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Entry  Tue Mar 11 15:19:45 2014, Jenne, Update, Electronics, High gain Trans PD electronics change IMG_1309.JPG
    Reply  Tue Mar 11 19:07:24 2014, ericq, Update, Electronics, High gain Trans PD electronics change SQRTINVwhitening.pdfsqrtinvWhitening.zip
    Reply  Thu Apr 17 16:04:40 2014, Jenne, Update, Electronics, High gain Trans PD electronics change 
Message ID: 9720     Entry time: Tue Mar 11 19:07:24 2014     In reply to: 9716
Author: ericq 
Type: Update 
Category: Electronics 
Subject: High gain Trans PD electronics change 

Speaking of the whitening board, I had neglected to post details showing the the whitening was at least having a positive effect on the transmon QPD noise. So, here is a spectrum showing the effects that the whitening stages have on a QPD dark noise measurement like I did in ELOG 9660, at a simulated transmission level of 40 counts. 

The first whitening stages gives us a full 20dB of noise reduction, while the second stage brings us down to either the dark noise of the QPD or the noise of the whitening board. We should figure out which it is, and fix up the board if necessary. 

SQRTINVwhitening.pdf

The DTT xml file is attached in a zip, if anyone wants it.

Attachment 2: sqrtinvWhitening.zip  345 kB  Uploaded Tue Mar 11 20:08:17 2014
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