40m
QIL
Cryo_Lab
CTN
SUS_Lab
TCS_Lab
OMC_Lab
CRIME_Lab
FEA
ENG_Labs
OptContFac
Mariner
WBEEShop
|
40m Log |
Not logged in |
 |
|
Mon Jul 4 10:30:37 2016, ericq, Update, General, Preliminary vent plans
|
Tue Jul 5 17:14:02 2016, ericq, Update, General, Vent progress 
|
Tue Jul 5 19:10:41 2016, rana, Update, General, Vent progress
|
Tue Jul 5 21:51:35 2016, ericq, Update, General, Vent progress
|
Tue Jul 5 23:38:42 2016, gautam, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Wed Jul 6 22:58:01 2016, gautam, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Thu Jul 7 00:25:07 2016, ericq, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Thu Jul 7 10:49:03 2016, gautam, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Fri Jul 8 11:35:45 2016, gautam, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Fri Jul 8 11:48:09 2016, Koji, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Fri Jul 8 14:03:26 2016, ericq, Update, General, ETMX removed from suspension
|
Fri Jul 8 16:33:26 2016, ericq, Update, General, ETMX removed from suspension
|
Fri Jul 8 20:44:09 2016, Koji, Update, General, ETMX removed from suspension 6x
|
Sun Jul 10 15:38:01 2016, ericq, Update, General, ETMX in guiderod/standoff gluing fixture 6x
|
Tue Jul 12 16:08:00 2016, ericq, Update, General, ETMX ruby guided gluing
|
Wed Jul 13 21:13:51 2016, Koji, Update, General, ETMX guide rod gluing / ETMY Magnet gluing 13x
|
Thu Jul 14 22:29:57 2016, ericq , Update, General, ETMX guide rod gluing / ETMY Magnet gluing
|
Fri Jul 15 16:23:51 2016, ericq , Update, General, Gluing setbacks 
|
Tue Jul 19 16:39:29 2016, Lydia, Update, General, ETMX magnet gluing/guiderod excess glue removed 
|
Wed Jul 20 13:58:55 2016, Steve, Update, SUS, SUS damping out of vac chamber   
|
Thu Jul 21 17:01:59 2016, ericq, Update, General, ETMX magnet gluing/guiderod excess glue removed
|
Fri Jul 22 23:03:23 2016, gautam, Update, General, ETMX suspension - progress    
|
Sun Jul 24 03:43:56 2016, ericq, Update, General, Magnet positioning
|
Mon Jul 25 13:01:49 2016, ericq, Update, General, ETMX suspension - progress    
|
Mon Jul 25 13:47:19 2016, rana, Update, General, ETMX suspension - progress
|
Mon Jul 25 17:01:54 2016, Steve, Update, SUS, ETMX suspension - progress
|
Mon Jul 25 20:37:46 2016, gautam, Update, General, ETMX suspension - Side OSEM test
|
Tue Jul 26 18:07:57 2016, gautam, Update, General, ETMX suspension - Further OSEM Tests
|
Thu Jul 28 03:22:28 2016, ericq, Update, General, ETMX magnets re-reglued
|
Thu Jul 28 13:49:44 2016, gautam, Update, General, ETMX magnets re-reglued 
|
Thu Jul 28 17:48:17 2016, gautam, Update, General, ETMY LR magnet broke off
|
Thu Jul 28 22:43:03 2016, rana, Update, General, ETMY UL magnet broke off
|
Wed Aug 3 10:52:03 2016, Steve, Update, General, ETMY soaking dish  
|
Fri Jul 29 03:32:30 2016, ericq, Update, General, ETMX suspended once more
|
Fri Jul 29 13:17:34 2016, Koji, Update, General, Oven
|
Thu Jul 14 01:00:33 2016, Koji, Update, General, ETMX ruby guided gluing
|
Thu Jul 28 16:43:01 2016, Lydia, Update, General, ETMX aluminium standoff groove condition   
|
Fri Jul 8 21:22:38 2016, gautam, Update, General, Vent progress - ETMX SUS Coil driver electronics investigation
|
Wed Jul 6 09:34:26 2016, Steve, Update, General, PRM sensing voltage LR
|
Wed Jul 6 19:36:45 2016, Koji, Update, General, SUS Vmon  
|
Thu Jul 7 15:23:39 2016, ericq, Update, General, SUS Vmon
|
Thu Jul 7 16:05:55 2016, Koji, Update, General, SUS Vmon
|
Thu Jul 7 17:12:50 2016, Johannes, Update, General, Vent progress   
|
Tue Jul 12 23:51:16 2016, Johannes, Update, General, Vent progress - ETMY inspection 
|
Wed Jul 13 00:38:25 2016, Johannes, Update, General, Vent progress - ETMY attempted repositioning
|
Tue Jul 19 13:21:42 2016, Johannes, Update, General, Vent progress - ETMY attempted repositioning
|
Sun Jul 10 17:33:00 2016, ericq, Update, General, Vent progress
|
Mon Jul 11 15:13:22 2016, gautam, Update, General, Vent progress: in-date First Contact procured
|
|
Message ID: 12255
Entry time: Wed Jul 6 19:36:45 2016
In reply to: 12246
Reply to this: 12268
|
Author: |
Koji |
Type: |
Update |
Category: |
General |
Subject: |
SUS Vmon |
|
|
I wanted to know what this Vmon exactly is. D010001 is telling us that the Vmon channels are HPFed with fc=30Hz (Attachment 1). Is this true?
I checked the quiscent noise spectrum of the ITMX UL coil output (C1:SUS-ITMX_ULCOIL_OUT ) and the corresponding VMON (C1:SUS-ITMX_ULVmon ). (Attachment 2 Ref curves). I did not find any good coherence. So the nominal quiscent Vmon output is carrying no useful information.
Question: How much do we need to excite the coil output in order to see any meaningful signal?
As I excite the ITMX UL coil (C1:SUS-ITMX_ULCOIL_EXC ) with uniform noise of 100-300 counts below 0.3Hz, I eventually could see the increase of the power spectrum and the coherence (Attachment 2). Below 0.1 Hz the coherence was ~1 and the transfer function was measured to be -75dB and flat. But wait, why is the transfer function flat?
In fact, if I inject broadband noise to the coil, I could increase the coil output and Vmon at the same time without gaining the coherence. (Attachment 3). After some more investigation, I suspect that this HPF is diabled (= bypassed) and aliasing of the high freq signal is causing the noise in Vmon.
In order to check this hypothesis, we need to visit the board. |
|
|
|
|
|
|