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ID Date Author Type Category Subjectup
  8908   Tue Jul 23 16:39:31 2013 KojiUpdateGeneralFull IFO alignment recovered

[Annnalisa Koji]

Full alignment of the IFO was recovered. The arms were locked with the green beams first, and then locked with the IR.

In order to use the ASS with lower power, C1:LSC-OUTPUT_MTRX_9_6 and C1:LSC-OUTPUT_MTRX_10_7 were reduced to 0.05.
This compensates the gain imbalance between TRX/Y siganls and the A2L component in the arm feedback signals.

Despite the IFO was aligned, we don't touch the OPLEVs and green beams to the vented IFO.

Attachment 1: alignment.png
alignment.png
  8912   Tue Jul 23 20:41:40 2013 gautamConfigurationendtable upgradeFull range calibration and installation of PZT-mounted mirrors

 Given that the green beam is to be used as the reference during the vent, it was decided to first test the PZT mounted mirrors at the X-endtable rather than the Y-endtable as originally planned. Yesterday, I prepared a second PZT mounted mirror, completed the full range calibration, and with Manasa, installed the mirrors on the X-endtable as mentioned in this elog. The calibration constants have been determined to be (see attached plots for aproximate range of actuation):

M1-pitch: 0.1106 mrad/V

M1-yaw: 0.143 mrad/V

M2-pitch: 0.197 mrad/V

M2-yaw: 0.27 mrad/V


Second 2-inch mirror glued to tip-tilt and mounted:

  • The spot sizes on the steering mirrors at the X-end are fairly large, and so two 2-inch steering mirrors were required.
  • The mirrors already glued to the PZTs were a CVI 2-inch and a Laseroptik 1-inch mirror.
  • I prepared another Laseroptik 2-inch mirror (45 degree with HR and AR coatings for 532 nm) and glued it to a PZT mounted in a modified mount as before.
  • Another important point regarding mounting the PZTs: there are two perforated rings (see attached picture) that run around the PZT about 1cm below the surface on which the mirror is to be glued. The PZT has to be pushed in through the mount till these are clear of the mount, or the actuation will not be as desired. In the first CVI 2-inch mirror, this was not the the case, which probably explains the unexpectedly large pitch-yaw coupling that was observed during the calibration [Thanks Manasa for pointing this out]. 

Full range calibration of PZT:

Having prepared the two steering mirrors, I calibrated them for the full range of input voltages, to get a rough idea of whether the tilt varied linearly and also the range of actuation. 

Methodology:

  • The QPD setup described in my previous elogs was used for this calibration. 
  • The linear range of the QPD was gauged to be while the output voltage lay between -0.5V and 0.5V. The calibration constants are as determined during the QPD calibration, details of which are here.
  • In order to keep the spot always in the linear range of the QPD, I stared with an input signal of -10V or +10V (ie. one extreme), and moved both the X and Y micrometers on the translational stage till both these coordinates were at one end of the linear range (i.e -0.5V or 0.5V). I then increased the input voltage in steps of ~1V through the full range from -10V to +10V DC. The signal was applied using a SR function generator with the signal amplitude kept to 0, and a DC offset in the range -5V to 5V DC, which gave the desired input voltages to the PZT driver board (between -10V DC and 10V DC).
  • When the output of the QPD amp reached the end of the linear regime (i.e 0.5V or -0.5V), I moved the appropriate micrometer dial on the translational stage to take it to the other end of the linear range, before continuing with the measurements. The distance moved was noted. 
  • Both the X and Y coordinates were noted in order to investigate pitch-yaw coupling.

Analysis and remarks:

  • The results of the calibration are presented in the plots below. 
  • Though the measurement technique was crude (and maybe flawed because of a possible z-displacement while moving the translational stage), the calibration was meant to be rough, and I think the results obtained are satisfactory. 
  • Fitting the data linearly is only an approximation, as there is evidence of hysteresis. Also, PZTs appear to have some drift, though I have not been able to quantify this (I did observe that the output of the QPD amp shifted by an amount equal to ~0.05mm while I left the setup standing for an hour or so).  
  • The range of actuation seems to be different for the two PZTs, and also for each degree of freedom, though the measured data is consistent with the minimum range given in the datasheet (3.5 mrad for input voltages in the range -20V to 120V DC). 

 

PZT Calibration Plots

The circles are datapoints for the degree of freedom to which the input is applied, while the 'x's are for the other degree of freedom. Different colours correspond to data measured with the position of the translational stage at some value.

                                            M1 Pitch                                                                                             M1 Yaw

M1_Pitch_calib.pdf     M1_Yaw_calib.pdf

 

                                              M2 Pitch                                                                                        M2 Yaw 

M2_Pitch_calib.pdf     M2_Yaw_calib.pdf

 



Installation of the mirrors at the X-endtable:

The calibrated mirrors were taken to the X-endtable for installation. The steering mirrors in place were swapped out for the PZT mounted pair. Manasa managed (after considerable tweaking) to mode-match the green beam to the cavity with the new steering mirror configuration. In order to fine tune the alignment, Koji moved ITMx and ETMx in pitch and yaw so as to maximise green TRX. We then got an idea of which way the input pointing had to be moved in order to maximise the green transmission.

 

Attachment 5: PI_S330.20L.pdf
PI_S330.20L.pdf
  8967   Mon Aug 5 18:48:44 2013 gautamConfigurationendtable upgradeFull range calibration of PZT mounted mirrors for Y-endtable

 I had prepared two more PZT mounted mirrors for the Y-end some time back. These are:

  • A 2-inch CVI mirror (45 degree, HR and AR for 532nm, was originally one of the steering mirrors at the X-endtable, and was removed while switching those out for the PZT mounted mirrrors).
  • A 1-inch Laseroptik mirror (45 degree, HR and AR for 532nm).

I used the same QPD set-up and the methodology described here to do a full-range calibration of these PZTs. Plots attached. The calibration constants have been determined to be:

CVI-pitch: 0.316 mrad/V

CVI-yaw:  0.4018 mrad/V

Laseroptik pitch: 0.2447 mrad/V

Laseroptik yaw:  0.2822 mrad/V

Remarks:

  • These PZTs, like their X-end counterparts, showed evidence of drift and hysteresis. We just have to deal with this.
  • One of the PZTs (the one on which the CVI mirror is mounted) is a used one. While testing it, I thought that its behaviour was a little anomalous, but the plots do not seem to suggest that anything is amiss.

Plots:

                                                        CVI YAW                                                                                                                         CVI PITCH

2-inch-CVI-Yawcalib.pdf      2-inch-CVI-Pitchcalib.pdf

                                                        Laseroptik YAW                                                                                                             Laseroptik PITCH

1-inch-Laseroptik-Yawcalib.pdf   1-inch-Laseroptik-Pitchcalib.pdf

 

  2279   Tue Nov 17 10:09:57 2009 josephbUpdateEnvironmentFumes

The smell of diesel is particularly bad this morning.  Its concentrated enough to be causing me a headache.  I'm heading off to Millikan and will be working remotely on Megatron.

  6191   Thu Jan 12 11:08:23 2012 Leo SingerUpdatePEMFunky spectrum from STS-2

I am trying to stitch together spectra from seismometers and accelerometers to produce a ground motion spectrum from Hz to 100's of Hz.  I was able to retrieve data from two seismometers, GUR1 and STS_1, but not from any of the accelerometers.  The GUR1 spectrum is qualitatively similar to other plots that I have seen, but the STS_1 spectrum looks strange: the X axis spectrum is falling off as ~1/f, but the Y and Z spectra are pretty flat.  All three axes have a few lines that they may share in common and that they may share with GUR1.

See attached plot.

Attachment 1: spectrum.jpg
spectrum.jpg
  932   Fri Sep 5 09:56:14 2008 josephb, EricConfigurationComputersFunny channels, reboots, and ethernet connections
1) Apparently the I00-ICS type channels had gotten into a funny state last night, where they were showing just noise, exactly when Rana changed the accelerometer gains and did major reboots. A power cycle of the c1ioo crate and appropriate restarts fixed this.

2) c1asc looks like it was down all night. When I walked out to look at the terminal, it claimed to be unable to read the input file from the command line I had entered the previous night ( < /cvs/cds/caltech/target/c1asc/startup.cmd). In addition we were unable to telnet in, suggesting an ethernet breakdown and inability to mount the appropriate files. So we have temporarily run a new cat6 cable from the c1asc board to the ITMX prosafe switch (since there's a nice knee high cable tray right there). One last power cycle and we were able to telnet in and get it running.
  687   Thu Jul 17 00:59:18 2008 JenneSummaryGeneralFunny signal coming out of VCO
While working on calibrating the MC_F signal, Rana and I noticed a funny signal coming out of the VCO. We expect the output to be a nice sine wave at about 80MHz. What we see is the 80MHz signal plus higher harmonics. The reason behind the craziness is to be determined. For now, here's what the signal looks like, in both time and frequency domains.

The first plot is a regular screen capture of a 'scope. The second is the output of the SR spectrum analyzer, as seen on a 'scope screen. The leftmost tall peak is the 80MHz peak, and the others are the harmonics.
Attachment 1: VCOout_time.PNG
VCOout_time.PNG
Attachment 2: VCOout_freq.PNG
VCOout_freq.PNG
  9583   Tue Jan 28 22:24:46 2014 ericq UpdateGeneralFurther Alignment

[Masasa, ericq]

Having no luck doing things remotely, we went into the ITMX chamber and roughly aligned the IR beam. Using the little sliding alignment target, we moved the BS to get the IR beam centered on ITMX, then moved ITMX to get good michelson fringes with ITMY. Using an IR card, found the retroflection and moved ETMX to make it overlap with the beam transmitted through the ITM. With the PRM flashing, X-arm cavity flashes could be seen. So, at that point, both the y-arm and x-arm were flashing low order modes. 

  12107   Thu May 5 14:03:52 2016 ericqUpdateLSCFurther Aux X PDH tweaks

This morning I poked around with the green layout a bit. I found that the iris immediately preceding the viewport was clipping the ingoing green beam too much, opening it up allowed for better coupling to the arm. I also tweaked the positions of the mode matching lenses and did some alignment, and have since been able to achieve GTRX values of around 0.5.

I also removed the 20db attenuator after the mixer, and turned the servo gain way down and was able to lock easily. I then adjusted the gain while measuring the CLG, and set it where the maximum gain peaking was 6dB, which worked out to be a UGF of around 8kHz. On the input monitor, the PDH horn-to-horn voltage going into the VGA is 2.44V, which shouldn't saturate the G=4 preamp stage of the AD8336, which seems ok.

The ALS sensitivity is now approaching the good nominal state:

There remains some things to be done, including comprehensive dumping of all beams at the end table (especially the reflections off of the viewport) and the new filters to replace the current post-mixer LPF, but things look pretty good.

Attachment 1: 2016-05-05_newals.pdf
2016-05-05_newals.pdf
  4581   Thu Apr 28 12:25:11 2011 josephbUpdateCDSFurther adventures in Hyper-threading

First, I disabled front end starts on boot up, and brought c1sus up.  I rebuilt the models for the c1sus computer so they had a new specific_cpu numbers, making the assumption that 0-1 were one real core, 2-3 were another, etc.

Then I ran the startc1SYS scripts one by one to bring up the models.  Upon just loading the c1x02 on "core 2" (the IOP), I saw it fluctuate from about 5 to 12.  After bringing up c1sus on "core 3", I saw the IOP settle down to about 7 consistently.  Prior to hyper-threading it was generally 5. 

Unfortunately, the c1sus model was between 60 and 70 microseconds, and was producing error messages a few times a second

[ 1052.876368] c1sus: cycle 14432 time 65; adcWait 0; write1 0; write2 0; longest write2 0
[ 1052.936698] c1sus: cycle 15421 time 74; adcWait 0; write1 0; write2 0; longest write2 0

Bringing up the rest of the models (c1mcs on 4, c1rfm on 5, and c1pem on 6), saw c1mcs occasionally jumping above the 60 microsecond line, perhaps once a minute.   It was generally hovering around 45 microseconds.  Prior to hyper-threading it was around 25-28 microseconds.

c1rfm was rock solid at 38, which it was prior to hyper-threading.  This is most likely due to the fact it has almost no calculation and only RFM reads slowing it down.

c1pem continued to use negligible time, 3 microseconds out of its 480.

I tried moving c1sus to core 8 from core 3, which seemed to bring it to the 58 to 65 microsecond range, with long cycles every few seconds.

 

I built 5 dummy models (dua on 7, dub on 9, duc on 10, dud on 11, due on 1) to ensure that each virtual core had a model on it, to see if it helped with stabilizing things.  The models were basically copies of the c1pem model.

Interestingly, c1mcs seemed to get somewhat better and only taking to 30-32 microseconds, although still not as good as its pre-hyper-threading 25-28.  Over the course of several minutes it was no longer having a long cycle.

c1sus got worse again, and was running long cycles 4-5 times a second.

 

At this point, without surgery on which models are controlling which optics (i.e. splitting the c1sus model up) I am not able to have hyper-threading on and have things working.  I am proceeding to revert the control models and c1sus computer to the hyper-threading state.

 

 

  13741   Mon Apr 9 18:46:03 2018 gautamUpdateIOOFurther debugging
  1. I analyzed the data from the free swinging MC test conducted over the weekend. Attachment #1 shows the spectra. Color scheme is same for all panels.
    • I am suspicious of MC3: why does the LR coil see almost no Yaw motion?
    • The "equilibrium" values of all the sensor signals (at the IN1 of the coil input filters) are within 20% of each other (for MC3, but also MC1 and MC2).
    • The position resonance is also sensed more by the side coil than by the LR coil.
    • To rule out satellite box shenanigans, I just switched the SRM and MC3 satellite boxes. But coherence between frequency noise as sensed by the arms remain.
  2. I decided to clean up my IMC nosie budget a bit more.
    • Attachment #2 shows the NB as of today. I'll choose a better color palette for the next update.
    • "Seismic" trace is estimated using the 40m gwinc file - the MC2 stack is probably different from the others and so it's contribution is probably more, but I think this will suffice for a first estimate.
    • "RAM" trace is measured at the CM board input, with MC2 misaligned.
    • The unaccounted noise is evident from above ~8 Hz.
    • More noises will be added as they are measured.
    • I am going to spend some time working on modeling the CM board noise and TF in LTspice. I tried getting a measurement of the transfer function fron IN1 to the FAST output of the CM board with the SR785 (motivation being to add the contribution of the input referred CM board noise to the NB plot), but I suspect I screwed up something w.r.t. the excitation amplitude, as I am getting a totally nonsensical shape, which also seems to depend on my input excitation amplitude. I don't think the output is saturated (viewed during measurement on a scope), but perhaps there are some subtle effects going on.
Attachment 1: MC_Freeswinging.pdf
MC_Freeswinging.pdf
Attachment 2: IMC_NB_20180409.pdf
IMC_NB_20180409.pdf
  13744   Tue Apr 10 14:28:44 2018 gautamUpdateIOOFurther debugging

I am working on IMC electronics. IMC is misaligned until further notice.

  2654   Thu Mar 4 02:25:14 2010 JenneUpdateCOCFurther details on the magnet story, and SRM guiderod glued

[Koji, Jenne]

First, the easy story:  SRM got it's guiderod & standoff glued on this evening.  It will be ready for magnets (assuming everything is sorted out....see below) as early as tomorrow.  We can also begin to glue PRM guiderods as early as tomorrow.

The magnet story is not as short.....

Problem: ITMX and ITMY's side magnets are not glued in the correct places along the z-axis of the optic (z-axis as in beam propagation direction). 

ITMX (as reported the other day) has the side magnet placement off by ~2mm.  ITMX side was glued using the magnet fixture from MIT and the teflon pads that Kiwamu and I improvised.

It was determined that the improvised teflon pads were too thin (maybe about 1m thick), so I took those out, and replaced them with the teflon pads stolen from the 40m's magnet gluing fixture.   (The teflon pad from the MIT fixture and the ones from the MIT fixture are the same within my measuring ability using a flat surface and feeling for a step between them.  I haven't yet measured with calipers the MIT pad thickness).  The pads from the 40m fixture, which were used in the MIT fixture to glue ITMY side last night were measured to be ~1.7mm thick.

Today when Koji hung ITMY, he discovered that the side magnet is off by ~1mm.  This improvement is consistent with the switching of the teflon pads to the ones from the 40m fixture.

We compared the 40m fixture with the one from MIT, and it looks like the distance from the edge of where the optic should sit to the center of the hole for the side magnet is different by ~1.1mm.  This explains the remaining ~1mm that ITMY is off by. 

We should put the teflon pads back into the 40m fixture, and only use that one from now on, unless we find an easy way to make thicker teflon pads for the fixture we received from MIT.  (The pads that are in there are about the maximum thickness that will fit).  I'm going to use my thickness measurements of SRM (taken in the process of gluing the guiderods) to see what thickness of pads / what fixture we want to actually use, but I'm sure that the fixture we found in the 40m is correct.  We can't use this fixture however, until we get some clean 1/4-28 screws.  I've emailed Steve and Bob, so hopefully they'll have something for us by ~lunchtime tomorrow. 

The ITMX side magnet is so far off in the Z-direction that we'll have to remove it and reglue it in the correct position in order for the shadow sensor to do anything.  For ITMY, we'll check it out tomorrow, whether the magnet is in the LED beam at all or not.  If it's not blocking the LED beam enough, we'll have to remove and reglue it too. 

Why someone made 2 almost identical fixtures, with a 1mm height difference and different threads for the set screws, I don't know.  But I don't think whoever that person was can be my friend this week. 

  12507   Mon Sep 19 22:03:10 2016 ericqUpdateGeneralFurther recovery progress

[ericq, Lydia, Teng]

Brief summary of this afternoon's activities:

  • PMC alignment adjusted (Transmission of 0.74)
  • IMC locked, hand aligned. Tranmission slightly over 15k. Measured spot positions to be all under 2mm.
  • Set DC offsets of MC2 Trans + WFS1 + WFS2 (WFS2 DC offsets had wandered so much that DC "centered" left some quadrants almost totally dark)
  • Set demod offsets of WFS1+WFS2
    • Note to self: WFS script area is a mess. I can never remember which scripts are the right ones to run. I should clean this up
  • WFS loops activated, tested. All clear.
  • Locked Yarm, dither aligned. Transmission 0.8
  • Moved BS to center ITMY reflection on AS camera
  • Misaligned ETMY, aligned PRM to make a flashing PRY AS beam. REFL camera spot confirmed to be on the screen, which is nice
  • Wandered ITMX around until its AS spot was found. ITMX OSEMs not too far from their half max. (todo: update with numbers)
  • Wandered SRM around until full DRMI flashes seen
  • Centered all vertex oplevs
  • Made a brief attempt at locking X arm, could only get some crazy high order mode to lock. BS and ITMX alignments have changed substantially from the in-air locks, so probably need to adjust ETMX much more.

Addendum: I had a suspicion that the alignment had moved so much, we were missing the TRX PDs. I misaligned the Y arm, and used AS110 as a proxy for X arm power, as we've done in the past for this kind of thing. Indeed, I could maximize the signal and lock a TM00 mode. Both the high gain PD and QPD in the TRX path are totally dark. This needs realignment on the end table.

  12508   Tue Sep 20 10:45:06 2016 ranaUpdateGeneralFurther recovery progress

Rana suspicious. We had arms locked before pumpdown with beams on Transmon PDs. If they're off now, must be beams are far off on the mirrors. Try A2L to estimate spot positions before walkin the beams too far.

  12510   Wed Sep 21 01:08:02 2016 ericqUpdateGeneralFurther recovery progress

The misalignment wasn't as bad as I had intially feared; the spot was indeed pretty high on ETMX at first. Both transmon QPDs did need a reasonable amount of steering to center once the dither had centered the beam spots on the optics.

Arms, PRMI and DRMI have all been locked and dither aligned. All oplevs and transmon QPDs have been centered. All AS and REFL photodiodes have been centered. 

Green TM00 modes are seen in each arm; I'll do ALS recovery tomorrow. 

  11414   Tue Jul 14 17:14:23 2015 EveSummarySummary PagesFuture summary pages improvements

Here is a list of suggested improvements to the summary pages. Let me know if there's something you'd like for me to add to this list!

  • A lot of plots are missing axis labels and titles, and I often don't know what to call these labels. I could use some help with this.
  • Check the weather and vacuum tabs to make sure that we're getting the expected output. Set the axis labels accordingly. 
  • Investigate past periods of missing data on DataViewer to see if the problem was with the data requisition process, the summary page production process, or something else.
  • Based on trends in data over the past three months, set axis ranges accordingly to encapsulate the full data range.
  • Create a CDS tab to store statistics of our digital systems. We will use the CDS signals to determine when the digital system is running and when the minute trend is missing. This will allow us to exclude irrelevant parts of the data.
  • Provide duty ratio statistics for the IMC.
  • Set triggers for certain plots. For example, for channels C1:LSC-XARM OUT DQ and page 4 LIGO-T1500123–v1 C1:LSC-YARM OUT DQ to be plotted in the Arm LSC Control signals figures, C1:LSCTRX OUT DQ and C1:LSC-TRY OUT DQ must be higher than 0.5, thus acting as triggers.
  • Include some flag or other marking indicating when data is not being represented at a certain time for specific plots.
  • Maybe include some cool features like interactive plots.
  11437   Wed Jul 22 22:06:42 2015 EveSummarySummary PagesFuture summary pages improvements

- CDS Tab

We want to monitor the status of the digital control system.

1st plot
Title: EPICS DAQ Status
I wonder we can plot the binary numbers as statuses of the data acquisition for the realtime codes.
We want to use the status indicators. Like this:
https://ldas-jobs.ligo-wa.caltech.edu/~detchar/summary/day/20150722/plots/H1-MULTI_A8CE50_SEGMENTS-1121558417-86400.png

channels:
C1:DAQ-DC0_C1X04_STATUS
C1:DAQ-DC0_C1LSC_STATUS
C1:DAQ-DC0_C1ASS_STATUS
C1:DAQ-DC0_C1OAF_STATUS
C1:DAQ-DC0_C1CAL_STATUS

C1:DAQ-DC0_C1X02_STATUS
C1:DAQ-DC0_C1SUS_STATUS
C1:DAQ-DC0_C1MCS_STATUS
C1:DAQ-DC0_C1RFM_STATUS
C1:DAQ-DC0_C1PEM_STATUS

C1:DAQ-DC0_C1X03_STATUS
C1:DAQ-DC0_C1IOO_STATUS
C1:DAQ-DC0_C1ALS_STATUS

C1:DAQ-DC0_C1X01_STATUS
C1:DAQ-DC0_C1SCX_STATUS
C1:DAQ-DC0_C1ASX_STATUS

C1:DAQ-DC0_C1X05_STATUS
C1:DAQ-DC0_C1SCY_STATUS
C1:DAQ-DC0_C1TST_STATUS

1st plot
Title: IOP Fast Channel DAQ Status
These have two bits each. How can we handle it?
If we need to shrink it to a single bit take "AND" of them.
C1:FEC-40_FB_NET_STATUS (legend: c1x04, if a legend placable)
C1:FEC-20_FB_NET_STATUS (legend: c1x02)
C1:FEC-33_FB_NET_STATUS (legend: c1x03)
C1:FEC-19_FB_NET_STATUS (legend: c1x01)
C1:FEC-46_FB_NET_STATUS (legend: c1x05)

3rd plot
Title C1LSC CPU Meters
channels:
C1:FEC-40_CPU_METER (legend: c1x04)
C1:FEC-42_CPU_METER (legend: c1lsc)
C1:FEC-48_CPU_METER (legend: c1ass)
C1:FEC-22_CPU_METER (legend: c1oaf)
C1:FEC-50_CPU_METER (legend: c1cal)
The range is from 0 to 75 except for c1oaf that could go to 500.
Can we plot c1oaf with the value being devided by 8? (Then the legend should be c1oaf /8)

4th plot
Title C1SUS CPU Meters
channels:
C1:FEC-20_CPU_METER (legend: c1x02)
C1:FEC-21_CPU_METER (legend: c1sus)
C1:FEC-36_CPU_METER (legend: c1mcs)
C1:FEC-38_CPU_METER (legend: c1rfm)
C1:FEC-39_CPU_METER (legend: c1pem)
The range is be from 0 to 75 except for c1pem that could go to 500.
Can we plot c1pem with the value being devided by 8? (Then the legend should be c1pem /8)

5th plot
Title C1IOO CPU Meters
channels:
C1:FEC-33_CPU_METER (legend: c1x03)
C1:FEC-34_CPU_METER (legend: c1ioo)
C1:FEC-28_CPU_METER (legend: c1als)
The range is be from 0 to 75.

6th plot
Title C1ISCEX CPU Meters
channels:
C1:FEC-19_CPU_METER (legend: c1x01)
C1:FEC-45_CPU_METER (legend: c1scx)
C1:FEC-44_CPU_METER (legend: c1asx)
The range is be from 0 to 75.

7th plot
Title C1ISCEY CPU Meters
channels:
C1:FEC-46_CPU_METER (legend: c1x05)
C1:FEC-47_CPU_METER (legend: c1scy)
C1:FEC-91_CPU_METER (legend: c1tst)
The range is be from 0 to 75.

=====================

IOO

We want a duty ratio plot for the IMC. C1:IOO-MC_TRANS_SUM >1e4 is the good period.

Duty ratio plot looks like the right plot of the following link
https://ldas-jobs.ligo-wa.caltech.edu/~detchar/summary/day/20150722/lock/segments/

=====================

SUS: OPLEV

OL_PIT_INMON and OL_YAW_INMON are good for the slow drift monitor.
But their sampling rate is too slow for the PSDs.
Can you use
C1:SUS-ETM_OPLEV_PERROR
C1:SUS-ETM_OPLEV_YERROR
etc...
For the PSDs? They are 2kHz sampling DQ channels. You would be able to plot
it up to ~1kHz. In fact, we want to monitor the PSD from 100mHz to 1kHz.
How can you set up the resolution (=FFT length)?

=====================

LSC / ASC / ALS tabs

Let's make new tabs LSC, ASC, and ALS

LSC:

We should have a plot for
C1:LSC-TRX_OUT_DQ
C1:LSC-TRY_OUT_DQ
C1:LSC-POPDC_OUT_DQ
It's OK to use the minute trend for now.
You can check the range using dataviewer.

ASC:

Let's use
C1:SUS_MC1_ASCPIT_OUT16 (legend: IMC WFS)
C1:ASS-XARM_ITM_YAW_OSC_CLKGAIN (legend: XARM ASS)
C1:ASS-YARM_ITM_YAW_OSC_CLKGAIN (legend: YARM ASS)
C1:ASX-XARM_M1_PIT_OSC_CLKGAIN (legend: XARM Green ASS)
as the status indicators. There is no YARM Green ASS yet.

ALS:

Title: ALS Green transmission
We want a time series of
ALS-TRX_OUT16
ALS-TRY_OUT16

Title: ALS Green beatnote
Another time series
ALS-BEATX_FINE_Q_MON
ALS-BEATY_FINE_Q_MON

Title: Frequency monitor
We have frequency counter outputs, but I have to talk to Eric to know the channel names

  8045   Fri Feb 8 21:14:52 2013 ManasaUpdateOpticsG&H - AR Reflectivity

 Hours of struggle and still no data 

I tried to measure the AR reflectivity and the loss due to flipping of G&H mirrors

 With almost no wedge angle, separating the AR reflected beam from the HR reflected beam seems to need more tricks.

pr2.png

The separation between the 2 reflected rays is expected 0.8mm. After using a lens along the incident beam, this distance was still not enough to be separable by an iris.

The first trick: I could find a prism and tried to refract the beams at the edge of the prism...but the edges weren't that sharp to separate the beams (Infact I thought an axicon would do the job better..but I think we don't have any of those).

Next from the bag of tricks: I installed a camera to see if the spots can actually be resolved.

The camera image shows the 2 sets of focal spots; bright set to the left corresponding to HR reflected beam and the other from the AR surface. I expect the ghost images to arise from the 15 arcsec wedge of the mirror. I tried to mask one of the sets using a razor blade to see if I can separate them and get some data using a PD. But, it so turns out that even the blade edge is not sharp enough to separate them.

If there are any more intelligent ideas...go ahead and suggest! 

 

27_1044419003.bmp

  8046   Fri Feb 8 22:49:31 2013 KojiUpdateOpticsG&H - AR Reflectivity

How about to measure the AR reflectivity at larger (but small) angles the extrapolate the function to smaller angle,
or estimate an upper limit?

The spot separation is

D = 2 d Tan(\phi) Cos(\theta), where \phi = ArcSin(Sin(\theta) * n)

D = 2 d Tan(\phi) Cos(\theta), where \phi = ArcSin(Sin(\theta) / n)         (<== correction by Manasa's entry)

\theta is the angle of incidence. For a small \theta, D is propotional to \theta.

So If you double the incident angle, the beam separation will be doubled,
while the reflectivity is an even function of the incident angle (i.e. the lowest order is quadratic).

I am not sure until how much larger angle you can use the quadratic function rather than a quartic function.
But thinking about the difficulty you have, it might be worth to try.

  8047   Fri Feb 8 23:04:40 2013 ManasaUpdateOpticsG&H - AR Reflectivity

Quote:

D = 2 d Tan(\phi) Cos(\theta), where \phi = ArcSin(Sin(\theta) * n)

\theta is the angle of incidence. For a small \theta, D is propotional to \theta.

n1Sin(\theta1) = n2 Sin(\theta2)

So it should be

\phi = ArcSin(Sin(\theta) / n 

I did check the reflected images for larger angles of incidence, about 20 deg and visibly (on the IR card) I did not see much change in the separation. But I will check it with the camera again to confirm on that.

  8051   Sat Feb 9 19:34:34 2013 ranaUpdateOpticsG&H - AR Reflectivity

 

 Use the trick I suggested:

Focus the beam so that the beam size at the detector is smaller than the beam separation. Use math to calculate the beam size and choose the lens size and position. You should be able to achieve a waist size of < 0.1 mm for the reflected beam.

  8063   Mon Feb 11 19:55:47 2013 ManasaUpdateOpticsG&H - AR Reflectivity

 

I adjusted the focal length of the focusing lens and reduced the beam size enough to mask with the razor blade edge while looking at the camera and then making measurements using PD.

I am still not satisfied with this data because the R of the HR surface measured after flipping seems totally unbelievable (at around 0.45).

G&H AR reflectivity

R percentage

11 ppm @4 deg
19.8 ppm @6 deg
20 ppm @ 8 deg
30 ppm @ 20 deg

  8075   Wed Feb 13 09:28:56 2013 SteveUpdateOpticsG&H - HR plots

 

 Gooch & Housego optics order specification from 03-13-2010

Side 1: HR Reflectivity >99.99 % at 1064 nm for 0-45 degrees for S & P polarization

Side 2: AR coat R <0.15

The HR coating scans uploaded to 40mwiki / Aux optics today

  8018   Wed Feb 6 20:19:52 2013 ManasaUpdateOpticsG&H and LaserOptik mirrors

[Koji, Manasa]

We measured the wedge angle of the G&H and LaserOptik mirrors at the OMC lab using an autocollimator and rotation stage.

The wedge angles:

G&H : 18 arc seconds (rough measurement)

LaserOptik : 1.887 deg

  12102   Mon May 2 17:06:58 2016 ranaSummaryCOCG&H optics to Fullerton/HWS for anneal testing

Steve sent 4 of our 1" diameter G&H HR mirrors to Josh Smith at Fullerton for scatter testing. Attached photo is our total stock before sending.

Attachment 1: 20160427_182305.jpg
20160427_182305.jpg
  530   Wed Jun 11 15:30:55 2008 josephbConfigurationCamerasGC1280
The trial use GC1280 has arrived. This is a higher resolution CMOS camera (similar to the GC750). Other than higher resolution, it has a piece of glass covering and protecting the sensor as opposed to a plastic piece as used in the GC750. This may explain the reduced sensitivity to 1064nm light that the camera seems to exhibit. For example, the image averages presented here required a 60,000 microsecond exposure time, compared to 1000-3000 microseconds for similar images from the GC750. This is an inexact comparison, and the actual sensitivity difference will be determined once we have identical beams on both cameras.

The attached pdfs (same image, different angles of view) are from 200 averaged images looking at 1064nm laser light scattering from a piece of paper. The important thing to note is there doesn't seem to be any definite structure, as was seen in the GC750 scatter images.

One possibility is that too much power is reaching the CMOS detector, penetrating, and then reflecting back to the back side of the detector. Lower power and higher exposure times may avoid this problem, and the glass of the GC1280 is simply cutting down on the amount passing through.

This theory will be tested either this evening or tomorrow morning, by reducing the power on the GC750 to the point at which it needs to be exposed for 60,000 microseconds to get a decent image.

The other possibility is that the GC750 was damaged at some point by too much incident power, although its unclear what kind of failure mode would generate the images we have seen recently from the GC750.
Attachment 1: GC1280_60000E_scatter_2d.pdf
GC1280_60000E_scatter_2d.pdf
Attachment 2: GC1280_60000E_scatter_3d.pdf
GC1280_60000E_scatter_3d.pdf
  649   Tue Jul 8 21:46:38 2008 YoichiConfigurationPSLGC650M moved to the PMC transmission
I moved a GC650M, which was monitoring the light coming out of the PSL, to the transmission port of the PMC to see the transmitted mode shape.
It will stay there unless someone find other use of it.

Just FYI, you can see the picture from the control computers by the following procedure:

ssh -X mafalda
cd /cvs/cds/caltech/target/Prosilica/40mCode
./SampleViewer

Chose 02-2210A-06223 and click on the Live View icon.
  521   Thu Jun 5 13:35:23 2008 josephbConfigurationCamerasGC750 looking at 1064nm scattered light
I've taken 200 images of the GC750 (CMOS) camera while holding it by hand up to a beam card (also held by hand) in the path of ~5mW of beam power. I then averaged the images to produce the fourth attached plot.

Rob has pointed out the image looks a lot like PCB traces. So perhaps we're seeing the electronics behind the CMOS sensor?

I repeated the same experiment with HeNe laser light (again scattered off a card). These show none of the detailed structure (just what looks to be a large reflection from the card moving around depending on how steady my hand was). These are the first 3 attached plots. So only 1064nm light so far sees these features.

As a possible solution, I did a quick and dirty calibration by dividing a previous PSL output beam by the 1064 average scatter light values. These produce the last attached pdf (with multiple images). The original uncalibrated image is on top, while the very simply calibrated image is on the bottom of each plot.

It seems as the effect may be power dependent (which could still be calibrated properly, but would take a bit more effort than simply dividing), as determined by looking at the edges of the calibrated plot.
Attachment 1: GC750_HeNe_scatter_avg.pdf
GC750_HeNe_scatter_avg.pdf
Attachment 2: GC750_HeNe_scatter_avg2.pdf
GC750_HeNe_scatter_avg2.pdf
Attachment 3: GC750_HeNe_scatter_avg3.pdf
GC750_HeNe_scatter_avg3.pdf
Attachment 4: GC750_scatter_avg.pdf
GC750_scatter_avg.pdf
Attachment 5: GC750_nitrogen_white.pdf
GC750_nitrogen_white.pdf GC750_nitrogen_white.pdf GC750_nitrogen_white.pdf GC750_nitrogen_white.pdf GC750_nitrogen_white.pdf GC750_nitrogen_white.pdf GC750_nitrogen_white.pdf
  378   Fri Mar 14 12:06:29 2008 josephbConfigurationCamerasGC750 looking at ETMX while locked
The GC750 (CMOS) is currently looking at the front of ETMX. Unfortunately, its being routed through a 10Mbit connection (which I will be purchasing a replacement for today), so getting it to send images to Mafalda/Linux 2 or 3 isn't working well, but by using a local gigabit switch and a laptop I can get sufficient speed for full images with the sample viewer.

The attached image is from a full 752x480 reslution with 10,000 microsecond exposure with the X-arm locked. Although it looks like I still need to work on the focusing. Will be switching the GC750 with the GC 650 (CCD) later today and comparing the resulting images.
Attachment 1: ETMX_zoom_exp_10000_750.tiff
  558   Tue Jun 24 17:12:10 2008 josephb, EricConfigurationCamerasGC750 setup, 1X4 Hub connected, ETMX images
The GC750 camera has been setup to look at ETMX. In addition, the new 1X4 rack mounted switch (131.215.113.200) has been connected via new cat6 cable to the control room hub (131.215.113.1?), thanks to Eric. The camera is now plugged into 1X4 rack switch and now has a gigabit connection to the control room computers as well as Mafalda (131.215.113.23).

By using ssh -X mafalda or ssh -X 131.215.113.23, then typing:

target
cd Prosilica/bin-pc/x86/
./Sampleviewer

A viewer will be brought up. By clicking on the 3rd icon from the left (looks like an eye) will bring up a live view.

Closing the view, and then cd ../../40mCode, and then running ./Snap --help will tell you how to use a simple code for taking .tiff images as well as setting things such as exposure length and size of image (in pixels) to send.

When the interferometer was set to an X-arm only configuration, we took two series of 200 images each, with two different exposure lengths.

Attached are three pdf images. The first is just a black and white single image, the second is an average of 100 images, and the third is the standard deviation of the 100 images.
Attachment 1: GC750_ETMX_E30000_single.pdf
GC750_ETMX_E30000_single.pdf
Attachment 2: GC750_ETMX_E30000_avg.pdf
GC750_ETMX_E30000_avg.pdf
Attachment 3: GC750_ETMX_E30000_std.pdf
GC750_ETMX_E30000_std.pdf
  10854   Mon Jan 5 20:17:26 2015 jamieConfigurationCDSGDS upgraded to 2.16.14

I upgraded the GDS and ROOT installations in /ligo/apps/ubuntu12 the control room workstations:

  • GDS 2.16.14
  • ROOT 5.34.18 (dependency of GDS)

My cursory tests indicate that they seem to be working:

2015-01-05-200025_1694x996_scrot.png

Now that the control room environment has become somewhat uniform at Ubuntu 12, I modified the /ligo/cdscfg/workstationrc.sh file to source the ubuntu12 configuration:

controls@nodus|apps > cat /ligo/cdscfg/workstationrc.sh
# CDS WORKSTATION ENVIRONMENT
source /ligo/apps/ligoapps-user-env.sh
source /ligo/apps/ubuntu12/ligoapps-user-env.sh
source /opt/rtcds/rtcds-user-env.sh
controls@nodus|apps > 

This should make all the newer versions available everywhere on login.

  7238   Tue Aug 21 00:02:05 2012 ranaSummaryComputer Scripts / ProgramsGDS/DTT bug: 10 digit GPS times not accepted

 I've noticed that we're experiencing this bug which was previously seen at LHO. We cannot enter 10 digit GPS times into the time fields for DTT due to a limit in TLGEntry.cc, which Jim Batch fixed in September of last year. Seems like we're running an old version of the GDS tools.

I checked the Lidax tool (which you can get from the GDS Mainmenu). It does, in fact, allow 10 digit entries.

  13   Thu Oct 25 00:01:21 2007 ranaSoftware InstallationCDSGEO DV => LIGO DV
Martin Hewitson of GEO600 fame has modified the cool GEO DV
to work with the LIGO NDS system with some NDS advice from Rolf (who's over in Germany this week).

I've moved it onto the 40m CDS system and installed it on the AdhikariLab computer named 'django'. It worked immediately.

I modified the main .m file to include the 40m's NDS server. When you run it you have to include the path to the NDS
client written by Ben Johnson.

The attached is a screenshot of it working on a Mac; it looks as cool on Linux.

Its installed in /cvs/cds/caltech/apps/ligoDV/. In matlab you navigate to that directory and then
type addpath('/cvs/cds/caltech/apps/linux/UNIX_NDS_Client_beta2/') to add the NDS client.
On the Solaris machines, type type addpath('/cvs/cds/caltech/apps/solaris9/UNIX_NDS_Client_beta2/') instead.

Then type ligoDV to start it up. Then click away and have fun.

In the example I've selected
C1:PEM-BS_ACC_EAST_Z
and plotted its specgram.

Big grin
Attachment 1: Picture_1.png
Picture_1.png
  144   Fri Nov 30 11:22:22 2007 ajwSummaryCDSGEO DV => LIGO DV

Quote:
Martin Hewitson of GEO600 fame has modified the cool GEO DV
to work with the LIGO NDS system with some NDS advice from Rolf (who's over in Germany this week).

I've moved it onto the 40m CDS system and installed it on the AdhikariLab computer named 'django'. It worked immediately.

I modified the main .m file to include the 40m's NDS server. When you run it you have to include the path to the NDS
client written by Ben Johnson.

The attached is a screenshot of it working on a Mac; it looks as cool on Linux.

Its installed in /cvs/cds/caltech/apps/ligoDV/. In matlab you navigate to that directory and then
type addpath('/cvs/cds/caltech/apps/linux/UNIX_NDS_Client_beta2/') to add the NDS client.
On the Solaris machines, type type addpath('/cvs/cds/caltech/apps/solaris9/UNIX_NDS_Client_beta2/') instead.

Then type ligoDV to start it up. Then click away and have fun.

In the example I've selected
C1:PEM-BS_ACC_EAST_Z
and plotted its specgram.

Big grin


Download and installation instructions, as well as a few examples for use
can be found here (typical lsc username and password):

https://www.gravity.phy.syr.edu/dokuwiki/doku.php?id=ligodv:home
https://www.gravity.phy.syr.edu/dokuwiki/doku.php?id=ligodv:downloading_the_ligodv_software
  234   Thu Jan 10 13:45:52 2008 PkpUpdateCamerasGLIBC Error
So, I have tried to compile the camera files which are in /cvs/cds/caltech/target/Prosilica/examples for the past 2 days now and have been unable to get rid of the following error. (specifically ListCameras.cpp, as it doesnt have any other libraries required, which unnecessarily complicates things)

../../bin-pc/x86/libPvAPI.so: undefined reference to `__stack_chk_fail@GLIBC_2.4'
collect2: ld returned 1 exit status
make: *** [sample] Error 1

I used to get this error on mafalda too, but I had fixed it by installing the latest version of the glibc libraries. Inspite of doing so on linux2, the error still persists. I suspect it had something to do with it being a FC3 machine. My own laptop, which also runs Ubuntu works fine too. The problem with these Ubuntu machines is that they dont let me set the packet sizes to 9 kb which is required by the camera. Linux2 does.

If anyone has any idea how to resolve this issue, please let me know.

Thanks
Pinkesh.
  158   Mon Dec 3 16:24:47 2007 tobinHowToComputersGNU screen
GNU screen is a utility that can be quite handy for managing long-running psuedo-interactive terminal programs on remote machines. In particular, I think it might be useful in developing and testing "Matlab DMT" tools on Mafalda.
  142   Thu Nov 29 18:10:13 2007 AlbertoHowToComputer Scripts / ProgramsGPIB Scripts
I've spent a lot of time trying to configurate the GPIB-USB interface for the HP4195. After installing 1) the Agilent libraries, 2) the drivers, 3) the matlab Instrument Toolbox, 4) Jamie script, 5) Alice's script the computer can see the HP but still they can't 'talk' to each other.
I give up. I asked Alice Wang how she managed to get data. I'm not sure she used the GPIB interace. Rob said she might have used the old fashion floppy disks that we can't read anymore here.
I would really appreciate any suggestion by anyone who happened to have the same problems.
  143   Thu Nov 29 19:35:14 2007 ranaHowToComputer Scripts / ProgramsGPIB Scripts

Quote:
I've spent a lot of time trying to configurate the GPIB-USB interface for the HP4195. After installing 1) the Agilent libraries, 2) the drivers, 3) the matlab Instrument Toolbox, 4) Jamie script, 5) Alice's script the computer can see the HP but still they can't 'talk' to each other.
I give up. I asked Alice Wang how she managed to get data. I'm not sure she used the GPIB interace. Rob said she might have used the old fashion floppy disks that we can't read anymore here.
I would really appreciate any suggestion by anyone who happened to have the same problems.


Alice and Jamie used the USB-GPIB interface. You should just try using the black laptop which already has this capability or ask Jamie Rollins
who actually knows something.
  3969   Mon Nov 22 20:01:56 2010 kiwamuConfigurationComputersGPIB box : took it out from HP3563A and connect it to AG4395A

 I disconnected the yellow GPIB box from the backside of HP3563A (classic analyzer),

and connected it to AG4395A (network analyzer), which is the official place for it.

  3120   Fri Jun 25 12:09:27 2010 kiwamuUpdateComputersGPIB controller of HP8591E

I've just stolen a GPIB controller, an yellow small box, from the spectrum analyzer HP8591E.

The controller is going to be used for driving the old spectrum analyzer HP3563A for a while.

Gopal and I will be developing and testing a GPIB program code for HP3563A via the controller.

Once after we get a new GPIB controller, it will be back to the original place, i.e. HP8591E.

 

--- GPIB controller ----

name: teofila

address: 131.215.113.106

  1479   Mon Apr 13 18:57:03 2009 AlbertoFrogsComputersGPIB/ETH Interface Troubles

I really don't understand why my programs that I used to use to get data from the HP Spectrum Analyzer and the Marconi frequency generator don't work anymore.

I spent hours trying to debug the code but I can't sort the problem out.

The main problem seem to be with the function recv from the socket library. Somehow it can't anymore get any data from the instruments. The thing I can't understand, though, is that if called directly from the python terminal it works fine!

In particular the problem is with the following lines in my code:

netSock.send("mkpk;mka?\n")
netSock.send("++read eoi\n")
tmp = netSock.recv(1024)

Tried a lot of tickering but it didn't work.

I attach the two scripts I've been using. One (sweepfrequencyPRC.py) calls the other (HP4395PRC.py).

They worked egregiously for weeks in the past. Don't know what happened since then.

Attachment 1: sweepfrequencyPRC.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
... 53 more lines ...
Attachment 2: HP8590PRC.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 *
... 70 more lines ...
  1481   Tue Apr 14 12:10:11 2009 AlbertoFrogsComputersGPIB/ETH Interface Troubles

Quote:

I really don't understand why my programs that I used to use to get data from the HP Spectrum Analyzer and the Marconi frequency generator don't work anymore.

I spent hours trying to debug the code but I can't sort the problem out.

The main problem seem to be with the function recv from the socket library. Somehow it can't anymore get any data from the instruments. The thing I can't understand, though, is that if called directly from the python terminal it works fine!

In particular the problem is with the following lines in my code:

netSock.send("mkpk;mka?\n")
netSock.send("++read eoi\n")
tmp = netSock.recv(1024)

Tried a lot of tickering but it didn't work.

I attach the two scripts I've been using. One (sweepfrequencyPRC.py) calls the other (HP4395PRC.py).

They worked egregiously for weeks in the past. Don't know what happened since then.

This morning Joe looked at my code and made me notice that for some reason the query to the Spectrum Analyzer made by netSock.recv(1024) contained two answers. It was like the buffer contained the answer two different queries.

After some experiment I found that basically the GPIB interface wasn't switching from the "auto 1" to the "auto 0" mode as it should. I rewrote part of the code and that seemed have solved the problem.

Still don't understand why it used to work in the past and then it stopped.

  5994   Thu Nov 24 02:23:43 2011 KojiSummaryGeneralGPIB<->WIFI

GPIB<->WIFI on Agilent Network Analyzer 4395A was broken.
The connection was fixed by replacing and configuring the LINKSYS bridge.

=======

Kiwamu and I have identified that the LINKSYS bridge was guilty.

I knew that we had another one in the bathroom, I configured it.

HOW TO CONFIGURE IT

  • You need a host with 192.168.1.*.
  • Connect the host and the LINKSYS directly
  • Open http://192.168.1.226/
  • Select 40MARS and infrastructure mode
  • Register it in the MAC filter of the 40MARS (see wiki and use your head)

The new unit works fine.

I checked the malfunctioning unit and the configuration was the same as the others.

The bad one detected the existence of 40MARS during the configuration, but it does not establish
the connection in the actual use. I am afraid that something is broken or some setting is lost
during the power supply shutdown.

  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.
  1133   Thu Nov 13 15:50:44 2008 AlbertoConfigurationGeneralGPS 10MHz clock
The schematic of the 1Y7 rack that Alan pointed out (see attachment) don't represent anymore the actual rack.
First, with Yoichi we found that the GPS receiver for the 10 MHz is in a different position,
on the other side of the VME computer. It seems to output 1 kHz, which also appears in some modulated way.
This signal is then passed to a board on 1Y7 that seems make just copies of the signal. One of these goes
to an other board in 1Y6 that looks like a GPS receiver but has actually no GPs antenna input. Here it is
not connected to anything, but on its same crate is a the awg computer, so it might be providing the clock
to that by the crate.

We also checked the clock monitor output on the boards in the PSL that provides for the clock to the Penteks
and it seems that these are actually getting 4MHz.
Attachment 1: rackstuff.pdf
rackstuff.pdf rackstuff.pdf rackstuff.pdf rackstuff.pdf
  12182   Wed Jun 15 10:19:10 2016 SteveConfigurationCDSGPS antennas... debugging

Visual inspection of rooftop GPS antennae:

The 2 GPS antennas are located on the north west corner of CES roof. Their condition looks well weathered. I'd be surprised if they work.

The BNC connector of the 1553 head is inside of the conduit so it is more likely to have a better connection than the other one.

I have not had a chance to look into the "GPS Time Server" unit.

Attachment 1: GPStimeServer.jpg
GPStimeServer.jpg
Attachment 2: GPSsn.jpg
GPSsn.jpg
Attachment 3: GPSantennas.jpg
GPSantennas.jpg
Attachment 4: GPSantHead.jpg
GPSantHead.jpg
Attachment 5: GPSantHead2.jpg
GPSantHead2.jpg
Attachment 6: GPSantCabels.jpg
GPSantCabels.jpg
  13211   Tue Aug 15 16:32:42 2017 Jamie, GautumUpdateCDSGPS receiver apparently set to correct mode as "UTC"
Quote:

The setting when we found it was "GPS", which seems logical enough.  However, when we switched it to "UTC" the time as shown on the front panel was correct, now with "UTC" vertically to the right of the time, and fb1 was then showing the correct GPS time.

From Keith Thorne:

In the GPS receiver, you are trying to match the IRIG-B output format that is created by the aLIGO IRIG-B Fanout.  Since we have to prep the aLIGO IRIG-B Fanout every time there is a leap second coming, I would suspect that we are sending UTC to the IRIG-B receivers.  Thus, the GPS receiver needs to be set to that mode.

Soooo, "UTC" is the correct mode for the GPS receiver.

  12167   Fri Jun 10 12:21:54 2016 jamieConfigurationCDSGPS receiver not resetting properly

The GPS receiver (EndRun Technologies box in 1Y5? (rack closest to door)) seems to not coming back up properly after the reboot.  The front pannel says that it's "LKD", but the "sync" LED is flashing instead of solid, and the time of year displayed on the front panel is showing day 6.  The fb1 symmetricom driver and VME timing module are still both seeing day 299, though.  So something may definitely be screwy with the GPS receiver.

  12200   Mon Jun 20 11:11:20 2016 SteveConfigurationCDSGPS receiver not resetting properly

I called https://www.endruntechnologies.com/pdf/USM3014-0000-000.pdf  and they said it's very likely just needs a software update. They will email Jamie the details.

Quote:

The GPS receiver (EndRun Technologies box in 1Y5? (rack closest to door)) seems to not coming back up properly after the reboot.  The front pannel says that it's "LKD", but the "sync" LED is flashing instead of solid, and the time of year displayed on the front panel is showing day 6.  The fb1 symmetricom driver and VME timing module are still both seeing day 299, though.  So something may definitely be screwy with the GPS receiver.

 

ELOG V3.1.3-