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Entry  Mon Aug 10 15:24:17 2009, rob, Summary, PSL, MZ bad brokenMZpzt.png
    Reply  Mon Aug 10 15:56:12 2009, rob, Summary, PSL, MZ bad redux badMZtrans.png
Message ID: 1875     Entry time: Mon Aug 10 15:56:12 2009     In reply to: 1874
Author: rob 
Type: Summary 
Category: PSL 
Subject: MZ bad redux 


I think the MZ pzt is broken/failing.  I'm not sure how else to explain this behavior.


The first bit of the time series is a triangle wave into the DC offset (output) field, over approximately the whole range (0-250V).   You can see the fringe visbility is quite small.  The triangle wave is stopped, and I then maxed out the offset slider to get to the "high" power point from the triangle wave sweep. Then for a little while with the PZT is held still, and the power still increases.  The MZ is then locked, and you can see the PZT voltage stay about the same but the power continues to rise over the next ~10 minutes or so.




This plot answers the previous question, and raises a new one--what the heck is MZTRANSPD?  I'd guess the pins are unconnected--it's just floating, and somehow picking up the MZ_PZT signal.



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