Changing beam splitters :

1. telnet termsrv2 5015
2. split 1
3. Go up to the dome, and take the new beam splitter. They are stored in a wooden box (labelled "Beam Splitters"), normally in one of the AOB cabinets on the 5th floor. Do not ever think of using the 85/10 beamsplitter, which has an horrendous optical ghost...
4. Remove the cover of the beam-splitter mechanism
5. Unscrew the old beam splitter, and replace with the new one. Correct position is with label on the outside.
6. Put the cover back.
7. Put the old splitter back in the box.
8. split 2
9. That's it...