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Entry  Wed Aug 27 18:03:47 2014, ericq, Update, Green Locking, uPDH Box Checkup uPDH_X.JPGuPDH_Y.JPGupdhTFs.pdfupdhNoises.pdfuPDH_Aug27.zip
    Reply  Thu Aug 28 17:34:20 2014, ericq, Update, Green Locking, uPDH Box Checkup TEK00006.PNG
       Reply  Fri Aug 29 17:28:07 2014, rana, Update, Green Locking, uPDH Box Checkup 
          Reply  Fri Aug 29 23:53:35 2014, ericq, Update, Green Locking, uPDH Box Checkup 
             Reply  Tue Sep 2 20:02:06 2014, ericq, Update, Green Locking, uPDH Box Checkup 
       Reply  Wed Sep 3 00:17:22 2014, rana, Update, Green Locking, uPDH Box Checkup 
          Reply  Wed Sep 3 20:38:40 2014, ericq, Update, Green Locking, uPDH Box Checkup 
             Reply  Fri Sep 5 04:07:44 2014, ericq, Update, Green Locking, X end uPDH Box Replaced 
                Reply  Fri Sep 5 16:13:00 2014, ericq, Update, Green Locking, new X Green PDH measurements 6x
                   Reply  Sat Sep 6 01:48:54 2014, rana, Update, Green Locking, new X Green PDH measurements 
                      Reply  Sat Sep 6 14:49:12 2014, ericq, Update, Green Locking, new X Green PDH measurements xGComparison.pdfxGspectra.pdf
                         Reply  Sun Sep 7 17:06:38 2014, rana, Update, Green Locking, new X Green PDH measurements 
                         Reply  Mon Sep 8 14:14:13 2014, Jenne, Update, Green Locking, new Y Green PDH measurements 6x
Message ID: 10433     Entry time: Wed Aug 27 18:03:47 2014     Reply to this: 10437
Author: ericq 
Type: Update 
Category: Green Locking 
Subject: uPDH Box Checkup 

 Quick post of plots and data; I'll fill in more detail tonight. 

TL;DR: I pulled both green PDH boxes and made LISO models, compared TFs and noise levels. 


Pictures of X and Y boards, respectively

uPDH_X.JPGuPDH_Y.JPG

 


TF comparison to LISO. (Normalized to coincide at 1Hz)

updhTFs.pdf

 


Noise comparison to LISO

updhNoises.pdf

 


To Do:

  • Figure out why TFs were made differently. Check PM response curves of PZTs to see if they are fine, or need tweaking.
  • Make boosts useful. Both are currently integrators with corners under 10Hz, which is already pretty suppressed. 
  • I just noticed that the X board is missing C25, which should be a 1uF cap on the positive power pin of the primary TF stage opamp. This should be inserted. 

All data, EAGLE schematics, LISO source and plots in the attached zip. 

 

Attachment 5: uPDH_Aug27.zip  6.386 MB
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