating digital filters for the simulated plant:

http://lhocds.ligo-wa.caltech.edu:8000/40m/Generating_DOF-%3EPD_digital_filters_based_on_Optickle_modeling

The filters are not loaded yet. Joe and Alex will make a rcg code to make a matrix of filters (currently 5x15=75 elements) which will enable the simulated plant tf's.

Joe and I tried to put a signal through the DARM loop but the signal was not going through the memory location in the scx part of the simulated plant.

 

Edit by Joe:

I was able to track it down to the spx model not running properly.  It needed the Burt Restore flag set to 1.  I hadn't done that since the last rebuild, so it wasn't actually calculating anything until I flipped that flag.  The data is now circulating all the way around.  If I turn on the final input (the same one with the initial 1.0 offset), the data circulates completely around and starts integrating up.  So the loop has been closed, just without all the correct filters in.

  6874   Tue Jun 26 01:30:13 2012 yutaSummaryGreen Lockingsimultaneous hold and release of the arm (aka two arm ALS)

To get the feeling of the master of IFO, I;

1. Stabilized both arm length using ALS.

2. Ran findIRresonance.py for both arms and find what offset gives me IR resonances.

3. Holded X arm to IR resonance, holded Y arm to IR resonance, and released both arms.

Below is the time series data of what I did.
ALSboth20120625_2withAS.png


Issues:
 - Currently ALS is not stable enough. It only stays for about few minutes. I think it is because of the bad alignment of green from each end.
 - We can't tell end green frequency is higher or PSL green frequency is higher. So, the sign of the servo filter sometimes flips.
 - Wobbliness of X end green transmission beam spot was from the ETMX oplev. When the oplev servo is on, it got more wobbly when X end table is opened. But when the oplev servo was off, wobbliness was same even if the presence of air flow.
 - MICH contrast in plot above seems like it somehow got better when two arms are at resonance by ALS. I think this is not real because reflection from both arms at AS port was not well aligned and beam was clipped. Koji and I measured contrast of FPMI and MI(ETMs misalined), and they were 99.6 % and 99.9 % respectively. Beam clipping seems like it comes from some where between BS to AS port. We need to figure out where and fix this.

Things need to be done to make ALS more concrete:
 - Align Y end green beam!
 - Look into Y end green frequency servo
 - How do we hand-off servo using ALS to IR lock?
 - Noise budgeting for new phase tracker scheme
 - Linearity check of the beat box and phase tracker

ELOG V3.1.3-