Alexa, Pablo, Keita, Stefan

We noticed that H1:ALS-Y_VCO_TUNEMON and H1:ALS-Y_VCO_FREQUENCY were only reacting to half the range of the drive from the common mode board (H1:ALS-Y_REFL_SERVO_FASTMON). We thus swapped the EX VCO ( D0900605 , S1200562 ) with a H2 spare ( S1200566 ). This fixed the issue.

Next we noticed that the PDH signal doesn't bring the arm power to a maximum.
With a H1:ALS-Y_REFL_SERVO_IN1GAIN of -13dB, and an H1:ALS-Y_REFL_SERVO_COMOFS of -4.75V we get the maximum build-up, about 1750 counts of H1:ALS-C_DIFF_A_LF_OUT_DQ. With a misaligned ITM Keita and Alexa verified that it is not an RFAM effect.

We still see transients in the arm build-up.