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ID Date Authorup Type Category Subject
  13444   Wed Nov 22 05:41:32 2017 ranaUpdateOptical LeversOplev "noise budget"

For the OL NB, probably don't have to fudge any seismic noise, since that's a thing we want to suppress. More important is "what the noise would be if the suspended mirrors were no moving w.r.t. inertial space".

For that, we need to look at the data from the OL test setup that Steve is putting on the SP table.

  13451   Wed Nov 22 19:20:01 2017 ranaUpdateOptical LeversOplev "noise budget"

too complex; just shoot straight from the HeNe to the QPD. We lower the gain of the QPD by changing the resistors; there's no sane reason to keep the existing 100k resistors for a 2 mW beam. The specular reflection of the QPD must be dumped on a black glass V dump (not some flimsy anodized aluminum or dirty razor stack)

  13455   Tue Nov 28 16:02:32 2017 ranaUpdatePEMseismometer can testing

I've ordered 4 of these from McMaster. Should be delivered to the 40m by noon tomorrow.


For the insulation, I have decided to use this one (Buna-N/PVC Foam Insulation Sheets). We will need 3 of the 1 inch plain backing ones (9349K4) to wrap a few layers around it. I'll try two layers for now, since the insulation seems to be doing quite well according to initial testing.

Kira and I also discussed the issiue. It would be good if someone can hunt aroun on the web and get some free samples of non-shedding foam with R~4.

  13457   Wed Nov 29 15:33:16 2017 ranaUpdatePSLPMC locking

PMC wasn't locking. Had to power down c1psl. Did burt restore. Still not great.

I think many of the readbacks on the PMC MEDM screen are now bogus and misleading since the PMC RF upgrade that Gautam did awhile ago. We ought to fix the screen and clearly label which readbacks and actuators are no longer valid.

Also, the locking procedure is not so nice. The output V adjust doesn't work anymore with BLANK enabled. Would be good to make an autolocker script if we find a visitor wanting to do something fun.

  13474   Thu Dec 14 07:07:09 2017 ranaUpdateIOOLots of red on the FE status screen

I had to key the c1psl crate to get the PMC locking again. Without this, it would still sort of lock, but it was very hard to turn on the loop; it would push itself off the fringe. So probably it was stuck in some state with the gain wrong. Since the RF stuff is now done in a separate electronics chain, I don't think the RF phase can be changed by this. Probably the sliders are just not effective until power cycling.


Once the RT machines were back, we launched only the five IOPs. They had bunch of red lights, but we continued to run essential models for the IFO. SOme of the lights were fixed by "global diag reset" and "mxstream restart".

The suspension were damped. We could restore the IMC lock. The locking became OK and the IMC was aligned. The REFL spot came back.

At least, I could confirm that the WFS ASC signals were not transmitted to c1mcs. There must be some disconneted links of IPC.

I then tried to get the MC WFS back, but running rtcds restart --all would make some of the computers hang. For c1ioo I had to push the reset button on the computer and then did 'rtcds start --all' after it came up. Still missing IPC connections.

I'm going to get in touch with Rolf.

  13483   Fri Dec 15 18:23:03 2017 ranaUpdatePEMTrillium seismometer DC offset

UVW refers to the 3 internal, orthogonal velocity sensors which are not aligned with the vertical or horizontal directions. XYZ refers to the linear combinations of UVW which correspond to north, east, and up.

  13484   Fri Dec 15 18:24:46 2017 ranaSummaryOptical LeversPRM

Today Angelina and I looked at the PRM OL with an eye towards installing a 2nd QPD. We want to try out using 2 QPDs for a single optic to see if theres a way to make a linear combination of them to reduce the sensitivity to jitter of the HeNe laser or acoustic noise on the table.

The power supply for the HeNe was gone, so I took one from the SP table.

There are WAY too many optics in use to get the beam from the HeNe into the vacuum and then back out. What we want is 1 steering mirror after the laser and then 1 steering mirror before the QPD. Even though there are rumors that this is impossible, I checked today and in fact it is very, very possible.

More optics = more noise = bad.

  13487   Mon Dec 18 17:48:09 2017 ranaUpdateComputersrossa: SL7.3 upgrade continues

Following instructions from LLO-CDS fo the rossa upgrade. Last time there were some issues with not being to access the LLO EPEL repos, but this time it seems to be working fine.

After adding font aliases, need to run 'sudo xset fp rehash' to get the new aliases to take hold. Afterwards, am able to use MEDM and sitemap just fine.

But diaggui won't run because of a lib-sasl error. Try 'sudo yum install gds-all'.

diaggui: error while loading shared libraries: libsasl2.so.2: cannot open shared object file: No such file or directorycrying (have contacted LLO CDS admins)

X-windows keeps crashing with SL7 and this big monitor. Followed instructions on the internet to remove the generic 'Nouveau' driver and install the proprietary NVDIA drivers by dropping to run level 3 and runnning some command line hoodoo to modify the X-files. Now I can even put the mouse on the left side of the screen and it doesn't crash. laugh

  13491   Fri Dec 22 09:40:19 2017 ranaSummaryGeneralDAC noise contribution to squeezing noise budget
  1. Should not count the ITMs. On those we can use big resistors / filters to cut out the noise.
  2. For the initial LIGO, we used 7 K resistors and the mass was 10 kg. But...the output driver went +/- 150 V.

So we had a max F/m = (20 mA * 0.064 N/A)/(10 kg) = 0.0001. For the 40m, to get the same thing, we would need 40x less current (~0.5 mA). At the moment we have (12 V / 400 Ohm) = 30 mA.

We need to get a spectrum and times series of the required coil current for acquiring and holding the DRMI, and also the single arm. Then we can see where to make noise reductions to allow this drastic force reduction. 

Coil Driver Upgrade wiki here.

  13494   Sun Dec 31 12:43:50 2017 ranaSummaryElectronicsSR560: reworking

I have ordered some LSK389A (in both the SOIC-8 and TO-71 packages) to replace the SR560's default front end FET pair (NPD5565).

I'm going to rework s# 00619 once these new FETs come in. Also ordered 100 of the SOIC-8 to DIP-8 adapter boards from Digikey.

This plot shows the current performance compared to the Rai Low Noise box. I expect the FETs should let us get to ~1.5 nV/rHz with the SR560.

Attachment 1: Preamps.pdf
  13498   Wed Jan 3 12:33:16 2018 ranaUpdateOptimal ControlOplev loop tuning

When putting code into git.ligo.org, one way to have automated testing is to use the Gitlab CI. This is an automated 'checker', much like the 'Travis' system used in GitHub. Essentially, you give it a make files which it runs somewhere and your GIT repo web page gets a little 'failed/passing' badge telling you if its working. You can also browse the logs to see in detail what happened. This avoids the 'but it works on my computer!' thing that we usually hear.


The current version of the code I am using is here: although I may not have inculded some of the data files required to run it, to be fixed...


  13504   Fri Jan 5 17:50:47 2018 ranaConfigurationComputersmotif on nodus

I had to do 'sudo yum install motif' on nodus so that we could get libXm.so.4 so that we could run MEDM. Works now.

  13505   Fri Jan 5 19:19:25 2018 ranaConfigurationSEIBarry Controls 'air puck' instead of 'VOPO style' breadboard

We've been thinking about putting in a blade spring / wire based aluminum breadboard on top of the ETM & ITM stacks to get an extra factor of 10 in seismic attenuation.

Today Koji and I wondered about whether we could instead put something on the outside of the chambers. We have frozen the STACIS system because it produces a lot of excess noise below 1 Hz while isolating in the 5-50 Hz band.

But there is a small gap between the STACIS and the blue crossbeams that attache to the beams that go into the vacuum to support the stack. One possibility is to put in a small compliant piece in there to gives us some isolation in the 10-30 Hz band where we are using up a lot of the control range. The SLM series mounts from Barry Controls seems to do the trick. Depending on the load, we can get a 3-4 Hz resonant frequency.

Steve, can you please figure out how to measure what the vertical load is on each of the STACIS?

Attachment 1: mm_slm.jpg
Attachment 2: Screen_Shot_2018-01-05_at_7.25.47_PM.png
  13506   Fri Jan 5 21:54:28 2018 ranaUpdateGeneralpower outage - timing error

Rolf came here in the morning, but not sure what he did or if Jamie remotely did something. But the screen is green.

Attachment 1: huh.png
  13509   Sat Jan 6 13:47:32 2018 ranaUpdatePonderSqueezeDisplacement requirements for short-term squeezing
  • ought to tune for 210 Hz (in-between powerlines) since 100 Hz is tough to work due to scattering, etc.
  • rename DAC - I think what this curve shows is really the coil driver noise. The DAC noise we can always filter out with the dewhitening board; i.e. once we have 1000x attenuation between the DAC and the coil driver input, DAC noise is not dominant.
  13516   Mon Jan 8 20:50:01 2018 ranaSummaryElectronicsSR560: reworking

I replaced the NPD5565 with a LSK389 (SOIC-8 with DIP adapter). There was a noise reduction of ~30%, but not nearly as much as I expected. I wonder if I have to change the DC bias current on these to get the low noise operation?


  13528   Wed Jan 10 22:19:44 2018 ranaUpdateSUSETMX DC alignment

Best to just calibrate the ETM OL in the usual way. I bet the OSEM outputs have a cal uncertainty of ~50% since the input matrix changes as a function of the DC alignment. Still, a 30 urad pitch mis-alignment gives a (30e-6 rad)(40 m) ~ 1 mm beam spot shift. This would be enough to flash other modes, but it would still be easy to lock on a TEM00 like this. I also doubt that the OL calibration is valid outside of some region near zero - can easily check by moving the ETM bias sliders.


I should've put in the SUSPIT and SUSYAW channels in the previous screenshot. I re-aligned ETMX till I could see IR flashes in the arm, and also was able to lock the green beam on a TEM00 mode with reasonable transmission. As I suspected, this brought the Oplev spot back near the center of it's QPD. But the answer to the question "How much did I move the ETM by" still varies by ~1 order of magnitude, depending on if you believe the OSEM SUSPIT and SUSYAW signals, or the Oplev error signals - I don't know which, if any, of these, are calibrated.

What we still don't know is if this is due to Johannes/Aaron working at the ETMX rack (bumping some of the flaky coil cables and/or bumping the blue beams which support the stack). Adding or substracting weight from the stack supports will give us an ETM mis alignment.

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

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

  13564   Sat Jan 20 15:57:11 2018 ranaUpdateElectronicsWhitening filter D990694

this is the note from Hartmut Grote on this topic from 2004

  13619   Wed Feb 7 19:14:19 2018 ranaUpdatePEMPID test plan
  1. The heater circuit should get its own dedicated supply.
  2. We do not want to ever use the old Ref Cav heater for anything. Its unreliable and noisy.
  3. Steve should update all the sticky labels on all the power supplies in the lab to indicate what voltage they should be set at. Even if the label is correct, the date should be updated.
  13657   Mon Feb 26 20:55:56 2018 ranaUpdateALSDaughter board prototyping

Looks good.

* for bypass type applications, you don't have to use Wima caps (which are bigger and more expensive). You can just use any old ceramic SMD cap.

* This seems like a classic case to use the 3 op-amp instumention amplifier config. This is similar, but not quite.

* Ought to use output resistors of ~50 Ohms by default in the output of any circuit. SInce this is a daughter board, maybe 10 Ohms is enough, but the eventual PCB should have pads for it.

  13700   Fri Mar 23 12:00:20 2018 ranaUpdatePEMtest setup

we don't ever want to use our 16 kHz real time system for such low frequency action; its main purpose is for real-time controls, whereas we are OK with multiple seconds of delay in a thermal loop. The Python PID script is sufficient and highly reliable (after years of testing).

  13705   Mon Mar 26 21:25:55 2018 ranaSummaryIOOMC2 Trans table has issues

Gautam, Rana

While at the MC2 table, we noticed that it has some optical problems:

  1. There is an ND filter mounted to the beam reducing lens. ND filters are illegal, Steve. It causes too much scattering noise. We should instead have a beamsplitter and a dump.
  2. One of those bad U100-AC28 mounts is in use. This is one of those ones with plastic clips that Osamu liked, but the plastic gets in the way of the beam. Needs to be removed.
  3. Reflections from the QPD and the PDA255 are not dumped. This causes noise. Bad.
  4. The QPD transimpedance should be reduced so that it can handle more light. I don't know what it has now, but its probably 10-100 kOhm.

We estimated that the power in the IMC is (1 W)*Finesse/pi = 500 W. The MC2 Transmission spec is < 10 ppm, so the power on the table is probably ~5 mW. Since the PDA255 has a transimpedance of 10 kOhm and a max output power of 10V, it can handle up to ~1 mW. Probably we can get the QPD to handle 4 mW.

Gautam, Steve  3-27

We measured MC2 transmitted power right at the uncoated window ~2.5 mW  The beam was just a little bigger than the meter.

Attachment 1: 20180326_201929.jpg
  13721   Fri Mar 30 06:14:31 2018 ranaUpdateIOOMCREFL_PD Optical response measurement

the noise eater on/off measurements should be done for 0-100 kHz and from the demod board output monitor

  13722   Fri Mar 30 06:16:45 2018 ranaUpdatePEMPID test

Can't really figure out what this plot means. We need to see the sensor (in units of deg C) and the control signal (in heating power (W)). The plot should show a few step responses with the PID loop on, so that we can see the loop response time. Please zoom in on the axes so that we can see what's happening.


[Kira, Gautam]

We closed the loop today and implemented the PID script. I have attached the StripTool graph for an integral value of 0.5 and proportional value of 20. We had some issues getting it to work properly and it would oscillate between some low values of the control voltage. The set point here was -3.20, which corresponds to about a 20 degree increase in temperature. The next step would be to find which values of Kp, Ki, and Kd would work in this case and low pass filter the signal from the temperature sensor, and also create an MEDM screen for easier PID control.


  13736   Fri Apr 6 18:28:57 2018 ranaUpdatePEMPID tuning

Made some changes:

  1. Set P and D gains to zero. We only need slow drift control.
  2. Changed names of the python script and .ini file to distinguish it from the FSS stuff. Lives in scripts/PEM/
  3. removed debug flag from argParse. To run in non-debug mode you use the "-O" option of python as usual.
  4. Fixed the upper/lower limit convention for the heater. Was backwards.
  5. Removed the "rail" function that was defined. We can just use numpy.clip since that's already built in.

There is also now a StripTool file in the scripts/PEM directory which has appropriate channel names and scales for PID loop tuning. Use this file!

I'm leaving it running over the weekend with K_I = -0.003. There is a StripTool on rossa which you can watch. The code itself is running on a tmux session on megatron. Let's ONLY run this code there until we're satisfied that things are good.

Update Sun Apr 8 00:40:11 2018: Lowered gain by factors of 3 down to -0.0001 Saturday afternoon. Seems like still oscillating a bit, now with a ~4 hour period. Setting it to -3e-5 now. Usually we have a linear feedback loop, but our actuation voltage actually gets squared (P = I^2 R) before being integrated to produce temperature. Wonder if we should think of linearizing the feedback control signal to make the loop act nicer.

Update Sun Apr 8 21:09:48 2018: Set K_I = -1e-5 earlier today. Seems to have stabilized nearly, but temperature swings are still +/- 1 K. Will need to add some proportional feedback (K_P) to increase the loop bandwidth, but system is at least sort of stable now. Probably should start construction of EY,BS systems now.

Attachment 1: HeaterTest.png
  13743   Mon Apr 9 23:49:50 2018 ranaUpdatePSLPSL chans

I think we can scrap the 126MOPA channels since they're associated with the Lightwave NPRO and MOPA. We should add the channels that we need for monitoring the Innolight NPRO from the d-sub connector on its controller.

  13750   Fri Apr 13 00:20:46 2018 ranaUpdatePEMMEDM setup

changed the setpoint of the EX Seismomter T ctrl servo from 35 to 39 C to see if this helps the stability by decreasing the cooldown time constant.

  13760   Wed Apr 18 16:59:35 2018 ranaUpdatePEMfinal setup sketch: EX Seis

Can you please add dimensions to the drawing, so we can see if things fit and what the cable lenghts need to be?

For the panel on the granite slab, we should use a thinner piece of metal and mount it with an offset so that the D-sub cable can be fished through the hole in the slab. The hole is wide enough for 2 cables, but not 2 connectors.

Attached is a 8-day minute trend of the heater control signals, as well as the in-loop temperature sensor (which underestimates the true fluctuations; we really need an out-of-loop sensor attached to the can or seismometer).

You can see that since the last tuning (on the 13th), its been stable at the set point of 39 C with 8.5 - 10 W of heating power. Need to add the PID loop settings (all the sliders on the MEDM screen) to the frames so that we can help in diagnosing. Also, fix the spelling of "Celcisususs".

Attachment 1: Screen_Shot_2018-04-18_at_5.20.53_PM.png
  13761   Wed Apr 18 17:15:35 2018 ranaConfigurationComputersNODUS: no xmgrace for dataviewer

Turns out, there is no RPM for XmGrace on Scientific Linux 7. Since this is the graphic output of dataviewer, we can't use dataviewer through X windows until this gets fixed. CDS is looking into a xmGrace replacement, but it would be better if we can hijack a alt RH repo to steal a temporary xmgrace RPM. KT has been pinged.

  13768   Thu Apr 19 11:29:11 2018 ranaUpdatePEMPID tune

Yesterday, I changed the P gain of the PID loop from zero to  +0.1. Seems good so far; will monitor for a couple days to see if we're in the right ballpark. Main issue in the stability may now be that the quantization noise is too big for the temperature sensor. If so, we should consider subtracting off the DC value (with a V ref) and then amplifying before ADC.

Attachment 1: Screen_Shot_2018-04-19_at_11.27.08_AM.png
  13780   Mon Apr 23 20:06:35 2018 ranaUpdatePEMPID tune

This shows a step response of the EX seis temp control with K_I = -1 and K_P = -0.1. The time constants for both heatup and cooldown are ~2 hours.

I'm not so sure if the PID code itself makes sense though:

  # The basic finite-difference PID approximation
  e[0] = (p-s)
  print("Error signal = {}" .format(e[0])) 

  # These are the main equations of the PID Process
  u[0] = u[1]
  u[0] = u[0] + Kp * (e[0] - e[1])
  u[0] = u[0] + Ki * (e[0])
  u[0] = u[0] + Kd * (e[0] - 2*e[1] + e[2])


Seems like the Proportional term uses the difference (or derivative) of the error signal. This makes it more likely to pick up some high frequency noise; maybe we should low pass this signal somewhat, or at least implement a running average.

Since we still don't have an out of loop sensor or a PSL room temperature monitor or a particle counter in the frames, I've disabled the PID loop to see how much the can temperature varies with no feedback. Please leave it this way for a few days.

Attachment 1: HeaterTest.png
  13793   Thu Apr 26 19:46:26 2018 ranaUpdatePEMPID Quixote

Increased the Integral gain (from -1 to -4) on the EX temperature controller. This didn't work a few weeks ago, but now with the added P gain, it seems stable. Daily temperature swings are now ~3x smaller.

Notes for Kira on what we need to do tomorrow (Friday):

  1. add the MEDM screen EPICS values to the DAQ so that we can plot those trends DONE
  2. add the out-of-loop sensor to the EX can
  3. reboot the AUX-EX so we can pick up the new channels and the fixed spelling of the old channels DONE
  4. Re-install EX seismometer and hook up seismometer channels to PEM DAQ so we can start testing its performance.

For those who are flabbergasted by the way I calibrated the TEMP_MON channel from volts to deg C, here's how:

XMgrace->Data->Transformations->Geometric Transforms...

use the 'scale' and 'translate' fields to change the slope and offset for calibration in the obvious ways

Attachment 1: dv.pdf
  13795   Thu Apr 26 23:00:42 2018 ranaUpdatePEMnew Seis temp chans

After fixing the spelling of the EX temperature readback, I also added all of the MEDM sliders to the C0EDCU.ini file (making sure to add an even number of channels). Restarted FB (after installing telnet on rossa):

telnet fb 8083

> shutdown

preferred method of posting DataViewer images: print as a SVG image (since its vectorized). Then from the command line do:

inkscape steven.svg --export-pdf=vass.pdf

Attachment 1: chans.pdf
  13798   Fri Apr 27 18:42:02 2018 ranaUpdatePEMnew Seis temp chans

for whatever reason, I am unable to get minute or second trends from nodus for any channels (IMC, PEM, etc) since the reboot. has there been some more recent FB failure or is this still a bug since last years FB catastrophe?

  13816   Fri May 4 19:06:28 2018 ranaConfigurationElectronicsAUX-PSL PLL Implementation & Characterization

this doesn't make much sense to me; the phase to frequency conversion (mixer-demod to PZT ) should give us a 1/f loop as Johannes mentioned in the meeting. That doesn't agree with your loop shape.

How about give us some more details of the setup including photos and signal/power levels? And maybe measure the LB1005 TF by itself to find out what's wrong with the loop.

  13833   Fri May 11 13:58:42 2018 ranaUpdateGeneralMore refinement of DARM control signal projection

I think "OLG" trace is not labeled right; it would be good to see the actual OLG in addition to whatever that trace actually is.

Based on the first plot, however, my conclusion is that:

  1. we don't need the passive isolator to reduce the control signal; the control signal is dominated by f < 10 Hz.
  2. we should still look into isolators for the reduction of the f > 50 Hz stuff, just to make the overall DARM sensitivity better. But this does not have to be pneumatic since we no longer need 10 Hz isolation. It can instead be a solid piece of rubber to give us a ~20-30 Hz resonance. That would still give us a factor of 5-10 improvement above 100 Hz.
  3. In this case, we only need a mass estimate of the end chamber contents with an accuracy of ~25%. If we think we have that already, we don't need to keep doing the jacks-strain gauge adventure.
  13836   Sat May 12 10:02:03 2018 ranaUpdateGeneralMore refinement of DARM control signal projection

Good question! I've never calculated what the resonance frequency would be if had an inductive resistor with our cable capacitance (~50 pF/m I guess).

  13869   Sun May 20 17:43:01 2018 ranaUpdateElectronicsHow to choose resistors

Article from EE Times, describing why metal foil (NOT metal film) resistors are really better than wirewound when it comes to everything except high power dissipation.

Need to do some diggin to see if we can find ~1k metal foil resistors which can handle ~1W of heat.

Steve: here it is

  13897   Wed May 30 12:13:13 2018 ranaUpdateComputersNODUS: rsyncd + frames

To get our rsync back to LDAS back up, I followed instructions from Dan Kozak:

  1. mounted /frames from fb1: I modified /etc/fstab
  2. modified /etc/rsyncd.conf to allow access from LDAS
  3. restarted rsync as daemon: 'sudo /usr/bin/rsync --daemon --config=/etc/rsyncd.conf'

Next need to figure out what the SL7 protocol is for running this as a daemon after boot - some kind of init.d thing probably

  13917   Tue Jun 5 20:31:42 2018 ranaUpdateCamerasUpdate on GigE Cameras

Aha! Video is back!

I think it would be good to add a flag whereby the video can be saved to disk in some uncompressed video format (ogg, avi, ?) instead of displayed to a matplotlib window. We could then use the default to just display video, but use the save-to-disk flag to grab a few minutes of video for image processing.


In the meantime, I've impemented a simple Python video feed streamer which does work, and which students can use as a base framework to implement more complicated things (e.g., stream multiple feeds in one window, save a video stream movie or animation).

  13960   Thu Jun 14 00:46:09 2018 ranaUpdateIOOWFS HEAD SW confusion

its painful, but you and I should probably take these out, bypass the switches and use them with fixed gain; the 'Reed Relay' attenuators are not a good part for this app.

The historical problem is that they tend to self oscillate with full gain because they had 2 MAX4106 in series which couple to each other in the bad way --- need to remove one of them and set the gain of the other one to 10.


The unfortunate discovery today was that the attenuator switches on the IMC WFS heads are actually assigned to individual segments, and they are active. That means that we have been running the WFS with an uneven gain setting.


  14023   Tue Jun 26 22:06:33 2018 ranaUpdateComputersrossa: SL7.3 upgrade continues: DTT is back

I used the following commands to get diaggui to run on rossa/SL7:

controls@rossa|lib64> ls -lrt libsasl*
-rwxr-xr-x. 1 root root 121296 Feb 16  2016 libsasl2.so.3.0.0
lrwxrwxrwx. 1 root root     17 Dec 18  2017 libsasl2.so -> libsasl2.so.3.0.0
lrwxrwxrwx. 1 root root     17 Dec 18  2017 libsasl2.so.3 -> libsasl2.so.3.0.0
controls@rossa|lib64> sudo ln -s libsasl2.so.3.0.0 libsasl2.so.2
controls@rossa|lib64> ls -lrt libsasl*
-rwxr-xr-x. 1 root root 121296 Feb 16  2016 libsasl2.so.3.0.0
lrwxrwxrwx. 1 root root     17 Dec 18  2017 libsasl2.so -> libsasl2.so.3.0.0
lrwxrwxrwx. 1 root root     17 Dec 18  2017 libsasl2.so.3 -> libsasl2.so.3.0.0
lrwxrwxrwx. 1 root root     17 Jun 26 22:02 libsasl2.so.2 -> libsasl2.so.3.0.0


Basically, I have set up a symbolic link to point sasl2.so.2 to sasl2.so.3.0.0. I've asked LLO again for some guidance on whether or not to find some backport in a non-standard SL7 repo. IF they reply, we may later replace this link with a regular file.

For the nonce, diaggui runs and is able to show us the spectra. We also got swept sine to work. But the FOTON launched from inside of AWGGUI doesn't inherit the sample frequency of the excitation channel so we can't filter noise injections from awggui yet.

  14025   Wed Jun 27 19:05:20 2018 ranaUpdateComputersrossa: SL7.3 upgrade continues: DTT is back

UNELOGGED: someone has changed Pianosa from Ubuntu/Dumbian into SL7. Might be hackers.

Donatella is now the only Ubuntu machine in the control room. I propose we keep it this way for another month and then go fully SL7 if we find no bugs with Pianosa/Rossa.

  14029   Thu Jun 28 10:28:27 2018 ranaUpdateCDS vacuum pneumatic N2 pressure

we disabled logging the N2 Pressure to a text file, since it was filling up disk space. Now it just sends an email to our 40m mailing list, so we'll all get a warning.

The crontab uses the 'bash' version of output redirection '2>&1', which redirects stdout and stderr, but probably we just want stderr, since stdout contains messages without issues and will just fill up again.

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

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


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

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

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

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

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

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

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

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


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

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

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

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

  14100   Tue Jul 24 06:11:50 2018 ranaUpdateCamerasDeveloping neural networks on simulated video

This looks like good progress. Instead of fixed sines or random noise, you should generate now a time series for the motion which is random noise but with a power spectrum similar to what we see for the ETM pitch motion in lock. You can use inverse FFT to get the time series from the open loop OL spectra (being careful about edge effects).


Aim: To develop a neural network that resolves mirror motion from video.

  14113   Sun Jul 29 20:03:02 2018 ranaUpdatePEMSeismometer temp control

While Shruti is re-building Kira's heater circuit, I looked up how to do one of these (i.e. what does a real EE say about how to build a current source?):

It turns out that there is an Analog Devices application note (AN-968) about this (as there usually is once we get tired of playing around and try to look up the right answer).

I've linked to the note and attached the recommended schematic for high current applications. We'll go ahead as is, but we'll make a PCB according to this App Note for the v3 circuit.


Attachment 1: Screen_Shot_2018-07-29_at_8.00.27_PM.png
  14127   Thu Aug 2 23:09:25 2018 ranaSummaryComputersX Green "Mystery" solved

I'm going to guess that this was me: I was disconnecting some octopus power strip nonsense down there (in particular illuminators and cameras), so I might have turned off the AUX rack by mistake.


I walked down to the X end and found that the entire AUX laser electronics rack isn't getting any power. There was no elog about this.

I couldn't find any free points in the power strip where I think all this stuff was plugged in so I'm going to hold off on resurrecting this until tomorrow when I'll work with Steve.


The X arm green does not stay locked to the cavity - the alignment looks fine, and the green flashes are strong, but the lock does not hold. This shouldn't be directly connected to anything we did today since the Green PDH servo is entirely analog.

  14130   Fri Aug 3 16:27:40 2018 ranaUpdateSUSLow noise bias path idea

Bah! Too complex.

ELOG V3.1.3-