[paco, ian]

After the new 1Y0 rack was placed near the 1Y1 rack by Chub and Anchal, today we worked on the 1Y1 rack. We removed some rails from spaces ~ 25 - 30. We then drilled a pair of ~ 10-32 thru-holes on some L-shaped bars to help support the c1sus2 machine weight. The hole spacing was set to 60 cm; this number is not a constant across all racks. Then, we mounted c1sus2. While doing this, Paco's knee clicked some of the video MUX box buttons (29 and 8 at least). We then opened the rack's side door to investigate the DC power strips on it before removing stuff. We did power off the DC33 supplies on there. No connections were made to allow us to keep building this rack.

When coming back to the control room, we noticed 3/4 video feed (analog) for the Test masses had gone down... why?

Next steps:

• Remove sorensen (x5) power supplies from top of 1Y1 .. what are they actually powering???
• Make more bars to support heavy IO exp and acromag chassis.
• Make all connections (neat).

Update Tue Nov 2 18:52:39 2021

• After turning Sorensens back up, the ETM/ITM video feed was restored. I will need to hunt the power lines carefully before removing these.