40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log, Page 302 of 341  Not logged in ELOG logo
ID Date Author Typedown Category Subject
  37   Wed Oct 31 09:45:28 2007 waldmanOtherOMCResolution to DAQland saga
[Jay, Sam]

We did a rough accounting for the linear delay this morning and it comes out more or less correct. The 10 kHz 3rd order butterworth AA/AI filter gives ~90 degrees of phase at 6 kHz, or 42 microseconds. Taken together, the two AA and AI filters are worth 80 microseconds. The 1.5 sample digital delay is worth 1.5/32768 = 45 microseconds. The remaining 160 - 125 = 35 microseconds is most likely taken up by the 64 kHz to 32 kHz decimation routine, assuming this isn't accounted for already in the 1.5 sample digital delay.

It remains to be seen whether this phase delay is good enough to lock the laser to the OMC cavity
  42   Wed Oct 31 23:55:17 2007 waldmanOtherOMCQPD tests
The 4 QPDs for the OMC have been installed in the 056 at the test setup. All 4 QPDs work and have medm screens located under C2TPT. The breadboard mounted QPDs are not very well centered so their signal is somewhat crappy. But all 4 QPDs definitely see plenty of light. I include light and dark spectra below. QPDs 1-2 are table-mounted and QPD 2 is labeled with a bit of blue tape. QDPs 3-4 are mounted on the OMC. QPD3 is the near field detector and QPD4 is the far field. In other words, QPD3 is closest to the input coupler and QPD4 is farthest.

Included below are some spectra of the QPDs with and without light. For QPDs 1 & 2, the light source is just room lights, while 3&4 have the laser in the nominal OMC configuration with a few mWs as source. The noise at 100 Hz is about 100 microvolts / rtHz. If I recall correctly, the QPDs have 5 kOhm transimpedance (right Rich?) so this is 20 nanoamps / rtHz of current noise at the QPD.
Attachment 1: QPD_SignalSpectrum.pdf
Attachment 2: QPD_SignalSpectrum.gif
  43   Thu Nov 1 01:28:04 2007 waldmanOtherOMCFirst digital lock of OMC
[Pinkesh, Sam]

We locked a fiber based NPRO to the suspended OMC tonight using the TPT digital control system. To control the laser frequency, we took the PZT AI output and ran it on a BNC cable down the hallway to the Thorlabs HV box. The Thorlabs is a singled ended unit so we connected the AI positive terminal only and grounded the BNC to the AI shield. We could get a -6 to 1.5 V throw in this method which fed into the 10 k resisotr + 9 V battery at the input of the HV box. The HV out ran to the NPRO PZT fast input.

We derived our error signal from a PDA255 in reflection with a 29.5 MHz PDH lock. The signal feeds into one of the unused Tip/Tilt AA channels and is passed to the PZT LSC drive through the TPT_PDH1 filter bank. In the PZT_LSC filter we put a single pole at 1 Hz which, together with the phase we mentioned the other night (180 degrees at 3 kHz) should allow a 1 kHz-ish loop. In practice, as shown below, we got a 650 Hz UGF with 45 degrees of phase margin and about 6 dB of gain margin.

The Lower figure shows the error point spectrum with 3 settings. REF0 in blue shows lots of gain peaking at 1.5 kHz-ish, just where its expected - the gain was -40. The REF1 has gain of -20 and shows no gain peaking. The current trace in red shows some gain peaking cuz the alignment is better but it also has included a 1^2:20^2 boost which totally crushes the low frequency noise. We should do a better loop sweep after getting the alignment right so we can see how much boost it will really take.

Just for fun, we are leaving it locked overnight and recording the PZT_LSC data for posterity.
Attachment 1: 071101_PZT_firstLoopSweep.pdf
Attachment 2: 071101_PZT_firstLoopSweep.gif
Attachment 3: 071101_OMC_FirstLock_spectra.pdf
Attachment 4: 071101_OMC_FirstLock_spectra.gif
  64   Mon Nov 5 22:24:38 2007 Andrey, SteveOmnistructureVACPumping down goes smoothly

We (Steve and Andrey) started pumping down at 3.25PM today. At 9 PM we turned off the rotary pump, and turned on turbomolecular pumps.

By 10.10PM we reached the pressure 1 milliTorr, and the current status is "Vacuum Normal". We leave the turbopumps on for the night, and as it is pretty late for Steve, we are going home.

P.S. Steve was very displeased with the standard selection of "Type" of messages, he would like to extend that list.
  79   Wed Nov 7 14:01:31 2007 waldmanOmnistructureOMCFrequency and Intensity noise
One of the biggest problems I had using the PZT to lock was excessive noise. I did a little noise hunting and found that the problem was the cable running from the rack to the laser fast input. As a reminder, the laser has a 4 MHz / volt fast input. We require about 300 MHz to go one FSR, so there is a Thorlabs HV box between at the NPRO fast input which takes 0-10 V -> 0-150 V. The 150 V HV range is worth about 600 MHz of NPRO frequency.

OLD SETUP: Single side of DAC differential (10 Vpp) -> 9V in series with 10 kOhm -> 10 kOhm input impedance of Thorlabs HV -> NPRO

We used the single side of the DAC differential because we didn't have a differential receiver. This turned out to be a bad idea because the cable picks up every 60 Hz harmonic known to man kind.

NEW SETUP: Digital conditioning -> DAC differential (digitally limited to 0 - 1 V) -> SR560 in A-B mode gain 10 (0 - 10 V output)-> Thorlabs HV -> NPRO.

This has almost no 60 Hz noise and works much, much better. Moral of the story, ALWAYS USE DIFFERENTIAL SIGNALS DIFFERENTIALLY !

Note that I may be saturating the SR560 with 10 V output, Its spec'd for 10 Vpp output with 1 VDC max input. I don't know whether or not it can push 10 V out....
  86   Fri Nov 9 00:01:24 2007 waldmanOmnistructureOMCOMC mechanical resonances (Tap tap tappy tap)
[Pinkesh, Aidan, Sam]

We did a tap-tap-tappy-tap test of the OMC to try to find its resonances. We looked at some combination of the PDH error signal and the DCPD signal in a couple of different noise configurations. The data included below shows tapping of the major tombstone objects as well the breadboard. I don't see any strong evidence of resonances below the very sharp resonance at 1300 Hz (which I interpret as the diving board mode of the breadboard). If I get free, I 'll post some plots of the different breadboard resonances you can excite by tapping in different places.

(The "normalized" tapping response is abs(tap - reference)./reference.)
Attachment 1: Fig1.png
Attachment 2: Fig2.png
Attachment 3: Fig4.png
Attachment 4: Fig2.pdf
Attachment 5: Fig1.pdf
Attachment 6: Fig4.pdf
Attachment 7: ResonanceData.zip
  99   Wed Nov 14 07:48:38 2007 nornaOmnistructureOMCOMC Cable dressing
[Snipped from an email]

1) Last Friday Pinkesh and I set the OMC up with only the top three OSEMs and took a vertical transfer function. We had removed the other OSEMs due to difficulty of aligning all OSEMs with the weight of the bench etc bringing the top mass lower than the tablecloth can accommodate. See attached TF.Clearly there are extra peaks (we only expect two with a zero in between) and my belief is that at least some of them are coupling of other degrees of freedom caused by the electrical wiring. Pinkesh and I also noticed the difficulty of maintaining alignment if cables got touched and moved around. So.....

2) Yesterday Dennis and I took a look at how much moving a cable bundle around (with the peak shielding) changed the DC alignment. In a not too precise experiment ( using HeNe laser reflecting off the bench onto a surface ~ 1 metre away) we saw that we could reposition the beam one or two mm in yaw and pitch. This corresponds to ~ one or two mrad which is ~ the range of the OSEM DC alignment. We discussed possibility of removing the cabling from the middle mass, removing the peak and taking it from the bench directly to the structure above. I asked Chub if he could make an equivalent bundle of wires as those from the two preamps to see what happens if we repeat the "moving bundle" experiment. So...

3) Today Chub removed the cabling going to the preamps and we replaced it with a mock up of wire bundle going directly from the preamps to the structure above. See attached picture. The wires are only attached to the preamp boxes weighted down with masses but the bundle is clamped at the top. We repeated the "wiggle the bundle" test and couldnt see any apparent movement ( so maybe it is at most sub-mm). The cable bundle feels softer.

The next thing Chub did was to remove the second bundle ( from photodiodes, heater, pzt) from its attachment to the middle mass and strip off the peek. It is now also going to the top of the structure directly. The whole suspension now appears freer. We discussed with Dennis the "dressing " of the wires. There are some minor difficulties about how to take wires from the bright side to the dark side, but in general it looks like that the wires forming the second "bundle" could be brought to the "terminal block" mounted on the dark side and from there looped up to the top of the structure. We would have to try all this of course to see the wiring doesnt get in the way of other things (e.g. the L and R OSEMs). However this might be the way forward. So...

4) Tomorrow Pinkesh and I will check the alignment and then repeat the vertical transfer function measurement with the two bundles as they are going from bench to top of structure. We might even do a horizontal one if the middle mass is now within range of the tablecloth.
We can then remove preamp cables completely and lay the second bundle of cables on the optical bench and repeat the TFs.

The next thing will be to weigh the bench plus cables. This will allow us to
a) work out what counterbalance weights are needed - and then get them manufactured
b) firm up on how to handle the extra mass in terms of getting the masses at the correct height.

And in parallel Chub will work on the revised layout of cabling.

Looking a little further ahead we can also get some stiffness measurements made on the revised bundle design ( using Bob's method which Alejandro also used) and fold into Dennis's model to get some sanity check the isolation.

I think that's it for now. Comments etc are of course welcome.

Attachment 1: OMC-11-13-07_011.jpg
Attachment 2: VerticalTrans.pdf
VerticalTrans.pdf VerticalTrans.pdf VerticalTrans.pdf VerticalTrans.pdf
  114   Mon Nov 19 14:19:25 2007 steveOmnistructurePEMjackhammer
The construction personal successfully jackhemmered a fence around the "Drever's parking slot"
There is no parking space available close by
Attachment 1: jackhammer.jpg
Attachment 2: jackhammer2.jpg
  122   Mon Nov 26 10:17:31 2007 steveOmnistructureSUSetmy sus damping restored
20 days plot is showing etmy loosing damping 4 times.
I zoomed in with each event. Three of them could of been triggered
by garbage loading just outside. However attachment 2 plot demonstrating that small earthquake or seismic event
did not tripped etmy damping.
The fourth event was preceded by a 4-5 hrs of continous rise of the rms motion at C1:SUS-ETMY_LLPD_VAR
Attachment 1: etmyrms20d.jpg
Attachment 2: etmyrmseq.jpg
  129   Wed Nov 28 08:47:29 2007 steveOmnistructureVACrga is out of order
The rga is not working since Nov 10
The controller is broken.
Attachment 1: pd65d23.jpg
  139   Thu Nov 29 11:10:54 2007 robOmnistructureVACRGAlogger sleeping
Without the RGA controller responding, the RGAlogger script just hangs. Rather than fix it, I just put it to sleep by commenting out the line in op440m crontab file. Once we get it running again, we'll move the cronjob to op340m.
  153   Sun Dec 2 17:37:33 2007 ranaOmnistructureComputersNetwork Cabling in the Office
We all know that we've spent many integrated man hours trying to figure out why our network connections
in the office area don't work. Usually its because of the bad hub around the Tobin/Osamu desk.

I pried open some of the wall conduit today and it looks pretty easy to fish cables through. I think
its time we finally did that. It may be a little disruptive, but I propose we get Larry to come over
and figure out what needs to happen for us to get regular 100 Mbit ports on the walls. These can
then all go over and get connected to a switch in the rack that holds linux1.

Opinions / comments ?
  179   Fri Dec 7 11:33:24 2007 waldmanOmnistructureOMCPZT wiring
The 2 pin LEMO connector has got an unmarked pin and a pin marked by a white half-circle.
The unmarked pin is connected to the side of the PZT attached to the mirror.
The marked pin is connected to the side of the PZT attached to the tombstone.
  188   Wed Dec 12 16:22:22 2007 albertoOmnistructureElectronicsLC filter for the RF-AM monitor circuit
In the LC configuration (see attached schematic) the resonant frequency is tuned to one of the peak of our RF-AM monitor and it is amplified by a factor equal to the Q of the filter. As I wrote in one of the last elog entries, we would like amplifications of about 10-30 dB in order to have negligible couplings. Such values are obtained only with small capacitances (few or less pF). The drawback is relatively large inductance (uH or more) which has inevitably low Self Resonant Frequencies (SRF - the resonant frequencies of the RLC circuit usually associated with an actual inductor - ~ MHz). Even before, one limit is also the input impedance of the RF amplifier. Quality factors > 1 require megaohms, far from the 50 ohms in the MiniCircuit amplifiers I’m using now. So, if we plan to use these even for the final design of the circuit, we have to abandon the LC configuration.
For this same reason the only way I could get the expected responses from my several test boards was with a 10 megaohm input probe (see attachment for the measurement with and without probe). Assuming that impedance, I found these as the best trade-offs between the attenuation requirements and the values of the inductors for respectively the peaks at 33, 66,133, 166,199 MHz:
26uH, 6.6u, 20u, 73u, 16u
If we could find inductor with these values and high SRF the configuration should work. The problem is I couldn’t find any. Above a few uH they all seem to have SRF ~ MHz.
That is why I switched to the Butterworth. This should work despite the input impedance of the amplifier and with much smaller inductances. I made a totally new test circuit, with surface mount components. I think I still have to fix some things in the measurements but (this time I got rid of the simulator I was using earlier and designed a new configuration with new values from the Horowitz’s tables) it seems I have the expected peaks. More soon.
Attachment 1: TF_LC_filter_10pF_1.8uH_scope_probe.png
Attachment 2: TF_LC_filter_10pF_1.8mH_no_probe.png
Attachment 3: LC_filter_schematic.png
  190   Thu Dec 13 12:05:36 2007 albertoOmnistructureElectronicsThe new Butterworth seems to work quite well
It works better probably because of the small inductors I'm using this time.
The peak is at 30 MHz because I didn't have the precise elements to get 33.

The bandwidth and the Q could be improved by adding one or two more order to the filter and trying to better match the low-pass' resonant frequency with the high-pass'.

Also I have to see if it could work at 166 and 199 MHz as well.
Attachment 1: TF_New_Butterworth_12-Nov-2007_TF.png
Attachment 2: Bultervverth2.png
  200   Wed Dec 19 11:31:01 2007 steveOmnistructurePEMaircond filter maintenance
Jeff is working on all air condiontion units of the 40m lab
This we do every six months.
Attachment 1: acfilters6m.jpg
  272   Sat Jan 26 02:08:53 2008 JohnOmnistructureLSCFibres
There is now a fibre running from the SP table to the ISCT at the Y-end. In the coming days I will try to mode match the beam from this fibre into the arm through ETMY. To achieve this I will be altering the optical layout of this table.
  310   Tue Feb 12 13:53:27 2008 robOmnistructureVACReturn of the RGA

The new RGA head was installed a few days ago. I just ran the RGAlogger script to see if it works, which it does. I also edited the crontab file on op340m to run the RGAlogger script every night at 1:25 AM. It should run tonight.
Attachment 1: RGA-080212.png
  365   Fri Mar 7 19:04:39 2008 steveOmnistructurePSLlaser pointer
Green laser pointer was found in my desk.
I blamed Rana for not returning it to me after a conference talk.
It is surprisingly bright still.
I will bring sweets for Wednesday meeting.
  453   Sat Apr 26 11:21:15 2008 ajwOmnistructureComputersbackup of /cvs/cds restarted
The backup of /cvs/cds (which runs as a cron job on fb40m; see /cvs/cds/caltech/scripts/backup/000README.txt) 
has been down since fb40m was rebooted on March 3.
I was unable to start it because of conflicting ssh keys in /home/controls/.ssh .
With help from Dan Kozak, we got it to work with both sets of keys
( id_rsa, which allows one to ssh between computers in our 113 network without typing a password,
 and backup2PB which allows the cron job to push the backup files to the archive in Powell-Booth).

It still goes down every time one reboots fb40m, and I don't have a solution.
A simple solution is for the script to send an email whenever it can't connect via ssh keys
(requiring a restart of ssh-agent with a passphrase), but email doesn't seem to work on fb40m.
I'll see if I can get help on how to have sendmail run on fb40m.
  464   Mon May 5 11:04:30 2008 robOmnistructureComputersNetwork setup

Mafalda was not connected to the network, and so our DMF-based seisBLRMS has not been running for ~1 week. I traced this to a broken ethernet cable connecting mafalda to the network switch in the rack next to the B&W printer. This cable has a broken connector at the switch side, which means it can't stay connected if there's any tension. It needs to be replaced.
  483   Fri May 16 17:27:55 2008 AndreyOmnistructureGeneralToilets are broken, do not use them !!!

Both toilets in 40-meter were constantly flushing, the leaking water was on the floor inside of the restrooms, so


I have heard the constant loud sound of flushing water, opened the door, and was unpleasantly surprised because all the floor was under the layer of water and the toilets were constantly flushing. I called security at X5000, a plumber came in and told that a team of plumbers needs to repair the flushing system after the weekend. The plumber today just shut off the flushing water, wiped off the floor and told not to use the restrooms in the weekend. We should expect a team of plumbers on Monday.

Sinks are working, so you can wash your hands.
  780   Fri Aug 1 11:51:15 2008 justingOmnistructureComputersadded /cvs/cds/site directory
I added a /cvs/cds/site directory. This is the same as is dicsussed here. Right now it just has the text file 'cit' in it, but eventually the other scripts should be added. I'll probably use it in the next version of mDV.
  885   Tue Aug 26 09:58:59 2008 steveOmnistructureCOCETMX is #03
This is the picture of ETMX from the upper south west viewport
Attachment 1: etmx-d40posg_012.jpg
Attachment 2: etmx03.jpg
  888   Tue Aug 26 18:19:16 2008 ranaOmnistructureElectronicsResistor Noise at the 40m
As Stefan points out in his recent ISS ilog entries at LLO, Daniel Sigg recently wrote a
recommendation memo on resistor and capacitor
choices: T070016.

While working on the PMC I have had to use leaded resistors and wondered about the noise. As it turns
out we have the RN series of 1/4 W resistors from Stackpole Electronics. The RN series are
metal film resistors (datasheet attached); metal film is what Sigg recommends for lowest flicker

So we are OK for using the Stackpole 1/4 W leaded resistors in low noise circuits.
Attachment 1: SEI-RN_RNM.pdf
  1038   Fri Oct 10 00:34:52 2008 robOmnistructureComputersFEs are down

The front-end machines are all down. Another cosmic-ray in the RFM, I suppose. Whoever comes in first in the morning should do the all-boot described in the wiki.
  1039   Fri Oct 10 10:20:42 2008 AlbertoOmnistructureComputersFEs are down


The front-end machines are all down. Another cosmic-ray in the RFM, I suppose. Whoever comes in first in the morning should do the all-boot described in the wiki.

Yoichi and I went along the arms turning off and on all the FE machines. Then, from the control room we rebooted them all following the procedures in the wiki. Everything is now up again.

I restored the full IFO, re-locked the mode cleaner.
  1040   Fri Oct 10 13:57:33 2008 AlbertoOmnistructureComputersProblems in locking the X arm
This morning for some reason that I didn't clearly understand I could not lock the Xarm. The Y arm was not a problem and the Restore and Align script worked fine.

Looking at the LSC medm screen something strange was happening on the ETMX output. Even if the Input switch for c1:LSC-ETMX_INMON was open, there still was some random output going into c1:LSC-ETMX_INMON, and it was not a residual of the restor script running. Probably something bad happened this monring when we rebooted all the FE computers for the RFM network crash that we had last night.

Restarting the LSC computer didn't solve the problem so I decided to reboot the scipe25 computer, corresponding to c1dcuepics, that controls the LSC channels.

Somehow rebooting that machine erased all the parameters on almost all medm screens. In particular the mode cleaner mirrors got a kick and took a while to stop. I then burtrestored all the medm screen parameters to yesterday Thursday October 9 at 16:00. After that everything came back to normal. I had to re-lock the PMC and the MC.

Burtrestoring c1dcuepics.snap required to edit the .snap file because of a bug in burtrestore for that computer wich adds an extra return before the final quote symbol in the file. That bug should be fixed sometime.

The rebooting apparently fixed the problem with ETMX on the LSC screen. The strange output is not present anymore and I was able to easily lock the X arm. I then run the Align and the Restore full IFO scripts.
  1070   Wed Oct 22 20:50:30 2008 AlbertoOmnistructureComputersGPS
Today I measured the GPS clock frequency at the output of CLOCK_MON in a board on the same crate where the c1iool0 computer is located. The monitor was connected with a BNC cable to the 10MHz reference input of the frequency counter on top of that rack, where it was used to check the 166MHz coming from one of the Marconi.

The frequency was supposed to be 10MHz but I actually measured 8 MHz. I tracked down the GPS input cable to the board and it turned out to come from one of the 1Y7 rack. Here it was connected to a board with a display that was showing corrupted digits, plus some leds on the front panel were red.

I'm not sure the GPS reference is working properly.
  1075   Thu Oct 23 18:45:18 2008 AlbertoOmnistructureComputer Scripts / ProgramsPython code for GPIB devices developed for the Absl length experiment
I wrote two Python scripts for my measurement that can be also used/imitated by others: sweepfrequency. py and HP8590.py. The first is is the one that we run by a Python interpreter (just typing "python <name script> <parameters>"from the terminal). It manages the parameters that we have to pass it for the measurement and calls the second one, HP8590.py which actually does most of the job.

Here what it does. It scans the frequency of the Marconi and, for each step, searches the highest peak in the Spectrum Analyzer (which is centered 50 KHz around the frequency of the Marconi). It then associates the amplitude of the peak to the frequency of the Marconi and write the two number in two columns of a file.
The file name, the GPIB-to/LAN interface IP address, the frequency range, the frequency step amplitude and the number of measures we want it to average for each step, are all set by the parameters when we call sweepfrequency.py.
More details are in the help of the function or just looking at the header of the code.

I guess that one can perform other similar measurement just with little changes in the code so I think it could turn out useful to anyone else.
Attachment 1: HP8590.py
# This function provides the measuremeent of the peak amplitude on the spectrum analyzer
# HP8590 analyzer while sweeping the excitation frequency on the function generator.
# Alberto Stochino 2008

import re
import sys
import math
from optparse import OptionParser
from socket import *
... 55 more lines ...
Attachment 2: sweepfrequency.py
## sweepfrequency.py [-f filename] [-i ip_address] [-a startFreq] [-z endFreq] [-s stepFreq] [-m numAvg]
## This script sweeps the frequency of a Marconi local oscillator, within the range
## delimited by startFreq and endFreq, with a step set by stepFreq. An arbitary
## signal is monitored on a HP8590 spectrum analyzer and the scripts records the
## amplitude of the spectrum at the frequency injected by the Marconi at the moment.

## The GPIB address of the Marconi is assumed to be 17, that of the HP Spectrum Analyzer to be 18

## Alberto Stochino, October 2008
... 51 more lines ...
  1135   Fri Nov 14 17:41:50 2008 JenneOmnistructureElectronicsSweet New Soldering Iron
The fancy new Weller Soldering Iron is now hooked up on the electronics bench.

Accessories for it are in the blue twirly cabinet (spare tips of different types, CD, and USB cable to connect it to a computer, should we ever decide to do so.

Rana: the soldering iron has a USB port?
Attachment 1: newSolderingIron.JPG
  1198   Sat Dec 20 23:37:43 2008 robOmnistructureGeneralSaturday Night Fever after presumed power failure

Just came by to pick something up...

... alarm handlers screeching...

... TP1 failure--closing V1... call Steve... Steve says ok till tomorrow...

... all front ends down (red)...

... all suspensions watchdogged...

... all (I think) servos off...

... PSL shutter closed ...

... chiller at 15C ... I turned it off to prevent condensation in PA...

... MOPA shutter closed... turned off key on Lightwave power supply

... good luck all, and happy holidays!
  1215   Sun Jan 4 13:17:23 2009 AlanOmnistructureComputer Scripts / ProgramsNew 40mWebStatus
I have set up some code in /cvs/cds/caltech/scripts/webStatus along with a cronjob on controls@nodus to generate a webStatus every half hour, at 40mWebStatus

you are welcome to add/delete lines corresponding to interesting EPICS channels, in the template /cvs/cds/caltech/scripts/webStatus/webStatus_template.html . The 2nd number is the "golden" value of the EPICS channel; it can be edited by hand, or one could copy a "golden" webStatus.html to webStatus_template.html . I think it's probably premature to automate this...

I noticed that Yoichi also has a cron job posting 40m medm screen snapshots. Very nice.

controls@nodus also runs a third cronjob, which checks if the nightly backup fails, and if so, sends an email to me.

I guess we need some kind of "official" crontab file for controls@nodus so that we know how/where to add things. So, I put one in /cvs/cds/caltech/crontab/controls@nodus.crontab
  1216   Mon Jan 5 11:21:05 2009 AlanOmnistructureComputer Scripts / ProgramsNew 40mWebStatus


I guess we need some kind of "official" crontab file for controls@nodus so that we know how/where to add things. So, I put one in /cvs/cds/caltech/crontab/controls@nodus.crontab

Alan and I agreed that we should edit the crontab by "crontab -e" command rather than editing the "official" crontab in /cvs/cds/caltech/crontab/.
After confirming that the new crontab works as expected, you are encouraged to make a copy of the new crontab into /cvs/cds/caltech/crontab/ as a backup.
Then do "svn ci" in the directory.
  1218   Thu Jan 8 20:26:17 2009 robOmnistructureGeneralEarthquake in San Bernardino
Magnitude 4.5

* Friday, January 09, 2009 at 03:49:46 UTC
* Thursday, January 08, 2009 at 07:49:46 PM at epicenter

Location 34.113°N, 117.294°W
Depth 13.8 km (8.6 miles)

* 2 km (1 miles) S (183°) from San Bernardino, CA
* 6 km (4 miles) NNE (25°) from Colton, CA
* 8 km (5 miles) E (89°) from Rialto, CA
* 88 km (55 miles) E (86°) from Los Angeles Civic Center, CA

Location Uncertainty horizontal +/- 0.3 km (0.2 miles); depth +/- 0.8 km (0.5 miles)
Parameters Nph=142, Dmin=1 km, Rmss=0.38 sec, Gp= 14°,
M-type=moment magnitude (Mw), Version=Q

I felt it from home.

All the watchdogs are tripped, vacuum normal. It looks like all the OSEM sensor values are swinging, so presumably no broken magnets. I'm leaving the suspensions off so we can take fine-res spectra overnight.

Watchout for crappy cables coming loose.
  1372   Mon Mar 9 10:59:05 2009 AlanOmnistructureComputersssh agent on fb40m restarted for backup

After the boot-fest, the nightly backup to Powell-Booth failed, and an automatic email got sent to me. I restarted the ssh agent, following the instructions in /cvs/cds/caltech/scripts/backup/000README.txt .

  1392   Thu Mar 12 00:29:39 2009 JenneOmnistructureDMFDMF being whiny again

The seisBLRMS has been running on megatron via an open terminal ssh'd into there from allegra with matlab running.

[Yoichi, Jenne]

seisBLRMS was down again. I assumed it was just because the DMF Master Enable was in the 'Disabled' state, but enabling it didn't do the trick. Rana's green terminal window was complaining about not being able to find nodus.ligo.caltech.edu. Yoichi and I stopped it, closed and restarted Matlab, ran mdv_config, then ran seisBLRMS again, and it seems happy now.

On the todo list still is making the DMF / seisBLRMS stuff happy all the time.
  1414   Fri Mar 20 15:54:29 2009 steveOmnistructureGeneral480V crane power switch on MEZ

CES Mezzanine is beeing rebuilt to accommodate our new neighbor: the 20ft high water slide...& .jacuzzi

All our ac power transformers are up there. Yesterday we labelled the power switch of 480VAC on the mezz

that we need to keep to run the 3 cranes in the lab.

  1453   Fri Apr 3 14:52:38 2009 JenneOmnistructurePEMGuralp is finally back!

After many, many "it'll be there in 2 weeks" from the Guralp people, our seismometer is finally back!

I have it plugged into the Guralp breakout box's Channel 1xyz (so I have unplugged the other Guralp).  Both of the Guralp's are currently sitting under the MC1/MC3 chamber.

Before we can have both Guralps up and running, I need to stuff the next 3 channels of the breakout box (back in the fall, I only had Caryn do 1x, 1y, 1z, and now I need 2x, 2y and 2z done with the fancy low-noise resistors), so all the gains match between the 2 sets of channels.

I'm leaving the new Guralp plugged in so we can see how it behaves for the next couple days, until I take out the breakout box for stuffing.

  1518   Fri Apr 24 16:24:25 2009 robOmnistructureVACPaschen

In response to Steve's elog entry, and for 40m posterity, I provide the Paschen Curve.

Attachment 1: paschens.png
Attachment 2: paschenplot.m
% Paschen Curve plotting

% From http://home.earthlink.net/~jimlux/hv/paschen.htm

% Breakdown voltage:
% Vbreakdown = B * p * d / (C + ln( p * d))
% Breakdown field strength:
% Ebreakdown = p * ( B / ( C + ln ( p * d)))
... 38 more lines ...
  1564   Fri May 8 10:05:40 2009 AlanOmnistructureComputersRestarted backup since fb40m was rebooted

Restarted backup since fb40m was rebooted.

  1594   Sun May 17 20:50:38 2009 robOmnistructureEnvironmentmag 5.0 earthquake in inglewood

2009 May 18 03:39:36 UTC

Earthquake Details

Magnitude 5.0
  • Monday, May 18, 2009 at 03:39:36 UTC
  • Sunday, May 17, 2009 at 08:39:36 PM at epicenter
Location 33.940°N, 118.338°W
Depth 13.5 km (8.4 miles)
  • 2 km (1 miles) E (91°) from Lennox, CA
  • 2 km (1 miles) SSE (159°) from Inglewood, CA
  • 3 km (2 miles) NNE (22°) from Hawthorne, CA
  • 7 km (4 miles) ENE (72°) from El Segundo, CA
  • 15 km (10 miles) SSW (213°) from Los Angeles Civic Center, CA
Location Uncertainty horizontal +/- 0.4 km (0.2 miles); depth +/- 0.9 km (0.6 miles)
Parameters Nph=139, Dmin=7 km, Rmss=0.42 sec, Gp= 40°,
M-type=local magnitude (ML), Version=C
Event ID ci10410337
  1613   Wed May 20 10:43:17 2009 steveOmnistructureEnvironmentaccelerometers sensitivity


2009 May 18 03:39:36 UTC

Earthquake Details

Magnitude 5.0
  • Monday, May 18, 2009 at 03:39:36 UTC
  • Sunday, May 17, 2009 at 08:39:36 PM at epicenter
Location 33.940°N, 118.338°W
Depth 13.5 km (8.4 miles)
  • 2 km (1 miles) E (91°) from Lennox, CA
  • 2 km (1 miles) SSE (159°) from Inglewood, CA
  • 3 km (2 miles) NNE (22°) from Hawthorne, CA
  • 7 km (4 miles) ENE (72°) from El Segundo, CA
  • 15 km (10 miles) SSW (213°) from Los Angeles Civic Center, CA
Location Uncertainty horizontal +/- 0.4 km (0.2 miles); depth +/- 0.9 km (0.6 miles)
Parameters Nph=139, Dmin=7 km, Rmss=0.42 sec, Gp= 40°,
M-type=local magnitude (ML), Version=C
Event ID ci10410337

 Wilcoxon 731A seismic accelerometers and Guralp CMG-40T-old seismometer at magnitude 5 and 4 erthquakes

Attachment 1: eq5m4.jpg
  1614   Wed May 20 16:03:52 2009 steveOmnistructureEnvironmentusing OSEMs to look at seismic activity

Rana suggested using OSEM sensing voltages as guide lines to look seismic activity.

As you see todays drilling and tumping activity was nothing compared to the EQ of mag 5 and 4

Optic level servos are turned back on.


What Steve means is that there is some drilling going on in the CES shop to accomodate the new water flume group. We want to

make sure that the mirrors don't move enough to break the magnets. On the dataviewer we should look to make sure that the

sensor channels stay between 0-2 V.     -Rana


Attachment 1: eqOSEM5m4.jpg
  1722   Wed Jul 8 11:13:36 2009 AlbertoOmnistructureComputerswireless router disconnected

Once again, this morning I found the wireless router disconnected from the LAN cable. No martian WiFi was available.

I wonder who is been doing that and for what reason.

  1731   Fri Jul 10 19:56:23 2009 rana, kojiOmnistructureEnvironmentChanged office temp

I have increased the temperature setpoint in the office area by ~0.75 deg F. Figure attached. Also a few days ago I increased the setpoint of the AC in the control room. Looks like the Laser is able to handle the changes in office area temperature so far, but lets see how it fares over the weekend.

Attachment 1: therm.JPG
  1732   Sun Jul 12 20:05:06 2009 ranaOmnistructureEnvironmentChanged office temp
This is a 7-day minute trend. There's no obvious effect in any of the channels looking back 2 days.

Seems like the laser chiller fix has made the laser much more immune to the office area temperature.
Attachment 1: Picture_3.png
  1734   Sun Jul 12 23:14:56 2009 JenneOmnistructureGeneralWeb screenshots aren't being updated

Before heading back to the 40m to check on the computer situation, I thought I'd check the web screenshots page that Kakeru worked on, and it looks like none of the screens have been updated since June 1st.  I don't know what the story is on that one, or how to fix it, but it'd be handy if it were fixed.

  1738   Mon Jul 13 15:48:05 2009 ranaOmnistructureEnvironmentRemoval of the cold air deflection device for the MOPA chiller
Around 2 PM today, I removed the blue flap which has been deflecting the cold air from the AC down into the laser chiller.
Let's watch the laser trends for a few days to see if there's any effect.
  1740   Mon Jul 13 23:03:14 2009 rob, albertoOmnistructureEnvironmentRemoval of the cold air deflection device for the MOPA chiller

Around 2 PM today, I removed the blue flap which has been deflecting the cold air from the AC down into the laser chiller.
Let's watch the laser trends for a few days to see if there's any effect.

Alberto has moved us to stage 2 of this experiment: turning off the AC.

The situation at the control room computers with the AC on minus the blue flap is untenable--it's too cold and the air flow has an unpleasant eye-drying effect.
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