The typical sign of a dying gas laser is that it glows for a few minutes only. The power supplies are fine.
Two new JDS - Uniphase 1103P lasers ( NT64-104 ) arriving on Monday, May 21
Yesterday I swapped in new He/Ne laser with output power 3.5 mW The return spot on qpd is large ~6mm in diameter and 20,500 counts
The spot size reduction require similar layout as ETMX oplev.
The oplev path is relayed and the spot size on the qpd is reduced. I still have to clean up and replace "Miki Mouse" lens holder.
There was no IP-ANG coming out of the chamber at this time!
...will be helpful for acquiring lock after the vent. We should install a camera at ETMX.
Jenne and Steve
Sony CCD in place needs alignment and ND filter
Something bad happened to c1sus and c1iscex ~20 min ago. They both have "0x2bad" 's. I restarted the daqd on the framebuilder, and then rebooted c1sus, and nothing changed. The SUS screens are all zeros (the gains seem to be set correctly, but all of the signals are 0's).
If it's not fixed when I get in tomorrow, I'll keep poking at it to make it better.
IOO Angle & IOO Position QPDs centered.
PMC trend of 400 and 1200 days
The Innolight 2W based PSL- IOO was implemented in the ~ summer of 2010
Mike Pedraza came by today to install a new wireless network router configured for the 40m lab network. It has a 'secret' SSID i.e. not meant for public use outside the lab. You can look up the password and network name on the rack. Pictures below show the location of the labels.
Mike P swapped in a new network router Linksys E1000
For some reason the state of the oplevs is completely different for almost every suspension. They have different sets of filters in the bank, and different filters engaged. wtf? How did this happen? Is this correct? Do we expect that the state of the oplevs should be different on all the different suspensions? I wouldn't have thought so.
I discovered this because the PRM is unstable with the oplevs engaged. I don't think it was yesterday. Is something hidden changing the oplev settings?
As of February 23, 2012 when oplev PIT and YAW transfer functions were taken
What not to do:
The PRM oplev servo was left on and it was driving this oscillation overnight.
The ref cavity ion pump was running at 7.7kV instead of 5kV
This Digitel SPC-1 20 l/s ion pump should be running at 5kV
I noticed that the ion pump was turned off.
It was turned ON. It showed 0.00 microA at 5kV The current display is not sensitive enough. There must be some small outgassing or leak. It adds up if we stop pumping.
We want to keep the reference cavity in pristine condition. It required the ion pump running all times.
Air conditioning maintenance is scheduled for tomorrow from 8 to 11am
Oplev servo turned off and sus damping restored. What is kicking up the PRM?
from Apple Store on line
Late entry for Monday morning June 4, 2012
Cables were stress relieved. Cable entry - exit ports enlarged. Air gaps were minimized.
The PRM oscillation stopped by turnig off oplev servo.
Do not turn Oplev Servo on when PRM is missaligned !
Jeff checked and replaced filters as needed. Job completed this morning.
We tried not to open chambers above 10,000 particles of 0.5 micron cf/min
New items going in: 2 rasor beam traps, 5 badly oxidized old silver plated setscrew with spring loaded tips......to be replaced in the future, viton tips for eq screws....some are lose, gold plated allen wrench installed at ITMX bottom, reglued magnet on ITMX
Bad hardware things found: nylon ball "locking elements" on OSEM locking set screws with screwdriver slot, lose 1064 nm filter on OSEM pd
40m - pumpdown 71- maglev pumping speed - at day 276........all normal
The PMC was locked and the MC followed intantly
Yuta claims he fixed the PRM oplev by centering it the other day, but no one has left it on and watched it for a long while, to make sure it's okay. We watched it now for ~2 min, and it was good, but we're leaving the oplevs off anyway for the night. Tomorrow we should restore PRM (it's currently restored), turn on the oplevs, and let it sit to make sure it doesn't go crazy.
PRM oplev servo was turned on with PITgain 0.5 and YAWgain -0.7
Note: gain settings were PIT 1.0 and YAW --0.5 on Jun 1, 2012 that I measured Feb 23, 2012
It is still oscillating. Gains turned down to zero.
The MC_ IDC 64 pin cables from sat. amplifiers to junction-interface-board towards whitening - dewhitening at the back of rack 1 X 5 are finally clamped with
All other sus cables of the same kind have the correct short latch arm to lock them in for reliable contact.
There is a small wood cabinet under the south end flow bench, labeled STACIS.
Unit is complete with extension cards and cables.
The south end flow bench HEPA filter should be run all times. You can turn it off for a measurement or two but remember we are storing clean optics there.
The zero count bench will reach room particle count ~ 10,000 in one minute.
Masha, Eric, Yaakov, Liz and Sasha received 40m specific basic safety training.
I was notified by CIT Utilities that there was a power surge or short power outage this after noon.
Lab conditions are normal: c1ioo is down. The south arm AC was off......I turned it back on.
CALIFORNIA INSTITUTE OF TECHNOLOGY
UTILITY & SERVICE INTERRUPTION
Date: Saturday, June 23, 2012
Time: 3:46 P.M.
Interruption: Electrical Power Disturbance
Contact: Tom Brennan, x-625-395-4984
*The City of Pasadena Water & Power Department had a 34,000-volt line event on Saturday June 23 at 3:46 p.m. This caused a city wide disturbance on the power grid. The Campus did not lose electrical power. However, the disturbance may have affected sensitive electronic equipment.
(If there is a problem with this Interruption, please notify the Service Center X-4717 or the above Contact as soon as possible.
If no response is received we will proceed with the interruption.)
Interim Director of Campus Operations & Maintenance
Steve, Yuta and Jamie
Jam nuts were checked and oplev servos were turned off. Sus summery is below with strain gauge values. Are the strain gauge values have any meaning when the PZT contorrels are off??????????????????
The 4 hrs vent plot at 3 torr/min rate.
Nitrogen was used from 1e-6 torr to 35 torr at intake pressure 14 PSI
The rest was filled with 5 cylinders of Instrument Grade Air at intake pressure 14 PSI
We can start opening chamber at 3 pm today
We could set up a simple pick off after the Faraday and bring it out the north window of IOO chamber. No monitor needed, just take the cover off when you want to see it.
Most people have no idea how to get the MC through the F
Vacuum Normal State is reached in 9 hours. CC1 = 2e-5 Torr
Aux dry pump #3 is still running. The RGA is not pumped yet.
Why do we have these timing blanks?
I'm looking for some movement indicators of the vent-pump down events.
I can not understand what really happened here with CC1 gauge or there was really a pressure glitch.
attachment 1, pump down day 3 with 4th of July fireworks in the lab
attachment 2, before and after vent in 9 days
TP2 dry_pump was changed at intake pressure 982 mTorr at 84,889 hrs This seal hold up for one year.
The rebuilt pump seal performing well at 28 mTorr
Our cold cathode 423 gauges are 10 years old. They get insulated by age and show no ionization current. We should replace them at the next vent. I'm buying 4 at $317ea
The PMC was locking right the way, but it's transmission would not go up. Finally I get it back up by moving the "sticky" DC Gain slider up and down a few times.
We have two CC1 gauges at the pump spool. One is in vertical position and the spare is in horizontal. Today I switched the cable from vertical to horizontal CC1
This one is reading higher pressure. It is an old dirty gauge. It may trigger the RGA protection when it's reading goes above 1e-5 torr
The real pressure is 2e-6 torr
cc1h spikes closed VM1 last night. VM1 is opened.
SOS optics prepared to be hanged are moved from the South Flow Bench to S15 Clean Cabinet.
SRMU 03 (1-25-2010) specification summery E080460-05-D, older vintage SRM 01 and PRM 02 (need more specification)
There was one NOT MARKED SOS with two broken magnets on its face. This is labeled ???
This was done to prepare clean space for TIP-TILT drive- test set up.
The existing cable from 1X5 can reach only to the south end: from whitening filter to satelite amp. This will be good for future test of suspensions.
We need to make new cable from 1 X 1 to the south end = 40m long
Earthquake test our suspensions PRM damping restored. Oplev servo gains turned to zero.
. Power outage turned off the PSL Innolight laser on Sunday afternoon. It was turned back on and locked happily right on. The green lasers were not effected.
CALIFORNIA INSTITUTE OF TECHNOLOGY
UTILITY & SERVICE INTERRUPTION
Building: CAMPUS WIDE
Date: SUNDAY, AUGUST 6, 2012
Time: 3:41 PM
Interruption: ELECTRICAL POWER DISTRIBUTION
Contact: MIKE ANCHONDO, X-4999, OR TOM BRENNAN, X-4984
* THIS PAST SUNDAY AFTERNOON ABOUT 3:40 PM, PASADENA WATER AND POWER
EXPERIENCED A FAULT ON THEIR POWER DISTRIBUTION SYSTEM. THIS CAUSED
A SEVERE VOLTAGE SAG WHICH AFFECTED THE CALTECH CAMPUS. THE FAULT WAS
NOT ON A CALTECH CIRCUIT.
(If there is a problem with this Interruption, please notify
the Service Center X-4717 or the above Contact as soon as possible.
The power outage did not have any effect on the vacuum system. I had to open VM1 to the RGA because of flaky CC1 cold cathode gauge fluctuations.
We are running on the vertically positioned CC1 again.
Note: rga scans with closed VM1 are back ground scans.
The SRM oplev beam is clipping.
Sanwiched wall as shown: 1" clear acrylic, 2 layers of 0.004" thick "window tint", 1 layer of 0.007" thermashield and 0.125" yellow acrylic
Visibility: 70 %, Transmission of 1064 nm 2-3 % at 0-50 degrees incident power density 0.7 W/mm2
Max power 100 mW
Caltech security called me at 1am Sunday. Control room emergency exit door was found unlocked!
It is your responsibility to lock door if you unlocked it !
I'm proposing larger optical tables at the ends to avoid the existing overcrowding. This would allow the initial pointing and optical level beams to set up correctly.
The existing table is 4 x 2 would be replaced by 4' x 3' We would lose only ~3" space toward exist door.
I'm working on the new ACRYLIC TABLE COVER for each end that will cost around $4k ea. The new cover should fit the larger table.
Let me know what you think.
The drawing of the 4' x 2' table cover can be seen at entry #6190 The new proposed wall #7106 The yellow acrylic would be ~ 0.25" thick and it will be the inside. It is not shown on the drawing.
Question remaining: should get a larger table 4' x 3' as outlined by red lines and make new cover to fit this
The oplev beam path needs larger incident angle to get in and out of the chamber: REMOVE BOTTLENECK for easy traffic
Moving the existing table closer to ETMY chamber - as Jamie suggested- would help but there is no room for this solution.
The larger table solve this issue and leave more room for initial pointing, arm transmitted and future experiments.
Other benefits: no tube to make between table and chamber. It is easier to make the the larger box air tight.
The new isolation box with feed through, cover, seals will cost $4-5K ea
Reinforced concrete grout plate for existing carbon steel stands at the ends.
I did relayed the oplev path with new f 500 mm lens
We can only decide the need of pitch damping when the coils are activated.
Could you tell us why? Are you thinking about induced current damping?
I was wrong The instability will be the same when the coils are actuated.
The PRM damping restored. Oplev PIT gain 0.15 and YAW gain -0.3 turned to zero.