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Entry  Thu Jul 26 13:10:51 2012, janosch, Update, LSC, modelled ringdown Ringdown.png
    Reply  Thu Jul 26 15:43:03 2012, rana, Update, LSC, modelled ringdown 
Message ID: 7039     Entry time: Thu Jul 26 15:43:03 2012     In reply to: 7038
Author: rana 
Type: Update 
Category: LSC 
Subject: modelled ringdown 

You cannot use the digital system for this. You hook up a scope to the transmitted light as well as the incoming light (after the MC, perhaps at IP_POS). Then you acquire the data from both places simultaneously using an ethernet equipped scope. The step response of the PDs used for this has to be calibrated separately.

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