40m
QIL
Cryo_Lab
CTN
SUS_Lab
TCS_Lab
OMC_Lab
CRIME_Lab
FEA
ENG_Labs
OptContFac
Mariner
WBEEShop
|
40m Log |
Not logged in |
 |
|
Wed Apr 13 00:56:07 2016, gautam, Update, endtable upgrade, X endtable repopulation
|
Wed Apr 13 11:00:28 2016, Steve, Update, endtable upgrade, X endtable repopulation
|
Wed Apr 13 18:25:07 2016, gautam, Update, endtable upgrade, Lightwave health check
|
Fri Apr 15 18:38:12 2016, gautam, Update, endtable upgrade, Lightwave health check - NO IMPROVEMENT
|
Tue Apr 19 18:37:29 2016, gautam, Update, endtable upgrade, Laser swap + optical layout
|
Thu Apr 21 14:25:52 2016, gautam, Update, endtable upgrade, Green light recovered  
|
Tue Apr 26 15:22:35 2016, Steve, Update, endtable upgrade, Cleaning ETMX vacuum dirty window 
|
Tue Apr 26 23:19:42 2016, gautam, Update, endtable upgrade, Green aligned to arm - high order mode flashes seen 
|
Thu Apr 28 00:41:08 2016, gautam, Update, endtable upgrade, more progress - Transmon PD installed
|
Fri Apr 29 00:55:46 2016, gautam, Update, endtable upgrade, green PDH locked to Xarm
|
Mon May 2 19:14:18 2016, gautam, Update, endtable upgrade, Optical layout almost complete
|
Thu May 5 03:05:37 2016, gautam, Update, endtable upgrade, ALS status update  
|
Thu May 5 04:05:03 2016, ericq, Update, LSC, Aux X PDH checks 
|
Thu May 5 14:03:52 2016, ericq, Update, LSC, Further Aux X PDH tweaks
|
Thu May 5 14:05:01 2016, rana, Update, endtable upgrade, ALS status update
|
Thu May 5 21:28:44 2016, gautam, Update, endtable upgrade, Innolight PZT capacitance
|
Thu May 19 16:29:20 2016, Steve, Update, endtable upgrade, Optical layout almost complete 
|
Fri Sep 30 19:53:07 2016, gautam, Update, endtable upgrade, X end IR pickoff fiber coupled
|
Wed Oct 5 16:28:10 2016, gautam, Update, endtable upgrade, EX laser power monitor PD installed
|
Wed Apr 27 15:04:47 2016, Steve, Update, endtable upgrade, Cleaning ETMX vacuum dirty window
|
Fri Apr 29 16:05:23 2016, gautam, Update, endtable upgrade, Cleaning ETMX vacuum dirty window
|
|
Message ID: 12108
Entry time: Thu May 5 14:05:01 2016
In reply to: 12105
|
Author: |
rana |
Type: |
Update |
Category: |
endtable upgrade |
Subject: |
ALS status update |
|
|
All seems very fishy. Its not good to put attenuators and filters in nilly-willy.
- Once the post-PD bandpass has been designed and constructed, you should be able to use whatever PD gain setting gives you the best SNR. There's no need to use more PD gain than necessary; it just reduces the PD bandwidth. What is the input referred current noise of the PD at the different gain settings?
- The open loop mixer output *should* be very large. It should be reduced to mV only when the loop is closed.
- The better way to estimate the modulation depth is to lock the arm on red as usual and then scan the EX laser and look at the green transmission. The FSR is 3.7 MHz, so the SBs should show up well in a narrow scan around the carrier.
- I guess its going to be tough to impedance match the splitter box to the NPRO PZT, since its impedance is all over the place at 200-300 kHz, but you could put a 50 Ohm in-line terminator in there somewhere?
- The Bode plot seems to indicate that we could easily get a 10 kHz UGF and then switch on a Boost. Is the remote Boost switch disabled or always ON? I am suspicious of the plot and think that the coarse trace is probably missing some sharp resonances which will sneakily bite you.
|