40m
QIL
Cryo_Lab
CTN
SUS_Lab
TCS_Lab
OMC_Lab
CRIME_Lab
FEA
ENG_Labs
OptContFac
Mariner
WBEEShop
|
40m Log |
Not logged in |
 |
|
Tue Feb 2 18:35:47 2016, gautam, Update, Green Locking, Lightwave NPRO moved from PSL table to SP table
|
Tue Feb 2 18:54:02 2016, Koji, Update, Green Locking, Lightwave NPRO moved from PSL table to SP table
|
Wed Feb 3 23:23:47 2016, gautam, Update, Green Locking, Lightwave NPRO moved from PSL table to SP table 
|
Thu Feb 4 09:16:46 2016, Koji, Update, Green Locking, Lightwave NPRO moved from PSL table to SP table
|
Fri Feb 5 00:23:01 2016, gautam, Update, Green Locking, Lightwave NPRO moved from PSL table to SP table   
|
Fri Feb 5 16:50:24 2016, gautam, Update, Green Locking, First pass at mode-matching   
|
Mon Feb 8 15:36:37 2016, gautam, Update, Green Locking, Alternative mode-matching scheme
|
Tue Feb 9 04:37:10 2016, ericq, Update, Green Locking, Laser swap initiated
|
Tue Feb 9 11:49:47 2016, gautam, Update, Green Locking, Laser swap initiated
|
Tue Feb 9 19:15:36 2016, gautam, Update, Green Locking, Laser swap - updates 
|
Wed Feb 10 17:57:15 2016, gautam, Update, Green Locking, Laser swap - updates
|
Fri Feb 12 17:05:40 2016, gautam, Update, Green Locking, Laser swap - green light recovered but no flashes in the arm
|
Fri Feb 12 19:07:52 2016, Koji, Update, Green Locking, Laser swap - green light recovered but no flashes in the arm
|
Fri Feb 19 00:42:19 2016, gautam, Update, Green Locking, Laser swap - beam ellipticity from laser?  
|
Mon Feb 22 13:56:52 2016, gautam, Update, Green Locking, Laser swap -reflected beam from ETM aligned
|
Tue Feb 23 23:01:16 2016, gautam, Update, Green Locking, Laser swap - Green PDH locking 
|
Wed Feb 24 19:29:13 2016, gautam, Update, Green Locking, Laser swap - Green PDH locked
|
Fri Feb 26 01:52:44 2016, gautam, Update, Green Locking, Laser swap - Green PDH OLTF
|
Mon Feb 29 17:17:26 2016, gautam, Update, Green Locking, Laser swap - still no green beatnote
|
Wed Mar 2 17:42:19 2016, gautam, Update, Green Locking, Laser swap - some progress
|
Thu Mar 3 01:25:50 2016, gautam, Update, Green Locking, Laser swap - 2 IR + 1 green beatnotes found
|
Fri Mar 4 01:11:41 2016, gautam, Update, Green Locking, Laser swap - both green beatnotes found
|
Sat Mar 5 23:31:01 2016, gautam, Update, Green Locking, Laser swap - some updates    
|
Mon Mar 7 23:51:36 2016, gautam, Update, Green Locking, Laser swap - some improvement   
|
Tue Mar 8 18:22:20 2016, rana, Update, Green Locking, Laser swap - some improvement
|
|
Message ID: 12006
Entry time: Tue Feb 23 23:01:16 2016
In reply to: 12002
Reply to this: 12009
|
Author: |
gautam |
Type: |
Update |
Category: |
Green Locking |
Subject: |
Laser swap - Green PDH locking |
|
|
Given that we were seeing green flashes in the arms, I tried to see if I could get the green locked to the arm in a nice mode. For a start, I tried hooking up the PDH box and LO using the same settings as was being used previously. However, this did not work. I suppose we will have to do the whole AM/PM measurement for the Lightwave as well before we can determine what would be a suitable frequency for the LO. The AM measurement was relatively straightforward, I just repeated the same steps as detailed here. The two attachments show the AM response (one from 10kHz to 5MHz, the other for a narrower range of 100kHz to 1MHz, both with an excitation amplitude of 0dBm). To see if I could guess some sweetspot for operation, I tried setting the LO frequency to the two marked notch frequencies but was unsuccessful in getting the PDH lock going. At the moment, the alignment for the optics that picks off the IR after the doubler and routes it to the fiber are ccompletely misaligned, I will align these and do the PM measurement tomorrow and then we should conclusively be able to say what the appropriate frequency is to actuate on the PZT.
Unrelated to this work: the KEPCO high voltage power supply that drives the green steering mirror PZTs was switched off - I suppose this has been the case since the power outage last week. I turned it back on and reset it to the nominal settings: Vout = 100V, and Imax_out = 10mA, the driver board is currently drawing ~7mA which I judged to be consistent with the values labelled on the unit. |
|
|
|
|