40m
QIL
Cryo_Lab
CTN
SUS_Lab
TCS_Lab
OMC_Lab
CRIME_Lab
FEA
ENG_Labs
OptContFac
Mariner
WBEEShop
|
40m Log |
Not logged in |
 |
|
Thu Jan 4 12:46:27 2018, gautam, Update, ALS, Fiber ALS assay 
|
Thu Jan 11 14:22:40 2018, gautam, Update, ALS, Fiber ALS assay
|
Thu Jan 11 20:51:20 2018, gautam, Update, ALS, Fiber ALS assay
|
Tue Jan 16 21:50:53 2018, gautam, Update, ALS, Fiber ALS assay
|
Thu Jan 18 00:35:00 2018, gautam, Update, ALS, Fiber ALS assay 
|
Fri Jan 19 11:34:21 2018, gautam, Update, ALS, Fiber ALS assay
|
Fri Jan 19 23:04:11 2018, gautam, Update, ALS, Fiber ALS assay
|
Wed Jan 24 00:33:31 2018, gautam, Update, ALS, Fiber ALS assay
|
Wed Jan 24 10:45:14 2018, gautam, Update, ALS, Fiber ALS assay
|
Thu Jan 25 23:59:14 2018, gautam, Update, ALS, Fiber ALS assay
|
Fri Jan 26 20:03:09 2018, gautam, Update, ALS, Fiber ALS assay
|
Wed Jan 31 15:45:22 2018, gautam, Update, ALS, Fiber ALS assay
|
Wed Jan 31 16:29:42 2018, gautam, Update, ALS, Modulation depths 
|
Wed Jan 31 16:33:53 2018, gautam, Update, ALS, ALS electronics at LSC rack
|
Wed Jan 31 22:32:11 2018, gautam, Update, ALS, ALS signal chain + power budget 
|
Thu Feb 1 01:24:56 2018, gautam, Update, ALS, D0902745 revamp underway
|
Fri Feb 2 00:26:34 2018, gautam, Update, ALS, D0902745 revamp underway
|
Fri Feb 2 13:16:55 2018, gautam, Update, ALS, ALS signals whitening switching 
|
Mon Feb 5 14:11:01 2018, gautam, Update, ALS, Huge harmonics in ALS channels 
|
Mon Feb 5 22:57:28 2018, gautam, Update, ALS, Huge harmonics in ALS channels
|
Tue Feb 6 11:13:26 2018, gautam, Update, ALS, Possible source of ground loop identified
|
Tue Feb 6 22:55:51 2018, gautam, Update, ALS, Possible source of ground loop identified
|
Thu Feb 8 00:33:20 2018, gautam, Update, ALS, D990694 characterization / THD measurement plan
|
Thu Feb 8 01:27:16 2018, Koji, Update, ALS, D990694 characterization / THD measurement plan
|
Fri Feb 9 13:37:44 2018, gautam, Update, ALS, THD measurement trial
|
Thu Feb 8 12:00:09 2018, gautam, Update, ALS, D990694 is NOT differential receiving
|
Thu Feb 8 13:13:14 2018, gautam, Update, ALS, D990694 pulled out  
|
Thu Feb 8 18:10:36 2018, gautam, Update, ALS, D990694 pulled out
|
Wed Feb 7 15:51:15 2018, gautam, Update, ALS, D0902745 revamp complete
|
Fri Feb 16 01:34:40 2018, gautam, Update, ALS, D0902745 in-situ testing 
|
Tue Feb 20 23:08:27 2018, gautam, Update, ALS, D0902745 in-situ testing
|
Thu Feb 22 00:09:11 2018, gautam, Update, ALS, D0902745 in-situ testing  
|
Sun Feb 25 00:03:12 2018, gautam, Update, ALS, Daughter board prototyping    
|
Mon Feb 26 20:55:56 2018, rana, Update, ALS, Daughter board prototyping
|
Tue Feb 27 21:10:45 2018, gautam, Update, ALS, Daughter board testing  
|
Wed Feb 28 19:13:25 2018, gautam, Update, ALS, ADC test for differential receiving in c1lsc
|
Fri Mar 2 01:45:06 2018, gautam, Update, ALS, new look ALS electronics
|
Mon Mar 5 17:27:34 2018, gautam, Update, ALS, new look ALS electronics - characterization
|
Thu Mar 8 00:40:25 2018, gautam, Update, ALS, new look ALS electronics - characterization
|
Thu Mar 8 19:38:37 2018, gautam, Update, ALS, digital unwhitening of daughter board
|
Thu Mar 8 23:50:27 2018, gautam, Update, ALS, First look at new ALS electronics
|
Fri Mar 9 01:07:01 2018, gautam, Update, ALS, First look at new ALS electronics
|
Mon Mar 12 22:08:31 2018, gautam, Update, ALS, Noisy POX
|
Mon Mar 12 23:57:31 2018, gautam, Update, ALS, Noisy POX 
|
Mon Mar 19 15:02:29 2018, gautam, Update, ALS, Noisy MC sensing
|
Thu Feb 1 15:31:12 2018, gautam, Update, ALS, ALS signal chain + power budget
|
Wed Feb 7 10:16:26 2018, gautam, Update, ALS, ALS signal chain + power budget
|
Thu Jan 25 13:18:41 2018, gautam, Update, ALS, Fiber ALS assay
|
|
Message ID: 13658
Entry time: Tue Feb 27 21:10:45 2018
In reply to: 13657
Reply to this: 13661
13663
|
Author: |
gautam |
Type: |
Update |
Category: |
ALS |
Subject: |
Daughter board testing |
|
|
I thought a little bit about the next steps in testing the daughter board. The idea is to install this into the existing 1U chassis and tap the differential output from the FET Mixers as inputs to the daughter board. Looking at the D0902745 schematic, I think the best way to do this is to simply remove L3, L4, C10, C11, C15 and C16. I will then use the pads for L3 and L4 to pipe the differential output of the FET mixer to the differential input of the daughter board.
The daughter board takes care of whitening the ALS signal.
Then we need to pipe the differential output of the daughter board into the differential input of a differential receiving AA board. Koji and Johannes surveyed the available stockpile from the WB workshop. The best option seems to be to use the available v5 of D070081 and install 4 of them into a 1U chassis unit (also available from WB EE shop). The v5s can be upgraded to v6 by replacing the set of input and output buffer OpAmps with AD8622, as per the revision history notes. Koji ordered 100pcs of these today.
The input to the proposed 1U chassis housing these 8 AA boards (each with 8 channels) is a DB9 connector. The aLIGO demod board chassis that we use to demodulate the ALS signals has a nice DB25 output connector that supplies all the differential I and Q demodulated signals. But since we will install a daughter board, we will hae to hack together some connector solution anyways. I propose using a DB9 connector to pipe the outputs of the daughter board to the inputs of the AA board. Space is tight in the LSC rack, but I think we have space for a 1U chassis (see Attachment #3).
Finally - how to interface the AA board with the ADC? Koji and I discussed options, and seems like the least painful way will be to install a new ADC in the c1lsc expansion chassis in 1Y3. I checked the computer hardware cabinet and there seems to be 1 spare general standards 16bit ADC in there (see Attachment #1). Its health/providence is unknown. But Koji and I will test it after the meeting tomorrow. I also have another ADC card that Jamie and I removed from c1ioo sometime ago. I have labelled it as "GPIO0 LED RED", though I don't remember exactly what the problem was and can't find any elog about it. Incidentally, there are also 2 spare DAC cards available in the cabinet, although their health/rpovidence too is unknown. There are sufficient free slots in the c1lsc expansion chassis (see Attachment #2 though we will need a LIGO ADC adaptor card). Then we can just change the input ADC channels for the ALS signals in the c1lsc model.
In the short term, while the hardware for this plan is being put together, I can test the uncalibrated noise performance of the demod + daughter board combo (uncalibrated because I will make a measurement of voltage noise with an SR785 as opposed to frequency noise). A second daughter board will also need to be assembled - I'm just going to do it on another prototyping board as figuring out how to use Altium will probably take me longer. There is also the matter of fine tuning the polarization axes alignment of the input to the EX fiber coupler. |
|
|
|
|
|
|