PZT1, the one with Koji's custom mid-HV driver (#5447), is getting degraded.
The movable range in the pitch direction became narrower than what it used to be (maybe a factor of 3 estimated by looking at the beam spots).
I think we should raise the priority level of the active TTs for the next vent.
I have been having a feeling that the PZT1 response is getting smaller since the end of the last year, but now I am confident
because I could see the difference between the movable ranges of Yaw and Pitch, and they used to have approximately the same amount of the movable ranges.
Right now this is not a serious issue as the beam pointing determined by the MC alignment is so good that the Pitch range doesn't rail.
I won't be surprised if it becomes completely immovable in 3 month. |