ID |
Date |
Author |
Type |
Category |
Subject |
Text |
 |
11047
|
Wed Feb 18 17:51:40 2015 |
ericq | Update | LSC | ALS Fool impulse response | Koji raised a good question about the step
response I wrote about. Namely, if the UGF
of the ALS servo is around 100Hz, we would |
|
11046
|
Wed Feb 18 01:58:51 2015 |
ericq | Update | LSC | ALS Fool single arm performance | I'm playing around with the lastest
ALS fool feedforward on the Yarm, and I like
what I'm seeing. |
   |
11045
|
Tue Feb 17 19:49:51 2015 |
Koji | Update | LSC | Delay line un-installed again | The modulation setting was reverted.
Demod phase for REFL11/33/55/165 and
AS55 were reverted to the previous numbers |
|
11044
|
Tue Feb 17 16:44:04 2015 |
Koji | Update | LSC | Delay line installed again | For tonight's experiment, I re-installed
the delay line cable and changed the attenuation
to 10dB for the 55MHz modulation. |
|
11043
|
Tue Feb 17 16:36:08 2015 |
Jenne | Update | LSC | ALS fool math | Here is an updated cartoon, with the ALS
sensor explicitly shown as the beatbox times
the closed loop response of the phase tracker |
 |
11042
|
Tue Feb 17 04:04:32 2015 |
Jenne | Update | LSC | ALS fool math | I re-did the Mathematica notebook according
to the most current diagram (note to daytime
self: attach .nb file!!!), and found that |
 |
11041
|
Tue Feb 17 00:24:47 2015 |
rana, jenne | Update | LSC | ALS Fool filter updated for more cancellation | Today
we measured the TFs again and then updated
the filter in the POY -> ALS FF path so |
 |
11040
|
Mon Feb 16 21:52:51 2015 |
rana | HowTo | Treasure | big Dataviewer windows | Following this
entry, I have made the same change in
the controls account on rossa: |
|
11039
|
Mon Feb 16 15:08:26 2015 |
Jenne | Update | LSC | ALS fool measured decoupling TF | Dang it, yes. You're right. I
should have caught that.
Since Dcpl and Srefl are both zero |
|
11038
|
Mon Feb 16 03:10:42 2015 |
Koji | Update | LSC | ALS fool measured decoupling TF | Wonkey shape: Looks like a loop supression.
Your http://nodus.ligo.caltech.edu:8080/40m/11016
also suggests it too, doesn't it? |
|
11037
|
Mon Feb 16 02:49:57 2015 |
Jenne | Update | LSC | ALS fool measured decoupling TF | I have measured very, very carefully the
transfer function from pushing on
MC2 to the Yarm ALS beatnote. |
 |
11036
|
Mon Feb 16 01:45:12 2015 |
Koji | Summary | LSC | modulation depth analysis | Based on the measured modulation profiles,
the depth of each modulation was estimated.
Least square sum minimization of the |
 |
11035
|
Mon Feb 16 00:08:44 2015 |
Koji | Summary | LSC | [ELOG LIST] 3f modulation cancellation | This KTP crystal has the maximum allowed
RF power of 10W (=32Vpk) and V_pi = 230V.
This corresponds to the maximum allowed |
|
11034
|
Sun Feb 15 20:55:48 2015 |
rana | Summary | LSC | [ELOG LIST] 3f modulation cancellation | I wonder if DRMI can be locked on 3f using
this lower 55 MHz modulation depth. It seems
that PRMI should be unaffected, but that |
|
11033
|
Sun Feb 15 16:20:44 2015 |
Koji | Summary | LSC | [ELOG LIST] 3f modulation cancellation | Summary
of the ELOGS
3f
modulation cancellation theory |
|
11032
|
Sat Feb 14 22:14:02 2015 |
Koji | Summary | LSC | [HOW TO] 3f modulation cancellation | When I finished my measurements, the modulation
setup was reverted to the conventional one.
If someone wants to use the 3f cancellation |
  |
11031
|
Sat Feb 14 20:37:51 2015 |
Koji | Summary | LSC | 3f modulation cancellation | Experimental
results
- PD response [Attachment |
   |
11030
|
Sat Feb 14 20:20:24 2015 |
Jenne | Update | LSC | ALS fool cartoon | The ALS fool scheme is now diagrammed up
in OmniGraffle, including its new official
icon. The mathematica notebook has |
 |
11029
|
Sat Feb 14 19:54:04 2015 |
Koji | Summary | LSC | 3f modulation cancellation | Optical
Setup
[Attachment 1] |
  |
11028
|
Sat Feb 14 00:48:13 2015 |
Koji | Update | LSC | 3f modulation cancellation | [SUCCESS]
The 3f sideband cancellation seemed worked
nicely. |
|
11027
|
Sat Feb 14 00:42:02 2015 |
Koji | Update | General | RF amplifier for ALS | The RF analyzer was returned to the control
room. There are two beat notes from X/Y confirmed.
I locked the arms and aligned them |
|
11026
|
Fri Feb 13 19:41:13 2015 |
ericq | Update | General | RF amplifier for ALS | As Koji found one of the spare channels
of the ALS/FOL RF amplifier box nonfunctional
yesterday, I pulled it out to fix it. I found |
|
11025
|
Fri Feb 13 18:56:44 2015 |
rana | Update | Electronics | Second QPD Whitening Switch enabled | Depends on the plots of the whitening I
guess; if its low freq sat, then we lower
the light level with ND filters. If its happening |
|
11024
|
Fri Feb 13 17:07:51 2015 |
Jenne | Update | Electronics | Second QPD Whitening Switch enabled | I first updated the DCC branches for the
Xend and Yend to reflect the as-built situation
from December 2014, and then I updated the |
|
11023
|
Fri Feb 13 14:59:13 2015 |
ericq | Update | Electronics | Second QPD Whitening Switch enabled | Went to zero CARM offset on ALS; transmission
QPDs are still saturating :(
Maybe we need to switch off all |
|
11022
|
Fri Feb 13 14:27:30 2015 |
ericq | Update | Electronics | Second QPD Whitening Switch enabled | I have re-enabled the second whitening
stage switching on each quadrant of each
end's QPD whitening board, to try and |
|
11021
|
Fri Feb 13 03:44:56 2015 |
Jenne | Update | LSC | Held using ALS for a while at "0" CARM offset with PRMI | [Jenne, Rana]
We wanted to jump right in and
see if we were ready to try the new "ALS |
 |
11020
|
Fri Feb 13 03:28:34 2015 |
rana | Update | LSC | New Locking Paradigm - Loop-gebra | Not
so fast!
In the drawing,
the FF path should actually be summed in |
|
11019
|
Thu Feb 12 23:47:45 2015 |
Koji | Update | LSC | 3f modulation cancellation | - I built another beat setup on the PSL
table at the South East side of the table.
- The main beam is not touched, no |
|
11018
|
Thu Feb 12 23:40:12 2015 |
rana | Update | IOO | Bounce / Roll stopband filters added to MC ASC filter banks | |
|
11017
|
Thu Feb 12 22:28:16 2015 |
Jenne | Update | LSC | New Locking Paradigm - LSC model changes, screens modified | I have modified the LSC trigger matrix
screen, as well as the LSC overview screen,
to reflect the modifications to the model |
|
11016
|
Thu Feb 12 19:18:49 2015 |
Jenne | Update | LSC | New Locking Paradigm - Loop-gebra | EDIT, JCD, 17Feb2015: Updated loop
diagram and calculation: http://131.215.115.52:8080/40m/11043
Okay, Koji and I talked |
|
11015
|
Thu Feb 12 15:21:37 2015 |
ericq | Update | Computer Scripts / Programs | netgpib updates | I've fixed the gpib scripts for the
SR785 and AG4395A to output data in the same
format as expected by older scripts when |
|
11014
|
Thu Feb 12 12:23:21 2015 |
manasa | Update | General | Waking up the PDFR measurement system | [EricG, Manasa]
We woke up the PDFR measurement
setup that has been sleeping since summer. |
|
11013
|
Thu Feb 12 12:16:04 2015 |
manasa | Update | General | Fiber shielding | [Steve, Manasa]
The fibers around the PSL table
were shielded to avoid any tampering. |
|
11012
|
Thu Feb 12 11:59:58 2015 |
Koji | Update | LSC | New Locking Paradigm - Loop-gebra | The goals are:
- When the REFL path is
dead (e.g. S_REFL = 0), the system goes back |
|
11011
|
Thu Feb 12 11:14:29 2015 |
Jenne | Update | LSC | New Locking Paradigm - Loop-gebra | I have calculated the response of this
new 2.5 loop system.
The first attachment is my block |
 |
11010
|
Thu Feb 12 03:43:54 2015 |
ericq | Update | LSC | 3F PRMI at zero ALS CARM | I have been able to recover the ability
to sit at zero CARM offset while the PRMI
is locked on RELF33 and CARM/DARM are on |
|
11009
|
Thu Feb 12 01:43:09 2015 |
rana | Update | LSC | New Locking Paradigm - LSC model changes | With the |
|
11008
|
Thu Feb 12 01:00:18 2015 |
rana | Update | LSC | RFPD spectra | The nonlinearity in the LSC detection chain
(cf T050268)
comes from the |
|
11007
|
Wed Feb 11 22:13:44 2015 |
Jenne | Update | LSC | New Locking Paradigm - LSC model changes | In order to try out the new locking scheme
tonight, I have modified the LSC model.
Screens have not yet been made. |
|
11006
|
Wed Feb 11 18:44:53 2015 |
manasa | Update | General | Optical fiber module | I have moved the optical fiber
module for FOL to the PSL table. It is setup
on the optical table right now for testing. |
|
11005
|
Wed Feb 11 18:11:46 2015 |
Koji | Summary | LSC | 3f modulation cancellation | 33MHz sidebands can be elliminated by careful
choice of the modulation depths and the relative
phase between the modulation signals. |
|
11004
|
Wed Feb 11 18:07:42 2015 |
ericq | Update | LSC | RFPD spectra | After some discussion with Koji, I've
asked Steve to order some SBP-30+ bandpass
filters as a quick and cheap way |
|
11003
|
Wed Feb 11 17:31:11 2015 |
ericq | Update | LSC | RFPD spectra | For future reference, I've taken spectra
of our various RFPDs while the PRMI was sideband
locked on REFL33, using a 20dB RF coupler |
   |
11002
|
Wed Feb 11 16:49:41 2015 |
rana | Update | elog | ELOGD restarted | No elog
response from outside and no elogd process
|
|
11001
|
Wed Feb 11 04:08:53 2015 |
Jenne | Update | LSC | New Locking Paradigm? | [Rana, Jenne]
While meditating over what to do
about the fact that we can't seem to |
|
11000
|
Wed Feb 11 03:41:12 2015 |
Koji | Update | LSC | PRC error signal RF spectra | As the measurements have been done under
feedback control, the lower RF peak height
does not necessary mean |
|
10999
|
Wed Feb 11 02:42:05 2015 |
Jenne | Update | LSC | PRC error signal RF spectra | Since we're having trouble keeping
the PRC locked as we reduce the CARM offset,
and we saw that the POP22 power is significantly |
 |
10998
|
Wed Feb 11 00:07:54 2015 |
rana | Update | LSC | Lock Loss plot | Here is a lock loss from around 11 PM tonight.
Might be due to poor PRC signals. |
 |