40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  PSL  Not logged in ELOG logo
Entry  Tue Mar 27 23:32:22 2012, frank, tara, DailyProgress, Seismic, Seismic coupling from curtain frame to beat IMG_0681.jpg
    Reply  Thu Mar 29 00:46:33 2012, frank, tara, DailyProgress, Seismic, Seismic coupling from curtain frame to beat IMG_0687.JPGIMG_0688.JPG
       Reply  Fri Mar 30 00:50:43 2012, frank, tara, DailyProgress, Seismic, Seismic coupling from curtain frame to beat compare.png
          Reply  Tue Apr 3 20:56:10 2012, frank, tara, DailyProgress, Seismic, Seismic coupling from curtain frame to beat beat_2012_04_03.png
             Reply  Wed Apr 4 18:57:11 2012, rana, DailyProgress, Seismic, Seismic coupling from curtain frame to beat 
                Reply  Sun Apr 8 23:35:05 2012, tara, DailyProgress, Seismic, Seismic coupling from curtain frame to beat beat_ciplot.pngbeat_ciplot.png
                   Reply  Mon Apr 9 23:05:44 2012, tara, DailyProgress, Seismic, Seismic coupling from curtain frame to beat brownian_mult.m.zip
Message ID: 894     Entry time: Fri Mar 30 00:50:43 2012     In reply to: 891     Reply to this: 896
Author: frank, tara 
Type: DailyProgress 
Category: Seismic 
Subject: Seismic coupling from curtain frame to beat 

The coupling from frame motion to beat signal is now significantly reduced after we fixed the cable wiring .

 

      The plot below shows the acceleration measured on the frame and the corresponding beat signals. I did not calibrate the signal since this is just a qualitative check.  I tried to excite the frame so that the signals from the frame motion were comparable (blue and cyan). After we fixed the cables wiring, the beat signal (pink) are less sensitive to the frame vibration than before (red).

      Note that the set up were similar in both measurements. The input range for PLL was 5kHz, with gain 200.

compare.png

 

I have not measured the beat signal after we fixed the cable yet. It will be interesting to see if the beat has been improved or not.

ELOG V3.1.3-