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ID Date Authorup Type Category Subject
  11259   Mon Apr 27 09:09:15 2015 SteveUpdatePEMair cond filters checked

 

Quote:

 

Quote:

Yesterday morning was dusty. I wonder why?

The PRM sus damping was restored this morning.

Yesterday afternoon at 4 the dust count peaked 70,000 counts

Manasa's alergy was bad at the X-end yesterday. What is going on?

There was no wind and CES neighbors did not do anything.

Air cond filters checked by Chris. The 400 days plot show 3 bad peaks at 1-20, 2-5 & 2-19

  11260   Mon Apr 27 14:37:55 2015 SteveUpdateVACN2 pneumatic pressure watch

 

Quote:

Based on Jenne's chiara disk usage monitoring script, I made a script that checks the N2 pressure, which will send an email to myself, Jenne, Rana, Koji, and Steve, should the pressure fall below 60psi. I also updated the chiara disk checking script to work on the new Nodus setup. I tested the two, only emailing myself, and they appear to work as expected. 

The scripts are committed to the svn. Nodus' crontab now includes these two scripts, as well as the crontab backup script. (It occurs to me that the crontab backup script could be a little smarter, only backing it up if a change is made, but the archive is only a few MB, so it's probably not so important...)

This watch script gives little time to replace N2 cylinder. When the regulated supply drops below 60 psi the cylinder pressure is 60 psi too.

It is more of a statement that V1 is closed and act accordingly. It's only practical if you are in the lab.

Rana pointed it out correctly that we need this message 24 hrs before it happens. This requires monitoring  of total supplies , not the regulated one.

So we need pressure transducers on each nitrogen cylinder, before the regulator. The sum of the two N2 cylinder when they are full 4000 - 4500 psi

The first email should be send out at 1000 psi as sum of the two cylinders. This means that you have  1 day to replace nitrogen cylinder.

 Most of the time the daily consumption is 750 +-50 psi   

However sometimes  this variation goes up   ~750 +-150 psi

  11262   Tue Apr 28 09:49:26 2015 SteveUpdateVACVac Summery Channels

 

 

       Channel        

                    Function                                          Interlock action           
            

C1:Vac-P1_pressure   

 IFO vac envelope pressure           at 3 mT close V1 and PSL shutter
C1:Vac-P2_pressure  Maglev foreline pressure                      at 6 Torr close V1 
C1:Vac-P3_pressure  annuloses    
C1:Vac-CC1_pressure  IFO pressure   at 1e-5 Torr close VM1
C1:Vac-CC4_pressure  RGA  pressure    
 C1:Vac-N2pres  valve's drive  pneumatic 60-80PSI    

 

at 55 PSI close V1, at 45 PSI close all 
 It  does not exist yet 2 N2 cylinder sum pressure  

 

  11264   Thu Apr 30 16:30:25 2015 SteveUpdateVACN2 pneumatic pressure watch set up

We have 2 transduser PX303-3KG5V   http://www.omega.com/pressure/pdf/PX303.pdf They  will be installed on the out put of the N2 cylinders to read the supply pressure.

I will order one DC power supply  http://www.omega.com/pptst/PSU93_FPW15.html      PSU-93

One full cylinder pressure is ~ 2400 PSI max so two of them will give us ~9Vdc

The email reminder should be send at 1000 PSI  =  1.8 V

 

 

 

 

  11274   Tue May 5 16:02:57 2015 SteveUpdateVACVac Summery Channels with discription

As it was requested by the Bos.

It would be nice to read from the epic screen C1:Vac-state_mon.......Current State: Vacuum Normal, valve configuration

Quote:

       Channel        

                    Function                                              Description                                             Interlock         
             

C1:Vac-P1_pressure   

 Main volume of 40m interferro meter        P=Pirani gauge, Pressure range: ATM-760  to 1e-4 Torr at 3 mT close V1 and PSL shutter
C1:Vac-P2_pressure  Maglev foreline pressure

Maglev is the main pump of our vacuum system below 500 mTorr

It's long term pressure has to be <500 mTorr                  

 at 6 Torr close V1 
C1:Vac-P3_pressure  annuloses

 Each chamber has it's own annulos. These small volumes are indipendent from main volume.     Their  pressure  ranges are <5 mTorr at vac. normal valve configuration.

                                          
C1:Vac-CC1_pressure  IFO main volume

CC1=cold cathode gauge (low emmision), Pressure range: 1e-4 to 1e-10 Torr,

In vac- normal configuration CC1= 2e-6 Torr

at 1e-5 Torr close VM1
C1:Vac-CC4_pressure  RGA  pressure In vac-normal configuration CC1=CC4  
 C1:Vac-N2pres  valve's drive pneumatic    

The N2 supply is regulated to 60-80 PSI out put at the auto cylinder changer.

 at 55 PSI close V1, at 45 PSI close all 
 It  does not exist yet 2 N2 cylinder sum pressure

Each cylinder pressure will be measured before the regulator and summed for warning message to be send

at 1000 PSI

 

  11275   Fri May 8 08:16:46 2015 SteveUpdateLSCdrift in Y arm

Why is the Y arm drifting so much?

The " PSL FSS Slow Actuator Adjust " was brought back to range from 1.5 to 0.3 yesterday as ususual. Nothing else was touched.

I'm not sure if the timing scale is working correctly on theses summery plots. What is the definition of today?

The y-arm became much better as I noticed it at 5pm

 

  11276   Fri May 8 14:30:09 2015 SteveUpdateVACCC1 cold cathode gauges are baked now

CC1s  are not reading any longer. It is an attempt to clean them over the weekend at 85C

These brand new gauges "10421002" sn 11823-vertical, sn 11837 horizontal replaced 11 years old 421 http://nsei.missouri.edu/manuals/hps-mks/421%20Cold%20Cathode%20Ionization%20Guage.pdf  on 09-06-2012 http://nodus.ligo.caltech.edu:8080/40m/7441

Quote:

 

We have two cold cathode gauges at the pump spool and one  signal cable to controller. CC1  in horizontal position and CC1 in vertical position.  

CC1 h started not reading so I moved cable over to CC1 v

 

  11287   Tue May 12 14:57:52 2015 SteveUpdateVACCC1 cold cathode gauges are baked now

Baking both CC1 at 85 C for 60 hrs did not help.

The temperature is increased to 125 C and it is being repeated.

Quote:

CC1s  are not reading any longer. It is an attempt to clean them over the weekend at 85C

These brand new gauges "10421002" sn 11823-vertical, sn 11837 horizontal replaced 11 years old 421 http://nsei.missouri.edu/manuals/hps-mks/421%20Cold%20Cathode%20Ionization%20Guage.pdf  on 09-06-2012 http://nodus.ligo.caltech.edu:8080/40m/7441

Quote:

 

We have two cold cathode gauges at the pump spool and one  signal cable to controller. CC1  in horizontal position and CC1 in vertical position.  

CC1 h started not reading so I moved cable over to CC1 v

 

 

  11290   Wed May 13 13:33:34 2015 SteveFrogsPEMGuralp breakout box recovered

COD_Sugar napolion is due to Steve:  Item delivered, model CMG-SCU-0013, sn G9536

Quote:

Reward being offered for the safe return of this thing:

 

  11292   Fri May 15 16:18:28 2015 SteveUpdateVACVac Operation Guide

Vacuum Operation Guide is up loaded into the 40m-wiki. This is an old master copy. Not exact in terms of real action, but it is still a good guide of logic.

Rana has promissed to watch the N2 supply and change cylinder when it is empty. I will be Hanford next week.

  11324   Tue May 26 11:05:10 2015 SteveUpdatePEMworked around ETMY seism.

The cable tray holder cross beam is removed and cut short for good access to seismometer.

  11329   Thu May 28 10:42:19 2015 SteveUpdatePEMbad Guralp X-cable
Quote:

Tried swapping cables at the Guralp interface box side. It seems that all of our seismic signal problems have to do with the GUR2 cable being flaky (not surprising since it looks like it was patched with Orange Electrical tape!! rather than proper mechanical strain relief).

After swapping the cables today, the GUR2 DAQ channels all look fine: i.e. GUR1 (the one at the Y end) is fine, as is its cable and the GUR2 analog channels inside the interface box.

OTOH, the GUR1 DAQ channels (which have GUR2 (EX) connected into it) are too small by a factor of ~1000. Seems like that end of the cable will need to be remade. Luckily Jenne is still around this week and can point us to the pinout / instructions. Looks like there could be some shorting inside the backshell, so I've left it disconnected rather than risk damaging the seismometer. We should get a GUR1 style backshell to remake this cable. It might also be possible that the end at the seismometer is bad - Steve was supposed to swap the screws on the granite-aluminum plate on Thursday; I'll double check.

The Guralps were swapped.

What I did:   turned DC power off at 1X1,  hand carried them,  centered  each leveling bubbles, gently locked the jack screws and turned power back on.

ETMY at the east end now has CMG-T40-0008, sn T4157 as channel C1:PEM-SEIS_STS_1_Y_OUT_DQ.........

ETMX at south end now has CMG-T40-0053, sn T4Q17 as channel C1:PEM-SEIS_STS_2_Y_OUT_DQ.........

Conclusion:  Guralps are fine.  X  cable is bad. It was bad 6 months ago when it was made.

We can still swap the 3ft short cables at the granite base if Rana has not done it.

 

  11331   Thu May 28 16:43:52 2015 SteveUpdatePEMGuralps swapped

Koji and Steve,

The result: bad Guralp x-arm cable.

I will swap the short cables tomorrow at the base.

 

  11339   Mon Jun 1 08:32:14 2015 SteveUpdateSUSPRM damping restored

Local earthquake 3.8 Mag tripped only PRM

Vac monitor is not communicating.

PSL HEPA turned on
 

  11341   Mon Jun 1 15:22:19 2015 SteveUpdatePEMGuralps X- short cable is bad

 

Quote:

Koji and Steve,

The result: bad Guralp x-arm cable.

I will swap the short cables tomorrow at the base.

 

Short 46" long cables at the base plates were swapped. Their solderings looked horrible.

This cable actually worked at 5-5-2015

Bad cable at ETMY station now.  The new cable should be a little bit longer ~52"

  11344   Wed Jun 3 11:55:52 2015 SteveUpdateOptical LeversPRM-BS oplev

I'm getting ready change the Newport Ultima U100-AC to SS-Polaris-K1  LOW DRIFT MIRROR MOUNTS

Note: there is only one lens in the PRM lunching path (  only realized later ) , so the spots are large ~ 3 mm at PRM qpd and ~4.5 mm at BS qpd

The spots are well centered.

Atm3,  the spots were well centered yesterday ( the PRM is misaligned in pitch and retsore does not work today )


 

  11349   Tue Jun 9 10:57:12 2015 SteveUpdateSUS BS oplev laser tuned

Lenses removed from oplev beam path at elog entry 11246

 

  11352   Wed Jun 10 15:54:14 2015 SteveUpdateVACVacuum comp. rebooted

Koji and Steve succeded rebooting C1vac1, C1vac2 and pressure reading is working now

More tomorrow .........

 

  11354   Fri Jun 12 08:40:17 2015 SteveUpdateVACVacuum comp. rebooted

Koji and Steve,

One computer expert and one vacuum expert required.

Quote:

The serial connections to the vacuum gauges were recovered by rebooting c1vac1 and c1vac2.

Steve claimed that the vacuum screen had showed "NO COMM" at the vacuum pressure values.
The epics connection to c1vac was fine. We could logged in to c1vac1 with telnet too although c1vac2 had no response.

After some inspection, we decided to reboot the slow machines. Steve manually XXXed YYY valves (to be described)
to prepare for any possible unwanted switching. Initially Koji thought only c1vac2 can be rebooted. But it was wrong.
If the reset button is pushed, all of the modules on the same crate is reset. So everything was reset. After ~3min we still
don't have the connection to c1vac1 restored. We decided to another reboot. This time I pushed c1vac1 reset button.
After waiting about two minutes, the ADCs started to show green lights and the switch box started scanning.
We recovered the telnet connection to c1vac1 and epics functions. c1vac2 is still note responding to telnet, and
the values associated with c1vac2 are still blank.

Steve restored the valves and everything was back to normal.

Atm 1,  problem condition: gauges are not reading for a week, error message "NO COMM" and all computer LEDs are green

Atm 2, prepare to safe reboot:

            a, close V1, disconnect it's power cable and turn off Maglev, wait till rotation stops

            b, close PSL shutter ( take adrenaline if needed )

            c, close V4, V5, VA6 valves and disconnect their cables. "Moving" error message indicating this condition.

               V1 is not showing "Moving" because its power cable disconnected only! It will show it if its position indicator cable is disconnected too. There is no need for that.

               These valves closed and disabled will not allow accidental venting of main volume.

            d, push reset, reseting c1vac2 will reset c1vac1 also, wait ~ 6 minutes

"Vacuum Normal" valve configuration was restored after succesful reboot as follows:

             a, reconnect cable and open V4 and V5 at P2 & P3 <1e-1 Torr

             b, observe that P2  < 1e-3 Torr and retsart Maglev

             c, wait till Maglev reaches full speed of 560 Hz and reconnect-open V1

             d, reconnect-open VA6 at P3 <1e-3 Torr

NOTE: VM1 valve was locked in open position and it was not responding before and after reboot

          Error message on Atm2 is indicating this locked condition: "opening VM1 will vent IFO"

          This is a fauls message. The valve is frozen in open position. We need a softwear expert help.

 

 

  11369   Mon Jun 22 14:21:42 2015 SteveMetaphysicsTreasureJenne and Den graduated

Last supper before departing at  "Grazie" El Portal. All the best on your journey!

  11372   Tue Jun 23 11:18:20 2015 SteveUpdatePEMcleaning around chambers

Keven is our regular janitor is out for a few weeks.

The sub is careful- gentel Mario. We wiped arouind the vertex cambers north side on the floor and east arm racks.

 

  11373   Wed Jun 24 08:05:43 2015 SteveUpdatePSLlaser turned on

The laser went off around 11am yesterday. It was turned on

  11377   Thu Jun 25 15:07:50 2015 SteveUpdatesafetySurfs Safety 2015

Jessica Pena, Megan Kelly, Eve Chase and Ignacio Magana received 40m specific basic safety traning today.

  11387   Wed Jul 1 10:01:25 2015 SteveUpdateVACRGA scan pd78 day 275

 

 

  11388   Wed Jul 1 11:45:48 2015 SteveUpdatePEMcleaning around ETMX chamber
Quote:

Keven is our regular janitor is out for a few weeks.

The sub is careful- gentel Mario. We wiped arouind the vertex cambers north side on the floor and east arm racks.

 

Mario wiped the floor around the ETMX chamber today.

  11439   Thu Jul 23 15:41:41 2015 SteveUpdatePEMfitting ants with TERRO

Pasadena got 0.2" of  rain on Saturday. Temperatures were high with high humidity since than.The ants were back in the Control room east side benches.

We have started using TERRO Liquid Ant Baits in January 2015   This worked very well to this point.

Tree new packages were opened  yesterday and the ants are gone.

We can conclude that these baits must be replaced after 6 mounts.

The liquid baits contains BORAX  and it is safe.

 

  11443   Fri Jul 24 13:49:09 2015 SteveUpdatesafetyLock doors please !

Thursday morning I found the control room emergency exit not locked.

Please check the doors when leaving the lab , specially when you are the last one out.

  11451   Tue Jul 28 14:58:59 2015 SteveUpdateGeneraldo not place anything on optical table tops

angrySpecially heavy items: old analoge scope or hardware loaded boxes......etc

 The table cover section holding crossbars are not evenly spaced.no

You have to center each cover section on the cross bar so it is supported on both sides !

 

I will clean up on this table tomorrow

 

 

  11452   Tue Jul 28 15:05:09 2015 SteveUpdatesafetyfire alarm test ? no

We just had fire alarm trigged avacuation of the 40m lab.

It turned out that the CES building second floor sensor caused this action.

  11453   Tue Jul 28 15:06:27 2015 SteveUpdateIOOPSL HEPA turned on

crying

  11454   Tue Jul 28 16:42:25 2015 SteveUpdateGeneralJamies entry was deleted

Sorry Jamie, I accidentally deleted your elog entry #11453

  11459   Wed Jul 29 14:32:01 2015 SteveUpdateGeneralHow not to solder

 

Quote:

 

Quote:

Koji and Steve,

The result: bad Guralp x-arm cable.

I will swap the short cables tomorrow at the base.

 

Short 46" long cables at the base plates were swapped. Their solderings looked horrible.

This cable actually worked at 5-5-2015

Bad cable at ETMY station now.  The new cable should be a little bit longer ~52"

Koji could pull out easily 11 of the wires  from their socket.

  11464   Thu Jul 30 10:38:18 2015 SteveUpdatePEMY sesimostation is back on

Koji soldered new 50" long cable for the Y station.

 

  11469   Thu Jul 30 15:24:54 2015 SteveUpdatePEMY sesimostation is back on

Atm1,  New short-50" long cable was installed at ETMY end ( Y-station ) between Guralp-B ( MIT ) and granite base.

Interface box input 2 was left connected to cable 1 and input 1 to cable 2. This plot shows no change.

 

Atm2, Than I swapped the two long cables at the interface box

                                                                                                   Now the signal seems to be ok <2 Hz,

                                                                                                                                                       >2 Hz some problem exist.

      Channel Name Location Seismometer 40m long cable

Interfacebox input

 

 50" short cable

C1:PEM-RMS_GUR2X_.... ETMX Guralp -A  2   2                             Jenne's friend                
C1:PEM-RMS_GUR1X_.... ETMY  Guralp-B  1   1  Koji

I will look for more bad soldering tomorrow. How many cables did she make?

 

 

  11473   Fri Jul 31 10:36:22 2015 SteveUpdatePEMX seismo station short cable removed

 

Quote:

Atm1,  New short-50" long cable was installed at ETMY end ( Y-station ) between Guralp-B ( MIT ) and granite base.

Interface box input 2 was left connected to cable 1 and input 1 to cable 2. This plot shows no change.

 

Atm2, Than I swapped the two long cables at the interface box

                                                                                                   Now the signal seems to be ok <2 Hz,

                                                                                                                                                       >2 Hz some problem exist.

      Channel Name Location Seismometer 40m long cable

Interfacebox input

 

 50" short cable

C1:PEM-RMS_GUR2X_.... ETMX Guralp -A  2   2                             Jenne's friend                
C1:PEM-RMS_GUR1X_.... ETMY  Guralp-B  1   1  Koji

I will look for more bad soldering tomorrow. How many cables did she make?

 

 

We have to redo this cable also

  11476   Mon Aug 3 08:16:19 2015 SteveUpdateSUSETMX damping restored
  11483   Thu Aug 6 09:16:57 2015 SteveUpdateVACChiara gets new Ethernet card
  1. Yesterday we did put the vacuum system into safe to reboot mode  for the ethernet card swap.
  2. Atm1, IFO pressure
  3. Atm2, as prepared valve configuration where " moving " means closed and disconnected

 

  11487   Mon Aug 10 15:25:05 2015 SteveUpdatePEMwasp nest

The wasp nest will be removed tomorrow from from the out side of the east arm window.

The resonant frequency of the newly arrived gravity bee detector is not known.
 

  11505   Fri Aug 14 09:07:45 2015 SteveUpdatePEMGur interface box is wonky

Atm1, Before cable swap

Atm2, The long cables were swapped at the input of the interface box.

We can conclude that the problem is in the interface box

I wonder if interface box input 3 is wired?

  11514   Tue Aug 18 11:16:17 2015 SteveUpdatePEMGur interface box is wonky

The Guralp ADC  interface box  D060506 is ready for inspection. It is in front of 1X1 with open top and running.cool

Obviously c7 as 1 miroF cap is missing.blush

Quote:

Let's dismantle the I/F unit from the rack and connect the cable with the lid open.
We need to trace the signal.

 

  11517   Wed Aug 19 07:58:25 2015 SteveUpdatePEMGur interface box

Koji and Steve,

We took transferfunctions of each channel yesterday. They were identical ?. I will check the cables from ADC to DAQ next.

  11522   Fri Aug 21 08:38:37 2015 SteveUpdateIOOPMC locked

PMC needed to be locked manually.cheeky

  11523   Fri Aug 21 17:15:13 2015 SteveUpdatePEMGur interface box

 

Quote:

As reported previously, the transfer functions of the channels look fine. (i.e. All channels almost identical.)
I checked the chain from the unit input to the DAQ BNC connectors. They were all OK.

Today I have been checking the signals on the unit with the long DB37 cables connected.
I could not see anything on the Gur2 channels on the board. I looked at the DB37 for Gur2 and felt something is wrong.

I opened the housing of the cable and realized that all the pins are not fully inserted.
The wires were crimped improperly and prevents them to be fully inserted.

=> We need to redo the crimping to insert them.
=> We need to check the other side too.

I'm making a new long cable. Both connector ends of this X arm long cable were terrible. It was removed from the cable tray yesterday.

The Y arm Guralp is running fine. The interface box is open in front of 1X1 on a cart and it is alive!    Please be aware of it !

  11531   Tue Aug 25 16:39:06 2015 SteveUpdatesafetysafety training

Alessandra Marrocchesi received 40m specific basic safety training yesteday.

  11537   Fri Aug 28 17:04:12 2015 SteveUpdatePEMGur interface box cable
Ara! Onara suru tsu-mori datta keh-do, un-chi ga de-chatta...
Quote:

 

Quote:

As reported previously, the transfer functions of the channels look fine. (i.e. All channels almost identical.)
I checked the chain from the unit input to the DAQ BNC connectors. They were all OK.

Today I have been checking the signals on the unit with the long DB37 cables connected.
I could not see anything on the Gur2 channels on the board. I looked at the DB37 for Gur2 and felt something is wrong.

I opened the housing of the cable and realized that all the pins are not fully inserted.
The wires were crimped improperly and prevents them to be fully inserted.

=> We need to redo the crimping to insert them.
=> We need to check the other side too.

I'm making a new long cable. Both connector ends of this X arm long cable were terrible. It was removed from the cable tray yesterday.

The Y arm Guralp is running fine. The interface box is open in front of 1X1 on a cart and it is alive!    Please be aware of it !

The new cable was made this way:

Pins were located with ohm meter for locations and both ends were cut off.The Belden 1424A cable than was soldered to DB37 and Guralp circular connector " IKPT06F16-26S-ND "

This cable will connect the ADC interface box CCD# DO 60506 to Guralp seismometer at the sout end.

The Guralp's each 3 axies will be connected through a twisted pair to the differential input op amp

Gur  ouput  vertical axis + -  on circular connector   A, B  to DB37 pin 1 &20

Gur output        N/S axis + -  on circular connector   C, D to DB37 pin 2 & 21

Gur output       E/W axis + -  on circular connector   E, F to DB37 pin 3 & 22

Power +12 VDC  from DB37 pin 29 to Gur circular connector pin c (lower case)

Power -12 VDC  from DB37 pin 24 to Gur circular connector pin  M Note: this connection was absent at the first test of this cable!

Ground              from DB37 pin 10 to Gur circular connector pin b (lower case)

Summery: I may destored the opamp  at the Guralp A at the south end.

 

 

  11554   Tue Sep 1 10:36:06 2015 SteveUpdatePEMGurs swapped
Quote:

To help find out if Steve really melted the inside of our precious seismometer, lets hook it up using the handheld seismo wand and see if it produces volts when we shake the ground.

Also, please stop using names like GurA or Gur1 or GurSuzy. We have GurX and GurY because they are at those ends. Anything else is confusing.

I moved Gur A from ETMX to ETMY . Gur B at ETMY was disconnected and its cable  connected to Gur A

It seems that Gur A is alive. I will stop using A and B names after we stop swapping components.

  11566   Thu Sep 3 08:53:55 2015 SteveUpdateSUSETMY Oplev laser power is falling

Rana, Steve

We investigated the ETMY oplev table set up and did not find a red herring.

Two 2 years  vs one day plot below.

ps: thanks  Q for fixing  DTT, the auto scaling is not working at sampling rate 10 min and 1 hr period?? surprise

 

  11575   Fri Sep 4 09:36:48 2015 SteveUpdateLSCIR beatnote confusion.....

 

Quote:

I was thinking that the "FOSC" product line (which is called a "coupler" instead of a "splitter/combiner") was what we wanted. 

Koji brought to my attention that the 90/10 splitters we already have are of this line. So, I rigged a few up to shine a hopefully beating pair of fields on the fiber coupled thorlabs PD. 

I was able to get ~80uW each of PSL and AUX X light on the PD, which produced a -10dBm beatnoteyes Thus, I think these FOSC splitters are indeed what we want. 

I then threw this IR beatnote at our ALS signal chain. The beatnote was too big to throw through our ~+27dB RF amps, so I just sent the -10dBm over to the LSC rack.

The IR beat spectrum is somwhat noisier from 10-100Hz, but, more interesting, is that the sub-4Hz noise is identical in the two beats, and very coherent. This excludes ALS noise arising from anything happening in the green beat optics on the PSL table.

Obviously, the high frequency noise is largely the same and coherent too, but also coherent with the AUX X PDH control signal, so it is understood. 

FOSC-2-64-50-L-1-H64F-2
Single mode coupler, 2x2, 1064nm +/-20nm, 50/50 ratio, 900micron loose tube jacket, Hi1060flex fiber, 1m fiber length, FC/APC connectors

Four of these items ordered yesterday from http://afwtechnologies.com.au/sm_coupler.html

  11576   Fri Sep 4 10:25:19 2015 SteveConfigurationIOOAOM stage is ready

New stage can hold the correct polarization.

DRAWING CORRECTION:  Post block height was lowered to be 1.88" from 2.0"

  11591   Fri Sep 11 10:56:47 2015 SteveUpdateendtable upgradeETMY optical table feedthrough

The ETMY enclosure feedthrough - north is installed. The sealing material is hard to work with.

The upper empty blocks will be replaced by something soft to make changing cables easy.

 

ELOG V3.1.3-