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Entry  Mon Apr 18 14:52:47 2022, Ian MacMillan, Summary, SEI, Seismic Study of Buildings and Caltech Campus 7x
    Reply  Thu Apr 21 17:32:35 2022, Ian MacMillan, Summary, SEI, Seismic Study of Buildings and Caltech Campus IMG_1820.jpgScreen_Shot_2022-04-21_at_5.52.51_PM.png
Message ID: 16798     Entry time: Thu Apr 21 17:32:35 2022     In reply to: 16783
Author: Ian MacMillan 
Type: Summary 
Category: SEI 
Subject: Seismic Study of Buildings and Caltech Campus 

[Rana, Ian]

We built a power supply for the accelerometer shown in Attachment 1 based on the diagram shown in the Wilcoxon manual and shown in attachment 2. We used a 9V power supply and a capacitor value of 680uF. We did not use a constant current diode. 

When hooked up to an oscilloscope we saw vibrations from hitting our hands on the table but we did not see the same amplitude in the negative and positive directions. For example, when I held the accelerometer and moved it down you would see a dip then a peak as the accelerometer accelerated down then accelerated up when I stopped the down word movement. But weirdly when I did the opposite (moved the accelerometer up the same dip then a peak appeared. This is a little concerning because it should be the opposite. it should be a peak then a dip. This in addition to the seemingly decreased sensitivity in one direction make me think that the accelerometer is broken.

I labeled the box with "might be broken" before I returned it to the cryo lab.

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Attachment 2: Screen_Shot_2022-04-21_at_5.52.51_PM.png  788 kB  Uploaded Thu Apr 21 18:52:56 2022  | Hide | Hide all
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