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Entry  Thu Feb 18 18:49:21 2010, Dmass, Electronics, Doubling, Bad PD?! 
    Reply  Thu Feb 18 21:16:01 2010, Dmass, Electronics, Doubling, Bad PD?! PDDarkNoise.pdf
       Reply  Fri Feb 19 01:04:35 2010, Dmass, Electronics, Doubling, Bad PD?! 
          Reply  Fri Feb 19 07:54:14 2010, rana, Electronics, Doubling, Bad PD?! 
Message ID: 612     Entry time: Thu Feb 18 21:16:01 2010     In reply to: 610     Reply to this: 613
Author: Dmass 
Type: Electronics 
Category: Doubling 
Subject: Bad PD?! 

Quote:

One of my switchable gain Si detectors appears to have particularly bad noise perfomance.

I compared the dark Voltage noise of my Thorlabs PDs. I am barely below the ADC noise on one of my PDs, and it onlyu gets worse at lower frequencies, so for Beta, on my current setup, the PD noise is limiting me below about 5 Hz.

 

Detector Noise (V/rtHz) @ 10 Hz Gain Setting
Alpha(532) 600 n 47500 V/A
Beta(532) 4 u 47500 V/A
Gamma(1064) 40 n 4750 V/A
Delta(1064) 200  n 4750 V/A

 

 Added a measurement:

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