Aso, Miyo, Fujii, with help of MPC Ito, Shimizu,


= PR2 =
-- We started a repairing work of a broken cable (one soldering part was off at micro-Dsub connector for IM-OSEM-V3), as reported in klog#6535.
-- What we did was:
  -- to remove a bellows between PR2 and BS with MPC people.
  -- to open the side flange and the top flange.
  -- to disattach IM-OSEM-V2 cable inside the chamber and then attach the new one, which had same length (2.0 m)
  -- we checked the cable tension status and then concluded it looked okay by eyes.
-- Afetr this, we measured mechanical transfer function without any controls and found that:
  -- The resonant frequencies of the peaks were mostly same as before this repairing (Fig1, the red one was measured after this replacement, the magenta one was emasured before this work).
  -- IM-V TF was improved, it became more reasonable. (Fig3)

== Other notes ==
  1. It was also found that the Q-factor became quite small when the height of the BF-keystone was at lower position:

  -- Actually, the magenta curve in these figures were measured *NOT* at 315, but at around 750 um in K1:VIS-PR2_BF_DAMP_GAS_IN.
  -- Also in the previous tuning klog#6535, we did not complete repairing, and this issue was always there in the Xarm-commissining period.
  -- Thus, it would be good if we use this BF at lower position below/around ~ 700 um in K1:VIS-PR2_BF_DAMP_GAS_IN.

2. After this repairing work, we found that the 2 following signals were missing:
  -- K1:VIS-PR2_BF_LVDTINF_V2
  -- K1:VIS-PR2_BF_LVDTINF_H3
    -- About V2, the coils were connected electrically properly, but sometimes the signal became on/off the medm screen.
    -- About H3, one coil (2-7pin) were connected *NOT* electrically properly, but sometimes the signal became on/off the medm screen.
  -- These cable connection is to be investigated.

== To do next ==
  -- improve the cabling status
  -- to tune the balance of BF and IM so that the optical lever goes back t0 original (start) position.
  -- investigate thte SF-STM status.