[Jenne Louis Matt]
The change in the filters used by calibration created a 10% calibration error. Louis is trying to fix this but in an effort to have a way to revert to the previous filters without losing lock Jenne came up with a cdsutils way to revert back. Essentially it toggles off the new filters ('H1:OMC-DCPD_A0 FM10 H1:OMC-DCPD_B0') FM10
and steps the demod phase ('H1:OMC-LSC_PHASEROT')
in steps of 1 degree, 77 times, with a 0.065 sec delay (77steps/5seconds) between each step. The filter toggles have a 5 second ramp time, which informs the step delay in the cdsutils step, and the 77 degrees is the difference from the old demod phase and the new. Hopefully this avoids a lockloss in the event we are to revert, but may not. *fingers crossed*
Here is the command:
cdsutils switch H1:OMC-DCPD_A0 FM10 OFF; cdsutils switch H1:OMC-DCPD_B0 FM10 OFF; cdsutils step H1:OMC-LSC_PHASEROT 1,77 -s 0.065
UPDATE:
It worked :) anti-alias filters off and OMC-LSC phaserot returned to nominal