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ID Date Author Type Category Subject
184   Mon Dec 10 13:54:26 2007 robHowToComputer Scripts / ProgramsDon't blame the Matlab compiler

For human error. We should be careful to only run the compiler outside the mDV directory (thus placing the _mcr outside of the range the addpath command in the mdv_config files). Or maybe there's a smarter solution...
183   Fri Dec 7 19:14:30 2007 tobinUpdatePSLISS dark noise - ground loop enlightenment
My alleged 60 Hz harmonics were all from a ground loop created by connecting the SR785 ground to the ISS circuit ground; they disappeared when I set the SR785 input to "floating ground." doh!

I modified the ISS PD's to have a 100 ohm resistor in series with the output (in place of 20 ohms). The diodes are again in place on the table, ready for action.
182   Fri Dec 7 18:31:30 2007 tobinUpdateComputer Scripts / Programscompiled matlab hoses itself
Addendnum. The reason the linemon_mcr command was in the path was because of the user issuing the command "addpath(genpath(pwd))" where genpath(D) "returns a path string starting in D, plus, recursively, all the subdirectories of D."

The Matlab compiler is still bad, however.
181   Fri Dec 7 18:28:30 2007 tobinUpdateComputer Scripts / Programscompiled matlab hoses itself
Andrey pointed out to me that some matlab functions in the Signal Processing Toolbox were dying with errors. Looking into the .m file (identified using the "which" command), I was surprised to see binary garbage rather than glistening, clear Matlab prose. Then I noticed the directory in which it was finding the .m file:
>> which decimate
/cvs/cds/caltech/apps/mDV/extra/linetrack_c_mcr/toolbox/signal/signal/decimate.m
See that "linetrack_c_mcr" directory? This is what is generated when a "compiled" (grumble) Matlab program is run--it decompresses itself into a subdirectory containing weird semi-compiled binary .m files. Unfortunately this is somehow getting incorporated into the matlab path. (I assume there is something in mDV that says "put all subdirectories into the path.")

I hate the Matlab compiler.
180   Fri Dec 7 14:14:48 2007 robMetaphysicsComputer Scripts / Programstdsread problems on Solaris

tdsread has developed a strange new illness, whereby it cannot read EPICS values from two subsystems at once (e.g., getting an LSC and SUS value simultaneously). I thought this might have something to with the fact that both losepics and iscepics are running on the same box,
but the same thing happens with IOO EPICS records, so that's not the culprit.

This is new behaviour, and it's only happening on the solaris machines. I suspect some ENV/cshrc juju has caused it, as the tdsread executable is the same one from April, and I don't think our EPICS infrastructure has changed otherwise. In the near term we can either try running the scripts on linux, or modify the IFO scripts to not do these types of calls.
179   Fri Dec 7 11:33:24 2007 waldmanOmnistructureOMCPZT wiring
The 2 pin LEMO connector has got an unmarked pin and a pin marked by a white half-circle.
The unmarked pin is connected to the side of the PZT attached to the mirror.
The marked pin is connected to the side of the PZT attached to the tombstone.
178   Fri Dec 7 00:02:26 2007 ranaSummaryIOOMC/FSS Frequency Noise
The FSS frequency noise is not very bad.

I compared the MC_F spectra between Hanford and the 40m using DTT and its 'User NDS' option.
After Sam, Jenne, and DavidM installed the new MC Servo some time ago, the MC_F spectrum here
has had some whitening before it goes into the DAQ (on board; same as LLO & LHO). The tuning
coefficient of the VCO is also basically the same between all PSLs since everyone has the same
chip in the VCO driver.

Therefore, at the frequencies where the MC gain is more than ~4, the MC_F signal calibration is
the same here as anywhere. Since its the servo control signal, its basically a measure of the
frequency noise incident on the MC -- its just what comes out of the FSS with the table noise on
top. At low frequencies (< 100 Hz) its a measure of the motion of the MC mirrors.

Above 200 Hz ours is the same as theirs; except for the enormous power line spikes. I think that's
either all on the light. But our acoustics are better and the noise above 1 kHz levels off at the
same flat floor (the phase noise of the VCO) as H1. The huge lump around 100 Hz is the MC2 DAC noise and
it goes down to the H1 levels when we flip on the dewhites. The giant excess from 5-50 Hz is just the fact
that our stacks don't do much until 20-30 Hz.

So we can stop blaming the FSS and move on with life as soon as Tobin gets the ISS back in shape.
177   Thu Dec 6 19:30:43 2007 tobinUpdatePSLISS dark noise - 60 Hz!
A higher resolution spectrum [attached] shows that nearly all of the excess dark noise on the ISS is in 60 Hz harmonics (with some 256 Hz harmonics too--are these from the DAQ?).

With the loop closed and the slider at 5dB, the laser light coming out has a noise floor of 10^-7 RIN or better from 40 Hz to 8 kHz.

Now to figure out why all this 60 Hz is getting in... (I tried turning off all the lights and the HEPA, and moving the SR785 further away, none of which did anything.)
176   Thu Dec 6 19:19:47 2007 AndreyConfigurationSUSSuspension damping Gain was restored

Suspension damping gain was disabled for some reason (all the indicators in the most right part of the screen C1SUS_ETMX.adl were red), it is now restored.
175   Thu Dec 6 18:11:15 2007 robHowToComputer Scripts / ProgramsMaking DMF monitors

I was able to use the matlab compiler to compile a version of the linetracker written by Rana, and run the compiled version on mafalda.

I believe I made the necessary edits to our mDV config file so that it should be easy for others to follow these steps:

1) Write the DMF routine you want, as a matlab function (not a script).

2) If it runs correctly in matlab, then from the matlab command line compile
it using the -m flag (i.e., mcc -m myfun.m). You should run the
compiler from the directory where you want the executable to end up (don't use the mDV/extra
directory so it doesn't get all cluttered).

3) prior to running the resulting executable (which should be called simply myfun),
prepend the directories
/cvs/cds/caltech/apps/linux/matlab/bin/glnx86
/cvs/cds/caltech/apps/linux/matlab/sys/os/glnx86/

to the LD_LIBRARY_PATH enviroment variable. These directories must be prepended as the
versions that already exist in /usr/lib don't work; I'm loathe to do this in the cshrc.40m
for fear of later conflicts, so it will need to be done in some sort of shell script which
calls the matlab executable.
174   Thu Dec 6 15:22:42 2007 AndreySummaryElectronicsPictures of the inside of He-Ne laser

Steve gave me an old "dead" He-Ne laser that long time ago was used for ETMX optical lever.

I dismantled it (cutting the metallic enclosure with a metallic saw), and these are two pictures of what is inside.
173   Thu Dec 6 15:21:59 2007 albertoFrogsElectronicsRF Transfer Function of Stiff Aluminum Wires
Transfer function of 3cm long Aluminum wires and of 3cm stranded wires
172   Wed Dec 5 23:19:03 2007 AndreyConfigurationPEMAccelerometers are turned on

All accelerometers have been turned on, as Alan asked during Wednesday meeting.

Typical power spectra and coherence plots are attached below.

"East" in the name means that the previous location of accelerometrs was to the east from "Beamsplitter" (the location for "east" accelerometers was not changed, actually, it is still near ITMX), while "west" means that previously accelerometers were to the west from the BS, but now their new location is near the ETMX.

I will change the names of the channels tomorrow (Thursday) when someone (Tobin?) will show to me how to do it.

P.S. (addition made on Dec. 19th, 2007, by Andrey) I intended to change the names of accelerometers the next day, Thursday Dec. 06,
but I did not do it that day (did not understand how to do it), then I fell ill, and eventually
I changed the names of accelerometers on December 19th, see entry to ELOG #204)
171   Wed Dec 5 20:32:51 2007 tobinUpdatePSLISS dark noise
The ISS dark noise is not coming from the PD heads; the spectrum is essentially unchanged when the PD is unplugged from the ISS. Did the input opamps both get semi-fried in the same way? (They worked so well when they were first installed.) What else changed? I'm baffled.
170   Wed Dec 5 19:25:07 2007 ranaDAQCDSDMF
I made a database file on C1AUX called dmf.db. It has 9 DMF EPICS channels which are also trended
so that one can now write data to those channels from a DMF Monitor and the data will be records.

New channels:
[C1:DMF-SEIS_1]
[C1:DMF-SEIS_2]
[C1:DMF-SEIS_3]
[C1:DMF-LINE_1]
[C1:DMF-LINE_2]
[C1:DMF-LINE_3]
[C1:DMF-MC_1]
[C1:DMF-MC_2]
[C1:DMF-MC_3]

I added these to C1AUX because it doesn't do much and can be booted without having much effect.
(it controls Mech Shutters, Video, and Illuminators. It used to also do the EO Shutter but I
removed that from its startup.cmd and it will no longer load those records).
169   Wed Dec 5 18:22:03 2007 tobinUpdatePSLISS dark noise
Attached is a plot of the dark noise spectrum of the ISS photodiodes (1) before fooling with them, (2) after replacing the 4151's with 4131's (improvement!), and (3) after replacing the cables and changing the wiring (disaster!).
168   Wed Dec 5 18:08:36 2007 AndreyUpdateASCOptical Lever laser for ETMX is installed

A new laser with \lambda=633nm has been intalled and the mirror adjusted so that the signal hits the center of the photodetector.

Output power level of that laser is 3.45 +- 0.05 mW.

Only about 0.29mW hits the photodetector.

Cable clips have been used to firmly fix the power supply cable for the laser.

See attached photopicture of the ETMX - "oplev" - optical - table.
167   Wed Dec 5 17:49:57 2007 tobinUpdatePSLISS
Attached is a plot of the ISS RIN with a variety of gain settings.

Unfortunately the dark noise is huge now--a result of the new cables & wiring?
166   Wed Dec 5 16:57:36 2007 tobinHowToComputer Scripts / ProgramsSR785 data converter on linux
I was pleased to find that the SR785 Data Viewer (including the command line conversion utility) installs and works in linux using WINE (on my laptop at least). There are some quirks, of course, but I was able to extract my data.
165   Wed Dec 5 13:49:08 2007 albertoUpdateElectronicsRF AM PD lines monitor
In the last weeks I’ve been working on the design of an electronic board to measure directly the power of the main spectral lines on of the RF-AM photodiode from as many independent outputs. The idea is to have eventually a monitor channel in the CDS network for the power of each line.
Looking at at the spectrum from the RF-AM PD (see attached plot), there are 5 main lines:
Frequency
3 fsr = 33 195 439 Hz
4 fsr = 66 390 878 Hz
12 fsr = 132 781 756 Hz
15 fsr = 165 977 195 Hz
18 fsr = 199 172 634 Hz

Two main approaches have been proposed for the circuit depending on the way followed to isolate the lines:
1) Filters: the frequencies are separated by narrow notch filters, then a diode bridge rectifies and a low pass filter extracts the DC component.
2) Mixers: for each frequency there is a mixer driven by a copy of the correspondent modulation frequency provided by the function generators (the Marconi). The mixers automatically give the DC component of the rectified signals.
Because of the phase lags that we should compensate if we used mixers, we would prefer the first approach, if it works.
Starting with a tolerance of about 10% between the channels, the spectrum (see attachment) sets the constraint to the filter’s suppression:
Filter central frequency [MHz]******Suppression within 30 Mhz [dB]
33*********************************-7-20 = -27
66**********************************7-20 = -13
133*********************************12-20 = -8
166********************************-12-20 = -32
199*********************************10-20 = 10

So far I’ve tried two kinds of designs for the filters, Butterworth (see attachment) and LC and I'm measuring transfer functions tuning the components to match the central frequency and the bandwdth of the filters with the requirements.

The frequencies we’re dealing with are rather high and several adjustments had to be done to the measurement system in order to shield the circuit from the impedance of the input and the output line (i.e., amplifier turned out to be necessary). Also, an the mixer had to be replaced to an RF one.
It seems I'm now measuring new transfer functions (which look quite different from what I've got with no amplifiers).
To be posted soon.
164   Wed Dec 5 10:57:08 2007 albertoHowToComputersConnecting the GPIBto USB interface to the Dell laptop
The interface works only on one of the USB ports of the laptop (the one on the right, looking at the computer from the back).
163   Tue Dec 4 23:16:35 2007 tobinUpdatePSLISS
I was confused to find that I could increase the ISS gain slider all the way from 15dB to 30dB without seeing much of any increase in gain in the measured open-loop transfer function. While making these swept-sine measurements, the saturation indicator almost never tripped, indicating it was seemingly happy. But then I noticed an odd thing: if I disable the test ("analog excitation") input, the saturation indicator trips immediately. I hooked up a scope to the current shunt test point (TP12). With the test input enabled, the loop closed, and the analog excitation port connected to the SR785, I see a a 5 Vpkpk, 2.55 MHz triangle wave there. It is there even if I set the SR785 excitation amplitude to zero, but it disappears if I disconnect the cable from the SR785.

I found oscillations at TP20, TP30, TP36, TP41, and TP42. Many of these are in the (unused) "outer loop" circuitry and currently lack compensation capacitors.
162   Mon Dec 3 22:20:09 2007 tobinConfigurationPSLISS
I replaced the painfully short 1' cables on the ISS photodiodes with luxurious five foot cables, made by chopping a ten foot Amphenol cable (P/N:CS-DSPMDB09MM-010) in half and using each half for one of the diodes. All of the ISS GND connections are wired to the PD GND, as is the PD- differential signal. The diodes are installed on the PSL table, but I have not tested them beyond looking at the DC values as I blocked/unblocked the beam.
161   Mon Dec 3 19:44:58 2007 Accelerometers on new mountsConfigurationPEMAndrey

I (Andrey) continued today working with new accelerometer mounting. (see entry #151 about my Friday work).

I bought screws/washers and attached those mounts with accelerometers to metallic frames which are firmly cemented to the floor.

One such mount with three accelerometers (in X-, Y-, Z-directions) is installed near the ITMX (in the previous location, but NOT on top of the unused stack as before Friday), the other mount with three accelerometers in three orthogonal directions is installed near ETMX in the east end of the room (this set of accelerometers was installed between MC and BS before Friday). I uncoiled the cables, put them into the cable tray towards the ETMX, and hooked-up the three accelerometers near ETMX in the east end of the room.

Now all six accelerometers are hooked-up (that is, connected to power supply board with cables).

We decided with Steve Vass to put red cones (similar to those that are on highways in the road construction zones) in order to prevent people from bumping into accelerometers. Please use caution when walking along the X-arm.

I took several pictures of the new accelerometer setup. Picture "DSC_0194.JPG" shows the mount with accelerometers near the the ITMX and the beamsplitter chamber,
picture "DSC_0195.JPG" is the "zoomed-in" view of the same accelerometers, while picture "DSC_0196.JPG" shows the mount with accelerometers near ETMX in the east end of the room.

Many thanks to Mr. Steve Vass for his thorough explanation/showing me how to drill the metal and put threads in the holes.
160   Mon Dec 3 19:06:49 2007 ranaDAQComputer Scripts / Programslinemon
I turned up my nose at Matlab's special tools. I modified the linetracker to use the
relationship phase = 2*pi*f*t to estimate the frequency each minute. The
code uses 'polyfit' to get the mean and trend of the unwrapped phase and then determines
how far the initial frequency estimate was off. It then uses the updated number as the
initial guess for the next minute.

I looked at a couple hours of data before letting it run. It looks like the phase of the
'60 Hz' peak varies at 20 second time scales but not much faster or rather anything faster
would be a glitch and not a monotonic frequency drift.

From the attached snapshot you can see that the amplitude (PZT1_PIT) varies by ~10 %
and the frequency by ~40 mHz in a couple hour span.
159   Mon Dec 3 17:55:39 2007 tobinHowToComputer Scripts / Programslinemon
Matlab's Signal Processing toolbox has a set of algorithms for identifying sinusoids in data. Some of them (e.g., rootmusic) take the number of sinusoids to find as an argument and return the "most probable N frequencies." These could be useful in line monitoring.
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.
157   Mon Dec 3 00:10:42 2007 ranaDAQComputer Scripts / Programslinemon
I've started up one of our first Matlab based DMT processes as a test.

There's a matlab script running on Mafalda which is measuring the height of the 60 Hz peak
in the MC1 UL SENSOR and writing it to an unused EPICS channel (PZT1_PIT_OFFSET).

The purpose of this is just to see if such a thing is stable over long periods of time. Its
open on a terminal on linux3 so it can be killed at any time if it runs amok.

Right now the code just demods the channel and tracks the absolute value of the peak. The
next upgrade will have it track the actual frequency once per minute and then report that
as well. We also have to figure out how to make it a binary and then make a single script
that launches all of the binaries.

For now you can watch its progress on the StripTool on op540m; its cheap and easy DMT viewer.
156   Sun Dec 2 21:13:16 2007 ranaConfigurationIOOMC SUS re-alignment
155   Sun Dec 2 21:07:39 2007 ranaConfigurationIOOMC SUS re-alignment
you asked for:   diff 2007/12/01,4:58:48 2007/12/03,4:58:48 utc 'MC.*COMM'
LIGO controls: differences, 2007 12/01 04:58:48 utc vs. 2007 12/03 04:58:48 utc
__Epics_Channel_Name______   __Description__________   __value1____     __value2____
C1:SUS-MC1_YAW_COMM                                    -0.273460        -0.503460
C1:SUS-MC2_PIT_COMM                                     3.624020         3.632020
C1:SUS-MC2_YAW_COMM                                    -0.936800        -1.038800
C1:SUS-MC3_YAW_COMM                                    -3.129000        -3.369000
154   Sun Dec 2 21:02:12 2007 ranaConfigurationIOOMC SUS re-alignment
The spot on MC2 was not centered, so I put it back in the center:

• Made sure MC trans was high with the WFS off.
• Moved the Sliders on the MC Align screen until spot was centered (by eye)
• Moved some more until power was maximized.
• Unlock MC
• Center spots on McWFS
• Re-enable autolocker and McWFS loops.
153   Sun Dec 2 17:37:33 2007 ranaOmnistructureComputersNetwork Cabling in the Office
We all know that we've spent many integrated man hours trying to figure out why our network connections
in the office area don't work. Usually its because of the bad hub around the Tobin/Osamu desk.

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

152   Fri Nov 30 21:27:24 2007 ranaDAQPEMweather / stacis / c1pem1
I was trying to add some Seis BLRMS channels to the c1pem1 processor so that we could have DMT trends.

Then I found that none of the Weather channels have been working for a year or so. I could also not
telnet into it. I tried resetting it but no luck. There was no entry in the Wiki for it so I added
a place holder.

Have the weather channels ever worked? Do we have those sensors? I think I've never actually looked
for this. Seems like a fine ugrad job.
151   Fri Nov 30 20:17:26 2007 AndreyConfigurationPEMAccelerometers and alum.plates for them
All 6 accelerometers which were located near the ITMX are turned off and disconnected from the power cords.
Actually these accelerometers are now in the office area on the electronics bench (to the left from Steve Vass' place).

I made today 4 new aluminum mounting plates for the accelerometers (I drilled holes and made threads in them). On Monday I will buy short screws and install accelerometers on these new mounting plates. These mounting plates will be screwed directly into the metallic frame which is firmly cemented to the ground. Before yesterday accelerometers were mounted on top of blue stack towers, not on the ground directly, so we hope that new measurements of the ground noise will be more realistic.

The 4 mounting plates are on the same desk -> on the electronics bench (to the left from Steve Vass' place). Please do not displace them.

Attached is a drawing of the aluminum mountain plate.
150   Fri Nov 30 20:13:57 2007 dmassSummaryGeneralHeNe UniPhase Laser
Data for the Uniphase 1.9 mW HeNe laser (labeled: "051507 From ISCT-BS") SN: 1284131 Model: 1103P

I used the Photon Beamscanner to obtain all data, then fit w(z) as shown on the plot with parameters w_0, z_R, and hidden parameter delta,
where z = delta + x, z is waist distance, x is distance from the laser.

Copies of the matlab code used to fit (/plot) are attached in .zip below.
149   Fri Nov 30 19:46:58 2007 ranaConfigurationComputersEPICS Time Bad again
The time on the EPICS screens is off by 10 minutes again. Por Que?

Its because the ntpd on scipe25 wasn't restarted after the last boot. If someone
knows how to put the ntpd startup into that machine, please do so.

This time I started it up by just going sshing in as controls and then entering:

sudo /usr/sbin/ntpd -c /etc/ntp.conf

which runs it as root and points to the right file.

It takes a few minutes to get going because all of the martian machines have to first fail to
connect to the worldwide pool servers (e.g. 0.pool.ntp.org) before they move on and try linux1
which has a connection to the world. Once it gets it you'll see the time on the EPICS screens
freeze. It then waits until the ntp time catches up with its old, wrong time before updating
again.

According to the Wikipedia, this time is then good to 128 ms or less.
148   Fri Nov 30 19:29:14 2007 ranaConfigurationSUSnew screen
Andrey is working on a new screen to show us the drift of the optics by alarming on
their osem values. You can find it under SUS as 'Drift Mon' from the site map.

To aid in this I ran the following csh commands which effect all optics:
foreach opt (ETMX ETMY ITMX ITMY MC1 MC2 MC3 BS PRM SRM)
foreach dof (POS PIT YAW)
ezcawrite C1:SUS-${opt}_SUS${dof}_INMON.PREC 0
end
end


147   Fri Nov 30 19:11:05 2007 ranaConfigurationElectronicsETMX oplev dead again
I removed the ETMX HeNe and put in on a test table and it fired up fine. In its
previous location the light on the HeNe power supply was not lighting up. If
that's still on over the weekend we'l blame the power strip; the HeNe is a JDS
2.7 mW laser from 2002.
146   Fri Nov 30 13:46:50 2007 robConfigurationElectronicsETMX oplev dead again

 Quote: In the interests of getting the Xarm alignment script working again, I reset the local damping gains for the test masses to their previous known working values (1), then I noticed that the ETMX oplev was dead. Since the scripts use the oplev motion as a readback for the optic motion, this means the script was basically blindly swinging the optics around. Some monkeying around with swapping HeNe power supplies eventually led to the conclusion that the power strip is funky, since the laser works when plugged into another power strip. Even weirder, the HeNe and the power supply indicator light have some sort of XOR relationship going on. When one works, the other doesn't. Steve will sort out this confusion later; we're good for now.

Ech. The HeNe quit again. Let's replace it and see what happens.
145   Fri Nov 30 11:44:57 2007 robConfigurationElectronicsETMX oplev
In the interests of getting the Xarm alignment script working again, I reset the local damping gains for the test masses to their previous known working values (1), then I noticed that the ETMX oplev was dead. Since the scripts use the oplev motion as a readback for the optic motion, this means the script was basically blindly swinging the optics around. Some monkeying around with swapping HeNe power supplies eventually led to the conclusion that the power strip is funky, since the laser works when plugged into another power strip. Even weirder, the HeNe and the power supply indicator light have some sort of XOR relationship going on. When one works, the other doesn't. Steve will sort out this confusion later; we're good for now.
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.

Download and installation instructions, as well as a few examples for use

https://www.gravity.phy.syr.edu/dokuwiki/doku.php?id=ligodv:home
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.
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.
141   Thu Nov 29 15:17:53 2007 robConfigurationPSLISS

I put some ISS beam on the diode on the PSL table. In the previous layout, this was the monitor diode (and it's labeled monitor) but I plugged it into the sensor jack anyways so we can run with the loop closed for now; we can just switch the cables later. The reason the beam was unclear is because someone popped up a flipper mirror which redirects the beam from the ISS into an OSA.

With the ISS gain slider at 15 dB the UGF is around 40kHz.

Why do we have such short cables for the ISS diodes?
140   Thu Nov 29 14:29:22 2007 tobinConfigurationComputerslinux1 httpd/conlogger fixed
I think I fixed the conlogger web interface on linux1.

Steps necessary to do this:
0. Run "/etc/init.d/httpd start" to start up httpd right now
1. Run "/usr/sbin/ntsysv" and configure httpd to be started automatically in the future
2. Copy /cvs/cds/caltech/conlogger/bin/conlog_web.pl to /var/www/cgi-bin and chown to controls
8. Hack the conlog_web.pl to (0) use /usr/bin/perl (1) not use Apache::Util, and (2) function with the newer version of CGI.pm
9. Enjoy!

The following steps are optional, and may be inserted between steps 2 and 8:
3. Try to install Apache::Util (via "perl -MCPAN -e shell" followed by "Install Apache::Util")
4. Notice that the installation dies because there is no C compiler installed
5. Bang head in disgust and abomination over a Linux distribution shipping without a C compiler installed by default
6. "yum install gcc"
7. Annoyed by further dependencies, go to step 8
139   Thu Nov 29 11:10:54 2007 robOmnistructureVACRGAlogger sleeping
Without the RGA controller responding, the RGAlogger script just hangs. Rather than fix it, I just put it to sleep by commenting out the line in op440m crontab file. Once we get it running again, we'll move the cronjob to op340m.
138   Thu Nov 29 10:36:47 2007 albertoConfigurationComputer Scripts / ProgramsAgilent 82357B GPIB to USB Interface Installation Procedeure
To run the Agilent Automation-Ready CD provided with the interface is only the first step of the installation. Apparently there should be also a second CD with the drivers for Windows XP but I couldn't find it. So, after Installaing the IO Libraries Suite from the CD, I had to install the drivers with an executable downloaded from the Agilent's website at:

http://www.home.agilent.com/agilent/editorial.jspx?cc=US&lc=eng&ckey=1188958&nid=-35199.0.00&id=1188958

and only then I could plug in the interface.
Anyway, I burned a cd with the file and put it together with the other one.
137   Wed Nov 28 21:51:52 2007 tobinConfigurationPSLISS
I replaced the front-end differential receivers for the ISS's "inner-loop" sensor and monitor diode inputs with lower-noise THS4131's (formerly THS4151's). I verified operation by taking the transfer function from the "PD+" and "PD-" inputs (separately) to the testpoint following the differential receiver; the surgery appears successful.

I measured the dark spectra at the ISS's DC PD BNC ports and found a noise floor of ~ 16 nV/rtHz, compared with a floor of ~ 22 nV/rtHz last week. This seems to add up, assuming the DC PD port has 0dB gain: the 4131 has a rated noise of 1.3 nV/rtHz and the 4151 a noise floor of 7.6 nV/rtHz, a difference of 6 nV/rtHz. The other change made in that time was to add a larger power supply bypass capacitor in the PD.

There are two of the old 4151 chips still on the ISS board on the two "outer-loop" channels that we don't use. If I dig up any more 5131's I will replace these too for completeness.

There is currently no light on the ISS diodes; I'm not sure where it's intended to come from.
136   Wed Nov 28 19:44:18 2007 tobinUpdatePSLHEPA
I found the HEPA turned off completely. I turned it on.
135   Wed Nov 28 19:02:41 2007 AndreyBureaucracyWIKI-40M UpdateNew WIKI-40M page describing Matlab Suspension Modeling

I created the WIKI-40m page with some details about my today's talk on the 40-m lab meeting.