jeffrey.kissel@LIGO.ORG - posted 16:53, Thursday 27 April 2023 - last comment - 16:55, Thursday 27 April 2023(69117)
Modified All CAL-CS Calibration DEMOD I and Q Low-Pass filters from 0.1 Hz to 0.025 Hz Corner Frequency
E. Goetz, J. Kissel As Evan and I were continuing to debug the PCAL calibration lines processed for the first time against DELTAL_EXTERNAL as a live measure of the calibration's systematic error, we were distracted by the noise in the magnitude and phase of the "final answer." As such, I've converted all DEMOD_I and DEMOD_Q banks, which filter out the 1w and 2w components of the demodulated PCAL, DARM_ERR, and DELTAL_EXTERNAL signals at each calibration line frequency to have a 0.1 Hz low pass in FM1 and a 0.025 Hz low pass in FM2. The first attachment shows the reduction in noise as a I switch from "all banks using 0.1 Hz LPs" (on the left of the plot) and eventually "all banks using 0.025 Hz LPs." The second attachment shows that I've SDF accepted these values. The third attachment shows an example on of these demods (in this case the "LINE5" PCAL line demod).
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Since there was 60 of these filter banks, and I want to make the swithc quickly, I "wrote" this "quick" unsophisticated command line to switch each the filters each "LINE" in one go. Posted here just in case we need switch back, or change to a different corner frequency low pass some time in the future.
export LINE=LINE8;z switch H1:CAL-CS_TDEP_PCAL_${LINE}_PCAL_DEMOD_I FM1 OFF; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_PCAL_DEMOD_Q FM1 OFF; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_PCAL_DEMOD_I FM2 ON; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_PCAL_DEMOD_Q FM2 ON; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_ERR_DEMOD_I FM1 OFF; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_ERR_DEMOD_Q FM1 OFF; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_ERR_DEMOD_I FM2 ON; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_ERR_DEMOD_Q FM2 ON; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_EXT_DEMOD_I FM1 OFF; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_EXT_DEMOD_Q FM1 OFF; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_EXT_DEMOD_I FM2 ON; z switch H1:CAL-CS_TDEP_PCAL_${LINE}_EXT_DEMOD_Q FM2 ON;