ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
14978
|
Fri Oct 18 18:13:55 2019 |
Koji | Update | safety | Laser interlock looks OK | I've checked the state of the laser
interlock switch and everything looked normal. |
|
14977
|
Fri Oct 18 17:35:07 2019 |
gautam | Update | SUS | ETMX sat box disconnected | Koji suggested systematic investigation
of the ETMX suspension electronics. The tests
to be done are: |
|
14976
|
Thu Oct 17 16:49:53 2019 |
gautam | Update | ASC | PRMI ASC - first pass | I tried implementing a basic PRMI ASC using
the POP QPD as a sensor. The POP22
buildup RMS is reduced by a factor of a few. |
|
14975
|
Thu Oct 17 12:34:51 2019 |
gautam | Update | General | Daytime wishlist | Some ideas that would help increase the
locking duty-cycle in the short term.
Seismometer investigation |
 |
14974
|
Thu Oct 17 11:19:28 2019 |
gautam | Update | LSC | Locking activity last night |
Tuning the MICH-->PRM
output matrix element
Locked
the PRMI with the carrier field resonant |
 |
14973
|
Wed Oct 16 11:42:17 2019 |
gautam | Update | LSC | Poor separation of PRCL/MICH in 3f signals | Summary:
There is poor separation
of the PRCL and MICH length error signals |
|
14972
|
Tue Oct 15 17:22:26 2019 |
gautam | Update | General | Workstation computers back on UPS | Batteries + power cables replaced, and
computers back on UPS from today ~3pm.
|
|
14971
|
Tue Oct 15 17:19:38 2019 |
Koji | Update | General | Wednesday cleaning work | [Liz, Gautam, Chub, Jordan, Koji]
We removed a significant
amount of e-waste from the lab. |
|
14970
|
Mon Oct 14 17:32:28 2019 |
Koji | Update | CDS | Portal Elog entry for the recent CM servo board tests | Updated Circuit Diagram and photos:
https://dcc.ligo.org/D1500308-v2
- (1) and (6) of the diagram: |
|
14969
|
Mon Oct 14 17:24:28 2019 |
gautam | Update | General | Workstation computers taken off UPS (temporarily) | The UPS is now incessantly beeping. I cannot
handle this constant sound so I shut down
all the control room workstations and moved |
|
14968
|
Mon Oct 14 16:34:42 2019 |
Koji | Update | CDS | CM servo board testing | Input referred offsets on the IN1/IN2 were
tested with different gain settings. The
two inputs were plugged by the 50 ohm terminators. |
  |
14967
|
Mon Oct 14 16:25:03 2019 |
Koji | Update | CDS | CM servo board testing | The output stage (and AO GAIN stage) of
the MC board was modelled. The transfer function
was measured with the injection from EXC |
|
14966
|
Mon Oct 14 16:19:30 2019 |
Koji | Update | CDS | CM servo board testing | For the CM board modeling purpose, the
transfer function from TESTA2 to TESTB2 was
needed. (Attachment 1) |
|
14965
|
Mon Oct 14 16:06:28 2019 |
Koji | Update | CDS | CM servo board testing | CM Board Slow out (digital length control)
path transfer function / pole-zero filter
pair (79Hz/1.6kHz) transfer function |
|
14964
|
Thu Oct 10 23:36:02 2019 |
Koji | Update | General | Wednesday cleaning work | [Jon, Yehonathan, Gautam, Aaron,
Shruti, Koji]
We get together on Wednesday afternoon |
  |
14963
|
Thu Oct 10 22:11:53 2019 |
gautam | Update | LSC | Trans QPD checkout |
I removed the flip-mount that was
installed on the EY in-air table for the
mode-spectroscopy project (see |
 |
14962
|
Thu Oct 10 01:12:56 2019 |
gautam | Update | LSC | Locking studies | Summary:
ALS control of arms in
the CARM/DARM basis seems pretty robust - |
|
14961
|
Wed Oct 9 22:02:58 2019 |
gautam | Update | LSC | REFL55 whitening issue | This
problem has re-surfaced. Is this indicative
of some problem with the on-board VGA? Even |
|
14960
|
Wed Oct 9 18:15:26 2019 |
gautam | Update | LSC | PRMI 3f locking | After making sure the beams were hitting
the 3f photodiodes on the "AP"
table, I was able to lock the PRMI with the |
|
14959
|
Wed Oct 9 12:15:05 2019 |
rana | Update | Electronics | WFS head RF measurements | It would be good if you and Shruti can
look at how to change the parameters in Zero
so as to do a fit to the measured data. Usually, |
|
14958
|
Wed Oct 9 09:37:28 2019 |
aaron | Update | IOO | WFS loop measurements | I installed nds2 again, this time successfully
with
|
|
14957
|
Tue Oct 8 20:39:42 2019 |
aaron | Update | IOO | WFS loop measurements | I installed nds2 on donatello with
yum, but still can't import nds2. |
|
14956
|
Tue Oct 8 20:23:03 2019 |
gautam | Update | CDS | c1iscaux testing | Looking at the old latch.st code, looks
like this is just a heartbeat signal to indicate
the code is alive. I'll implement this. |
|
14955
|
Tue Oct 8 18:42:39 2019 |
Koji | Update | CDS | CM servo board testing | The boost filters of the CM servo
board were tested. Their ZPK models were
made. |
|
14954
|
Tue Oct 8 18:35:09 2019 |
gautam | Update | LSC | Locking prep | In preparation for some locking work tonight,
I did the following at the POP in air table
with the PRMI locked on carrier: |
|
14953
|
Tue Oct 8 17:59:29 2019 |
Koji | Update | CDS | CM servo board testing (portal) | == Test Status ==
[done]
Whitening gain switching test |
6x |
14952
|
Tue Oct 8 16:54:56 2019 |
rana | Update | IOO | IMC locking not working after this work | I think this offset setting thing is not
so good. People do this every few years,
but putting offsets in servos means that |
|
14951
|
Tue Oct 8 16:00:06 2019 |
aaron | Update | Electronics | WFS head RF measurements | I simulated this
circuit with zero, but haven't gotten
the results to match the measurements above. |
 |
14950
|
Tue Oct 8 10:29:19 2019 |
gautam | Update | IOO | MC Transmission scan | Summary:
There is ~ 7% variation
in the power seen by the MC2 trans QPD, depending |
  |
14949
|
Tue Oct 8 08:08:18 2019 |
gautam | Update | PEM | PEM BLRMS anomaly | Yesterday, Koji and I noticed (from the
wall StripTool traces) that the vertex seismometer
RMS between 0.1-0.3 Hz in the X-direction |
|
14948
|
Tue Oct 8 03:32:42 2019 |
Koji | Update | CDS | CM servo board testing | [Koji]
The logic chips 74ALS573
were replaced. And now the gain sliders are |
7x |
14947
|
Tue Oct 8 03:19:14 2019 |
Koji | Update | CDS | Final incarnation of latch.py | Now with the CM board tested with the signal
injected, it turned out that the latch logic
was flipped. As the default state locked |
|
14946
|
Mon Oct 7 19:50:33 2019 |
gautam | Update | IOO | IMC locking not working after this work | See trend. This is NOT symptomatic of some
frozen slow machine - if I disable the WFS
servo inputs, the lock holds just fine. |
 |
14945
|
Mon Oct 7 14:51:20 2019 |
aaron | Update | Electronics | WFS head RF measurements | Mon Oct 7 14:51:53 2019. I closed the PSL
shutter to measure the WFS head responsivity.
I made a thru calibration as in |
|
14944
|
Sun Oct 6 15:23:27 2019 |
gautam | Update | ALS | Arm control using error signals achieved | Summary:
I |
  |
14943
|
Sat Oct 5 21:26:34 2019 |
gautam | Update | ALS | Y-end green alignment tweaked | Summary:
I improved the alignment of the
green beam into the Y arm cavity. |
 |
14942
|
Sat Oct 5 00:03:21 2019 |
Koji | Update | CDS | c1iscaux testing | [Gautam, Koji]
Input gain part of the
CM servo board D1500308 |
   |
14941
|
Fri Oct 4 22:22:03 2019 |
gautam | Update | CDS | Final incarnation of latch.py | [KA, GV]
This elog is meant to be a summary
of some of the many subtleties |
|
14940
|
Fri Oct 4 14:25:59 2019 |
aaron | Update | General | Make the Jenne-laser setup fiber-coupled | Summary:
The fiber-coupled
PD seems to have a factor of ~1.5 difference
in responsivity compared to the free-space |
  |
14939
|
Fri Oct 4 01:57:09 2019 |
Koji | Update | CDS | c1iscaux testing | The AA filter for ASDC was fixed.
== Test Status ==
[done] |
   |
14938
|
Fri Oct 4 00:32:24 2019 |
gautam | Update | ALS | More locking updates | Summary:
I managed to achieve a few transitions
of control of the XARM length using the ALS |
 |
14937
|
Fri Oct 4 00:30:31 2019 |
gautam | Update | General | Make the Jenne-laser setup fiber-coupled | I think the metric of interest here is
the consistency of the AC transimpedance
of the proposed new "Reference PD" |
|
14936
|
Thu Oct 3 23:15:39 2019 |
Koji | Update | General | Make the Jenne-laser setup fiber-coupled | The 1GHz PD has a bit more flat response,
but the laser and the driving network have
more frequency dependence as you saw. |
|
14935
|
Thu Oct 3 21:50:22 2019 |
rana | Update | Computers | rossa revival | Got the network to work again just by unplugging
the power cord and letting it sit for awhile.
But corrupted OS by trying to install Nvidia |
|
14934
|
Thu Oct 3 21:05:04 2019 |
aaron | Update | General | Make the Jenne-laser setup fiber-coupled | I measured the RF response of the fiber-coupled
NewFocus 1611, calibrating out the cable
delay. The laser current was set to 20.0 |
|
14933
|
Thu Oct 3 19:40:18 2019 |
gautam | Update | LSC | POX/POY imbalance | Summary:
There is an imbalance between
the POX and POY detector outputs reported |
|
14932
|
Thu Oct 3 14:54:33 2019 |
Koji | Update | General | Make the Jenne-laser setup fiber-coupled | I'm afraid that the RF modualtion of
the laser is nonlinear and the electrical
and optical resoponse is dependent on the |
|
14931
|
Thu Oct 3 14:32:37 2019 |
rana | Update | General | Make the Jenne-laser setup fiber-coupled | I'm
curious to see if we really need the 1611,
or if we can calibrate the diode laser vs. |
|
14930
|
Thu Oct 3 12:08:47 2019 |
gautam | Update | General | Make the Jenne-laser setup fiber-coupled | I propose the following re-organization
of the PDFR measurement breadboard. We have
all the parts on hand, just needs ~30mins |
 |
14929
|
Thu Oct 3 11:38:35 2019 |
aaron | Update | IOO | WFS measurements | I set up the spectrum analyzer to make
the WFS head RF transfer function measurement
(V/W) on WFS1. I placed the Jenne laser on |
|