Numerous mechanisms on DEIMOS are operated by air pressure
cylinders. If these mechanisms have been in one position for a
long time (8 hours or more) they occasionally may fail to move.
Most often this affects the grating clamps, but it can also
happen with the front hatch or other mechanisms. Altough
stages are unlikely to get stuck at night, it's worthwhile
knowing how to fix the problem.
- Go to the back of DEIMOS (side away from telescope).
- Locate the facility air line coming into the instrument
(see Figure 1 below).
- Disconnect the air line by pulling down on the collar and
then removing the line from the socket.
- Wait 10 seconds.
- Reconnect the air line.
Figure 1. Location of the DEIMOS facility air line.