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Entry  Mon Dec 27 05:38:56 2021, rana, Update, Control System, cavity locking loop shape 
    Reply  Mon Jan 24 10:24:49 2022, shruti, Update, Control System, cavity locking loop shape OLTF_fit.pdf
       Reply  Wed Jan 26 17:28:53 2022, shruti, Update, Control System, cavity locking loop shape ctrl_pdh_5kHz_Screenshot.pngctrl_pdh_10kHz_Screenshot.pngscope_red.pdffilter_red.pngctrl_pdh_100kHz_Screenshot.png
          Reply  Mon Jan 31 19:03:43 2022, shruti, Update, Control System, cavity locking loop shape - pomona box TF FilterTF.pdfdata_and_analysis.zip
Message ID: 2849     Entry time: Mon Jan 31 19:03:43 2022     In reply to: 2843
Author: shruti 
Type: Update 
Category: Control System 
Subject: cavity locking loop shape - pomona box TF 

[rana, shruti]

Today we measured the transfer function of the pomona box I had made earlier using a tee at the output port and splitting it between a 10kOhm resistor [to simulate the modulation input of the ITC 502 current driver] and the input of the Moku kept at 1 MOhm impedance and DC coupled. The output amplitude was 700 mV with 50 Ohm impedance. for the measurement

I used the script found in labutils to quickly fit the zero and pole to the measured TF. The pole is 45 Hz, and zero at 1.5 kHz, which is more or less what was expected.

Attachment 1: FilterTF.pdf  19 kB  | Hide | Hide all
FilterTF.pdf
Attachment 2: data_and_analysis.zip  13 kB
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