Summary:  Less than +/-10% Change in DARM Actuation Coefficient from June 28 to present.

On July 14th, we reported in LHO alog #19163 that the DARM actuation after the vent had not changed by more than 10% from its ER7 value. Responding to a request from LeoP, we made a similar plot for the period from June 28 until now.  

The attached plot has 60s-long FFT data plotted in blue and 30-point running averages of the blue data plotted in red. The data includes all times when the Guardian State Vector value was more than 501 (DC Readout).  

The data were generated using the low frequency calibration lines (~ 35 Hz) which had low SNR before July 22nd. We increases the SNR of our calibration lines to about 100, informed by an  ER7 calibration line study, and reported in alog #19792 and the attached comments. Here we have also accounted for the fact that the response function of DARM, C/(1+G), is frequency dependent (calibration lines being few Hz apart) using the DARM refrence model for ER7.