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Next: THE PE 3220 Up: POWERING UP THE Previous: SUMMARY FOR EXPERTS

INSTRUMENT ROTATOR

  1. The rotator position angle is conventionally zero for most instruments but 270. for Wide Field Camera.
  2. It is usually difficult to rotate an instrument because of the cable ties put on by the daylight staff. If you envisage rotating the instrument please ask them or your support astronomer to arrange sufficiently long free leads to rotate as far as you want; usually +/- 90 degrees. It is wise to rehearse this manouevre in daylight before attempting at night.
  3. First zenith park the telescope. None of our instruments is exactly balanced in rotation and may swing out of control when the telescope isn't in the zenith.
  4. Go to the observing floor and undo the rotation clamp.
  5. Rotate to the desired angle using the push buttons. Watch the cables carefully throughout because even if they are long enough they may still get tangled.
  6. Reclamp
  7. Return to console and continue observing. The control computer can read the rotator position angle so no further action on the observer's part is needed.




Tue Aug 5 05:37:08 MET DST 1997