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Entry  Thu Nov 19 12:00:04 2009, Zach, Misc, SUS, bandpass filter BPF_bode_11_18_09.png
    Reply  Fri Nov 20 06:18:51 2009, rana, Misc, SUS, bandpass filter 
Message ID: 125     Entry time: Thu Nov 19 12:00:04 2009     Reply to this: 126
Author: Zach 
Type: Misc 
Category: SUS 
Subject: bandpass filter 

 Attached is the transfer function for the bandpass filter I built for the AOSEM readout. The schematic is primitively outlined below. The corner frequencies are what they should be (HP: 100 mHz, LP: 1 kHz)

The Johnson noise for the 1 k resistor is roughly 4 nV/rt(Hz). Frank says that it doesn't make sense to use much lower than 1 k if I'm putting it into an SR785.

 

 

           10 uF                  1 k

      -------| |-------------/\/\/\/\/\/------------------

                        | |

        < |

         160 k  >        _|_  160 nF

        <        ---

        > |

        | |

                V                 V

 

Attachment 1: BPF_bode_11_18_09.png  48 kB  | Hide | Hide all
BPF_bode_11_18_09.png
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