Elenna, Keita, Oli

Input alignment:

Today Elenna and I finished fine-tuning the alignment into the BHSS, so now our beams pass through both sets of irises on the alignment tooling plate, so they should be well aligned to go into the OMCs nicely.

OMCA in cradle:

We also opened up what is going to be OMCA (SN 103) and placed it in its cradle. We followed the installation instructions and placed the OMC 1mm away from the three installed horizontal stops, but then we noticed that lining the short end up against the side horizontal stop led to the OMC overhanging the cradle on that side by a few mm. We're not sure if these end stops are also supposed to be further inwards than 1mm (the instructions just specify that they (the horizontal stops) will be touching the OMC 1mm in), but if we placed the other end stop in with the way that the OMC is currently positioned, that other stop would have to screw in at least 3 or 4 mm to meet up with the OMC. We will add photos of this tomorrow.

Installing DCPDs onto OMCA:

Keita and Elenna (who was chained to the optics table via grounding strap) very carefully trimmed the DCPD wires for D1-20 and C1-12 and placed them in the DCPD mounts for DCPD A (which is what we think TRANS is), and DCPD B (which is what we think REFL is), respectively. Faceplate SN 10 was installed onto DCPD A, and faceplate SN 06 was installed onto DCPD B to hold the PDs in place. It was very hard to get the length of the DCPD pins right, and getting the faceplates on and secured. There seems to be a small gap in between the faceplates and the DCPD housing (pic1, pic2), but LLO has the same thing happening so it seems okay. 

Checking pins

After we used a multimeter to check that the case pins followed D220027. According to D220027 the case pins should be going to pins 6 and 9, but we found that they went to what we thought were pins 1 and 4 when we were looking at the prongs. Later we found that the DB9 pin layout is read the other way, so that means that it was actually pins 2 and 5. This still doesn't line up with D220027, but looking at the schematic for the cable D2300119, it turns out that the wires for the Cases for the two DCPDs are shifted so that the Cases do actually go to pin 2 and pin 5, so they're wired correctly! It's just that D220027 is wired up incorrectly and appearantly the cable pins are read with the prongs facing away from you for some reason.

OMCA is looking pretty good so far! (pic3, pic4)

Summary of installed serial numbers:

OMCA (SN 103)

• DCPD A (TRANS)
  • DCPD: 1D-20
  • Housing: SN 10
• DCPD B (REFL)
  • DCPD: 1C-12
  • Housing: SN 06