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ID Date Author Type Categoryup Subject
  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.
  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?
Attachment 1: rin.pdf
  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!).
Attachment 1: sense_noise.pdf
  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. Frown
  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.)
Attachment 1: iss.pdf
  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.
  185   Mon Dec 10 18:42:20 2007 tobinUpdatePSLISS RIN script
I wrote a script to measure the ISS RIN. The script uses the "labca" interface (described in an earlier entry) to read and twiddle EPICS settings and mDV to get DAQ data. The script measures open loop RIN, closed loop RIN at each of several gain slider settings, and dark noise. The dark noise is obtained by misaligning (unlocking) the PMC. The script also compares the whitened and unwhitened spectra for an open loop measurement and performs a fit of a simple pole to find the dewhitening filter.

This is all very exciting, but I don't quite believe the results, since the closed loop RIN seems to bottom out at 2e-7/rtHz regardless of the gain slider setting.

Sample output attached. The script may be found at scripts/PSL/ISS/rin.m.
Attachment 1: rin-20071210-1831.pdf
  186   Mon Dec 10 19:08:03 2007 tobinConfigurationPSLMZ
The MZ seems finicky today--it keeps unlocking and relocking.

I've temporarily blocked one of the MZ arms while I work on the ISS.
  197   Tue Dec 18 21:31:31 2007 tobinUpdatePSLISS RIN
My measurements of the ISS RIN via the SR785 and via the DAQ disagree considerably. The spectral shapes are very similar, however, so I expect that a constant factor is creeping in somewhere. Measurements taken at the PD DC monitor points using the SR785 attached. There is a lot of excess noise in the 300 Hz - 1 kHz region.
Attachment 1: iss-rin.pdf
  211   Sat Dec 22 00:52:57 2007 tobinConfigurationPSLISS surgery
In an attempt to quell oscillations in the (unused) outer loop portion of the ISS, I shorted the "PD+" and "PD-" signals from the (nonexistent) outer-loop diodes, and soldered in 47pf compensation capacitors in C92 and C220. This seems to have eliminated oscillations seen at TP41 and TP42. There's still something amiss at TP30 and maybe TP20. Otherwise, the ISS seems happy. I can turn the gain slider to +15dB without saturation (with the HEPA off), though there seems to be less light on the diode (~3.9V) than a week or two ago.
  221   Thu Jan 3 09:12:59 2008 steveUpdatePSLMZ servo
Here is MZ trend for one year and 40 days.
Now days it runs out of range on the low side.
This is the weakest link in the psl today.
Attachment 1: mz1y.jpg
Attachment 2: mz40d.jpg
  293   Fri Feb 1 17:17:05 2008 JohnSummaryPSLMach-Zender tweaking
I helped Rob adjust the alignment of the Mach-Zender to try and reduce any AM on the laser light. Our goal was to reduce the large offsets in the DD signals.

We reduced the MZ refl from 0.54 to 0.39. We were able to re-lock the mode cleaner without problems. We then centred the WFS heads.

No change in the DD signal offsets.
  325   Wed Feb 20 11:34:17 2008 steveUpdatePSLlaser head temp is up
MOPA head temp is running at 20.3C now
Nomally it is at 18.5C
Attachment 1: htempup.jpg
  326   Wed Feb 20 16:24:37 2008 steveUpdatePSLthe laser is recovering slowly
Head temp is still 20.5C and decreasing slowly.
Power output 2.9W
NPRO power 22 mW is increasing as head is cooling down
Attachment 1: laserecoverring.jpg
  327   Thu Feb 21 09:56:26 2008 steveUpdatePSLthe laser is back
The laser and the psl recovered.
The water chiller temp is 19.98C and head temp 18.4C
Power 3.2W
PMC_T 3.1

c1iovme was restarted and the mc is locking now
Attachment 1: laserisback.jpg
  365   Fri Mar 7 19:04:39 2008 steveOmnistructurePSLlaser pointer
Green laser pointer was found in my desk.
I blamed Rana for not returning it to me after a conference talk.
It is surprisingly bright still.
I will bring sweets for Wednesday meeting.
  450   Fri Apr 25 15:44:21 2008 steveUpdatePSLscattering measurments
In pursuit of a low back scattering, high power beam dump we looked at materials such:
polished copper, polished aluminum, diamond cut aluminum, variety of polished & heat treated stainless steel and shades of black glasses.
Black glass is ideal at low power. Superpolished SS 304 #8 is the only material that measures close to bg
We are still looking for a conductive low back scattering material that would be ideal for a good high power beam trap.

Black glass-shade 12, ss304 superpolished #8 and white paper-B98-24lbs back scattering were compared at 1064 nm

Atm 1: data plot numbers from front panel of SR830 display,
sensitivity: 1x1 mV for bg and ss
1x1 V for wp

Atm 2: drawing of measurement set up
Atm 3: SR830 lock.amp settings
Atm 4: view from steering mirror
Atm 5: view from black glass trap
Atm 6: white paper
Attachment 1: scatmeas20080425.xls
Attachment 2: scattring_set_up_20080425.ppt
Attachment 3: sr830settings.pdf
Attachment 4: viewfmirror.pdf
Attachment 5: viewfbgtrap.pdf
Attachment 6: wpnmount.pdf
  479   Thu May 15 12:05:49 2008 josephbConfigurationPSLPath to PSL Position QPD
The 50/50 beamsplitter that was being used as the last turning mirror to the PSL Position QPD has been replaced with a Y1-1037-45-S plate. This turning mirror was also moved 4" farther along the beam path, so as to produce as small (few microwatts) transmission through the plate. The lensing optics were also shifted so as to maintain a focused beam on the photodiode. Lastly, the rotating ND filter was increased from 1.5 to 2.0 to reduce the incident power on the photodiode, since twice the power is now reaching it.

The small beam on transmission will be used by the digital cameras as a test beam.
  497   Sun May 25 20:30:25 2008 ranaSummaryPSLPMC Mode Matching
I checked the PMC mode matching by ramping the gain down to -10 dB (from +20 dB) and
moving the DC offset around until it caught lock on the different HOMs. Then I recorded
the output power (PMCTRANSPD). The DC offset on this EPICS channel was -0.013 V, so I
used its AOFF field to zero this out. Here is a list of the power in the largest modes:
Mode    Power (V)
----    ---------
00        2.7
10        0.2
04        0.04
02        0.02
BE        0.36      **Bull's Eye mode is TEM02 + TEM20. This can be fixed by lens adjustment.

N.B. To make a PNG file with DTT, just make an EPS file -- then use the eps2png perl script.
Attachment 1: pmc.png
  502   Wed May 28 14:19:47 2008 steveUpdatePSLkaleidoscope of psl
atm 1: scattering psl table optics from the top of the output periscope f4, 60s @MOPA 3 W
atm 2: scattering psl table optics from the top of the output periscope f4, 20s
atm 3: competing GigE cameras on the north end of psl table
atm 4: yellow "soft" washer to be replaced on psl output periscope
atm 5: ETMY-ISCT in disarray
Attachment 1: pslscat.png
Attachment 2: pslscat2.png
Attachment 3: 2GigEs.png
Attachment 4: perwash.png
Attachment 5: etmydisarray.png
  516   Wed Jun 4 10:18:52 2008 steveUpdatePSLwedged SS beam trap
I moved the SS trap over to the psl table.
Texas super # 8 was used from the large shipment.
TXs#8 scattering measured as before, meaning the polishing is good.

Go's squeezing power pick up 350 mW was used.
I made two ~30 degrees wedge traps using 6" x 4" and 12" x 4" SS 0.039" thick
with copper backing of similar size.

There was too much scattering and I could not minimize them all.
It is very helpful to have so much space on the psl table.
It shows more of the weakness of this kind of trap.
I did not dare to turn up the power.
Attachment 1: trap1.png
Attachment 2: trap2.png
  524   Fri Jun 6 16:10:51 2008 steveUpdatePSLHEPA filters are running at 100%
The psl HEPA filters were turned up to run at 100% to accommodate beam trap work on Tuesday, June 3, 2008
  526   Mon Jun 9 17:32:14 2008 YoichiConfigurationPSLPMC transmittance
I checked the current PMC transmissivity at a low power.
The input laser power to the PMC was reduced to 75mW by rotating the HWP in front of the PBS.
In this configuration, the output power from the PMC was 50mW. So the transmittance is about 66%.
The reading of C1:PSL-PMC_PMCTRANSPD is now 0.1 whereas it was 2.7 before turning the power down.

I will check the transmittance at a higher power when I get the cable for the 35W calorie meter, which is missing now.
  527   Mon Jun 9 17:57:59 2008 YoichiConfigurationPSLPMC input power backed to the original
I rotated back the HWP before the PBS to restore the input laser power to the PMC.
Now the reading of PSL-PMC_PMCTRANSPD is 2.7.
  528   Tue Jun 10 08:37:18 2008 steveUpdatePSLbeam trap is being tested
High power beam trap is being tested just west of FSS area on psl enclosure.

When the pmc is operating at low power that means that the rest of the 3W is going into the
circular SS trap.

Please beware of the high power beam trap test
Attachment 1: trapss3w.png
  529   Wed Jun 11 11:45:25 2008 steveUpdatePSLss trap works
The trap works well at 3 W level. No back reflected beam coming out of the trap on low power
sensing card level. The back scattering was not measured. The trap is insensitive to small pointing variations.
The SS surface did not show any visible degradation after 16 hrs of 3w exposure at elliptical beam size 4x8 mm

It is ready to be placed into the 35 W beam.
Attachment 1: P1020534.png
Attachment 2: P1020533.png
  534   Fri Jun 13 11:17:25 2008 YoichiUpdatePSLPMC transmittance at high power
We received a new cable for the Scientech calorimeter. So I measured the transmittance of the PMC at higher power.

Input power = 2.298W
Output power = 1.364W
Transmittance = 59%

The input power to the PMC was measured between the two mode matching lenses by the calorimeter.
2.298W looks a bit too low. Actually, the calibrated monitor PD on the MEDM screen shows about 3W output from MOPA.
So we (me and Steve) measured the power right after the PBS after the periscope from MOPA with the HWP set to maximize the transmission of the PBS.
It was 2.77W. According to Steve's previous measurement, the first mirror of the periscope transmits about 200mW of the incoming light to the monitor PD. So the actual output of the MOPA is about 2.97W, which is consistent with the monitor PD reading.
The aperture of the EOM for the PMC control is glowing a lot. We suspect this is the main cause of the loss (from 2.77W to 2.298W).
We may want to re-align the EOM.

The output light from the PMC was picked off by a glass slide. The reflectance of the glass slide was measured first at a lower power (input 98mW, reflected power 1.58mW). Assuming that the reflectance is the same for the higher power, I turned up the input power to the PMC. This time, the picked off power was 22.45mW. This means the actual output power is 98/1.58*22.45=1364mW. The glass slide was kept at the same angle through out the measurement.
The measurement of the output power was done by the Ophir power meter. So calibration difference between the Ophir and the calorimeter may introduce some error.
  536   Tue Jun 17 22:00:53 2008 JohnHowToPSLProblems turning MZ servo on/off
We were unable to toggle the MZ servo on/off (Blank/Normal) from MEDM. Pushing on the Xycom board and cables changed the fault from constant to intermittent. At least one lock loss has been caused by a MZ glitch.
  537   Wed Jun 18 00:19:29 2008 robUpdatePSLMOPA trend
15 day trend of MOPA channels. The NPRO temperature fluctations are real, and causing the PMC to consistently run up against its rails. The cause of the temperature fluctations is unknown. This, combined with the MZ glitches and Miller kicking off DC power supplies is making locking rather tetchy tonight. Hopefully Yoichi will find the problem with the laser and fix it by tomorrow night.
Attachment 1: MOPAtrend.png
  540   Wed Jun 18 18:20:10 2008 YoichiUpdatePSLInvestigation on the NPRO temperature stabilization glitches
As Rob pointed out in http://dziban.ligo.caltech.edu:40/40m/537 the MOPA NPRO has been showing some glitchiness in the LTEC loop.
Following Rana's suggestion, Steve and I opened the MOPA and directed a heat gun for a minute to the NPRO hoping that we can see something in the LTEC loop.
The first attachment shows the behavior of LTMP and LTECH along with DTMP and DTECH at the time of the heat gun attack.
T=0 is the time when Steve directed the heat gun to the NPRO. There is no response neither in LTMP nor LTECH.
DTMP and DTECH look like responding.
Around the center, there is a dip in LTMP. This might be caused by removing the heat gun. But we are not sure. This kind of small glitches can be found in LTMP everywhere (see the attachment 2).
It looks like the LTMP sensor is not working, or the LTECH loop is actually working but the LTECH reading is broken.
However, the scan of the slow actuator (temperature) shows the LTECH loop is actually working. So it is a bit confusing.
More investigation is necessary.
See the next entry by me.
Attachment 1: LTEC-loop-HeatGun-Response.pdf
Attachment 2: LTMP-glitches.pdf
  541   Wed Jun 18 18:26:19 2008 YoichiUpdatePSLFinding the optimal operation temperature for the NPRO by the slow act scan
Being suspicious of the temperature stabilization of the NPRO crystal, I ran the slow scan script written by Rana to find the suitable operation temperature.
The procedure is the same as the one explained in the entry below:
The attached plots show the results. By looking at C1:PSL-126MOPA_126MON, I set the slow slider voltage to 0.
This time, it looks like the temperature control of the NPRO crystal is working fine.
Obviously, PMC picks up many higher order modes. I will try to mode match/align the PMC later.
Attachment 1: FSS-slow-scan.pdf
  550   Fri Jun 20 17:42:48 2008 steveUpdatePSLSS trap scattering compared to black glass trap
Circular SS304 trap was compared to wedged black glass trap.

The measurement set up of entry 529 was changed to define polarization.
CrystaLaser was remounted in horizontal position and half wave plate was placed after it.
These measurements were done in horizontal polarization.

atm1: the cSSt and wBGt was moved horizontally, ~90 degrees of the incident beam
atm2: traps were rotated around the incident beam, ~20 degrees each direction
atm3: set up
atm4: top view of traps
atm5: side view of trap
Attachment 1: cSSt_1.png
Attachment 2: cSSt_2.png
Attachment 3: scatset_61908.png
Attachment 4: cSSt&wBGt.png
Attachment 5: cSStbeam.png
  569   Wed Jun 25 18:03:21 2008 YoichiConfigurationPSLFSS Input Offset slider problem
While working on the PMC scanning, I noticed that the FSS input offset slider is doing nothing.
I traced the signal flow and checked the cables/boards.
The slider changes the output voltage from a VMIVME4116 DAC in the PSL rack. This output voltage is confirmed to be correct at the FLKM64 connector. The signal is connected to the FSS servo interface box (D040423) trough a ribbon cable. However, the output from the interface box is always -27V regardless of the slider position.
Therefore, either the interface box (D040423) or the ribbon cable has a problem.
I will debug the interface box using an extension card when no one is working on the interferometer.
  575   Thu Jun 26 18:24:28 2008 YoichiUpdatePSLFSS input ofset slider problem - fixed
I checked the FSS servo interface board and found that a LT1125CSW used to differentialize offset channel was broken (no virtual short).
So I replaced it. Now the slider is working.
The op-amp was hitting the rail. So it seems like we had been applying the maximum offset to the FSS input all the time.
The reason why the FSS loop still worked with the large offset is that the applied offset (~14V) is attenuated by a factor of 500 at the summing point.
  591   Sun Jun 29 11:31:52 2008 JohnSummaryPSLISS
I reduced the gain of the ISS (C1: PSL-ISS_VGAGAIN) from 5dB to 2dB. Any higher and it constantly saturates.
  595   Sun Jun 29 19:53:26 2008 JohnSummaryPSLISS

I reduced the gain of the ISS (C1: PSL-ISS_VGAGAIN) from 5dB to 2dB. Any higher and it constantly saturates.

Seemed to go back to normal after the frame builder came back.
  597   Sun Jun 29 20:29:48 2008 ranaUpdatePSLCorrelation of PSL SLOW control v. Room temperature
Attachment 1: slowtemp.png
  602   Mon Jun 30 13:48:47 2008 John, RobConfigurationPSLDon't put the bin in front of the air conditioning unit
We spotted that the laser power was dropping.

The air conditioning unit was blocked by the blue bin/trash can/cestino causing the laser head temp to increase by 2 degrees.

Let's be careful about this in the future.
Attachment 1: binremoval.png
  603   Mon Jun 30 14:07:26 2008 RobConfigurationPSLDon't put the bin in front of the air conditioning unit

We spotted that the laser power was dropping.

the offending configuration:
Attachment 1: DSC_0140.png
  604   Mon Jun 30 15:08:52 2008 JohnSummaryPSLMZ alignment
I adjusted the alignmnet of the Mach-Zehnder's two North mirrors (downstream of the EOMs).

MZ REFL is reduced from 0.54 to 0.43. The largest improvement was due to pitch on the PZT mirror.
Attachment 1: mzalign.png
  607   Mon Jun 30 18:36:01 2008 YoichiUpdatePSLMZ alignment again
John, Yoichi

We re-adjusted the MZ alignment. The reason behind this is to make sure that the MZ dark port is not falling at a strange fringe, where it is only dark at the dark port PD. It can happen when the two beams poorly overlap.
We tried both the minimization of the MZ dark PD and the maximization of the MZ transmission at the same time.
We also placed another PD in the MZ dark port at a different distance from the original dark PD and tried to minimize this too.
If the MZ dark port is at a strange fringe, one of the dark PD can be dark where the other one is still bright.
If both of the dark PD get dark, the overlap between the beams should be ok.
We tweaked only the two mirrors of the MZ after the EOMs (mainly the one with a PZT).

Right now, the MZ dark power is 0.432.
BTW, we should change the name of the MZ dark port on the medm screen (it is now MZ reflection, where it is not a reflection).
I will try to change it later.

We wanted to put the beam position on the IOO-QPD_POS_* back to the original (before John tweaked the MZ alignment earlier).
However, the trends of IOO-QPD_POS_* show a lot of fluctuation and jumps, of which we don't know the cause. So we could not find reasonable original values.
We suspect a circuit problem in IOO-QPD_POS, especially because the jumps are very strange.
We will do this investigation later too.
  609   Tue Jul 1 10:15:22 2008 steveUpdatePSLeventfull two days
The laser recovered from a short temp rise. The MZ was aligned and realigned. The suspentions were kicked up accidentally.
Now the computers are down.
Attachment 1: 2d.jpg
  611   Tue Jul 1 11:57:24 2008 YoichiConfigurationPSLMZ servo switch problem again
C1:PSL-MZ_BLANK switch (to turn on/off the servo) is not working again. The switch is always off regardless of the epics state.
I pushed the cables into the xycom card, but it did not fix the problem.
  612   Tue Jul 1 12:08:38 2008 John, JoeConfigurationPSLPMC input PD
Joe and I switched cables so that the PMCR screen actually shows reflection not transmission.

The trans camera had a BNC connected to "video out" labelled PMC input PD. The video signal
going to the monitors does not come from "video out", it comes out the "DC in/sync" cable.
As far as we can see this diode doesn't exist. Where should the PMC input PD BNC cable be
  616   Tue Jul 1 16:48:42 2008 rob, johnConfigurationPSLMZ servo switch problem resolved forever

C1:PSL-MZ_BLANK switch (to turn on/off the servo) is not working again. The switch is always off regardless of the epics state.
I pushed the cables into the xycom card, but it did not fix the problem.

We have fixed this problem forever, by totally disabling this switch. Looking at the schematic for the MZ servo and the datasheet of the AD602, we found that a HI TTL on pin 4 disables the output of the AD602. Since the MZ servo was stuck in the off position, this seemed to indicate that it may be the XYCOM220 itself which is broken, constantly putting out a +5V signal regardless of the EPICS controls. We thought we might be able to get around this by disconnecting this signal at the cross-connect, but ultimately we couldn't find it because there is no wiring diagram for the Mach-Zehnder (!). So, we pulled the board and wired pin 9A of P1 to ground, permanently NORMALizing the MZ_BLANK switch. John has marked up the schematic, and someone should modify the MEDM screen and check the new screen into svn.

We can still the turn the MZ servo on and off by using the test input 1 switch.

Someone also will need to modify the MZ autolocker to use the test input 1 (MZ_SW1) instead of the old MZ_BLANK.
  618   Tue Jul 1 21:45:48 2008 JohnUpdatePSLMach Zehnder script and screen
I've edited C1: PSL_MACH_ZEHNDER.adl and /cvs/cds/caltech/scripts/PSL/MZ/lockMZ
to reflect the changes described in entry #616.
  639   Mon Jul 7 13:49:27 2008 YoichiHowToPSLMZ offset, gain tips
John, Yoichi

This morning John found that MZ servo is not working.
We were able to bring the MZ back by changing the output offset a bit. But we were not sure what was actually wrong.
So we pulled out the MZ board and checked several TPs to understand the behavior.
Here is the summary of what we learned this morning.

The MZ control board has the following stages:

[Mixer] -(error signal)-> [Sum amp for input offset] -(error + offset)-> [Variable Gain Amp] -> [Filter (x100 DC gain)] -(FB signal)-> [High Voltage Amp] -> output
(The HV amp also works as the sum amp for the output offset)

(1) We noticed that the Sum amp for the input offset has an output of -0.14V even when the offset input is 0V. This can be canceled by the input offset slider.
So for the moment, it is fine. But we might want to change the op-amp because the weird offset implies there might be something wrong with the chip.
The procedure to null the -0.14V offset is the following:
a) Enable Test 1 input on the MZ MEDM screen.
b) Move the input offset slider until the mixer monitor becomes 0V. Currently the input offset slider is at -7.5V to cancel the -0.14V offset.

(2) Because the gain of the Variable Gain Amp and the Filter combined is large, the Filter can be easily saturated if the output offset is not right.
This was the cause of the MZ problem this morning. The output offset slider was at a wrong position making the error signal slightly off centered from zero.
This residual DC error signal was amplified by the large gain chain and saturated the filter amp.
Our experience is that the output offset cannot go below -3V. We set it at 0V for now.
  642   Mon Jul 7 16:30:08 2008 steveUpdatePSLPSL-PEM 16 days trend
This morning the laser head temp was up to 20.3C because the laser chiller was overflowing.
I removed 700 cc water.

The PSL-FSS_RMTEMP became much more stable during the holidays as the psl enclosure was closed for 4 days

The high particle counts can be explaned by construction activity today.

The PMC & MZ PZT high voltages were out of range this morning.
Attachment 1: pempsl16d.jpg
  645   Tue Jul 8 08:16:56 2008 steveUpdatePSLPMC problem
The PMC is unhappy. PMC auto locker is not working.
DC output slider adjust has to be moved from rail to rail before it locks.

MZ is working great.
Attachment 1: pmc.jpg
  648   Tue Jul 8 12:25:54 2008 JohnSummaryPSLISS gain set to 2dB
ELOG V3.1.3-