[Tega, Anchal, Paco]
We started working on SR2 installation. Preliminary work involved
- Removing SR3 from BS chamber. For whatever reason this optic was still installed. It got relocated in the west corner of the ETMX flow bench.
That was pretty much it. After identifying the cabling situation, we proceeded to bring SR2 from the cleanroom. The magnets and wires remained well through their travel.
Connected OSEM one-by-one. Starting from top right to left (PIn1)
1st connector: LL -> UR -> UL
2nd connector: LR -> SD** (we had some trouble here where the first time we made a connection we didn't see any signal, after a brief review of cables, sat amp unit, cables again with Koji, and sat amp again, we found out a connection was not done in the front of the SR2 SatAmp box, after which we saw the sensor signals).
Loosening all OSEMs and taking them out and noting full bright readings:
- SD: 29600 -> 14980
- LR: 21840 -> 10920
- UR: 25900 -> 12950
- LL: 28020 -> 14010
- UL: 25750 -> 12875
After finishing the initial SD osem tuning, we moved onto UL, and then to UR, but we noticed that the UR was not able to drop to its target value of ~13000 counts, even when the OSEM face was < 1 mm from the adapter (see Attachments #1-2). Apart from becoming harder to push in, it became apparent that the dark level (full shadow) is not consistent with ~ 0 counts; is there an offset coming from SatAmp? We quickly checked the OSEM by replacing it in-situ with another working one from the cleanroom batch, but the issue persisted. We decided to stop here, as we suspect the SatAmp box might have some issue.
Photos: https://photos.app.goo.gl/HXzG6mj4oxKTksjZ7 |