Tear-down

 Since the Fabry-Perot is classified as a ``private'' Palomar instrument, the user must also disassemble and pack up the instrument after using it. Because the Palomar crew begins their workday early, i.e., 8:00 a.m., this usually means that the instrument must be disassembled before going to bed after the last night of the run. Fortunately, this task is much simpler than setting up the instrument; it can be readily accomplished in about an hour. If for some reason you are unable to disassemble the instrument before going to bed, you should at least power down the etalon controller and remove the etalon cables. Then contact the Palomar crew to notify them that you will be returning later to pack up the instrument.

As expected, the tear-down procedure is essentially the setup procedure in reverse order. To summarize the primary steps:

1.

Run the fabry r command to release computer control of the etalon controller. This will allow you to use the front-panel controls on the CS-100 (see Figure 11).

2.

Turn off the power to the CCD and the etalon controller. Be sure to switch the operate/balance switch to balance first. If you are at the 200-inch telescope, turn off the power to the shutter controller as well. Close the valve on the nitrogen bottle, and then the regulator itself.

3.

Unplug all cables. This includes the CCD cables, the etalon controller cables, and the nitrogen hose. If you are at the 200-inch telescope, the shutter cables and computer control coax cables should also be removed, as well as the short-haul modems. Pack all of the cables in the appropriate box.

4.

If you are at the 200-inch telescope, pack up the shutter controller and return the variable power supply to the electronics lab.

5.

Remove the CCD dewar from the instrument by loosening the clamps on the dewar plate. Replace the lid on the chip side of the dewar to protect the CCD window and place the dewar on a workbench. The Palomar crew will take care of the CCD from this point.

6.

Unbolt the instrument from the telescope. Following the setup instructions in reverse, remove and pack the cable boot box, focus plate, focus arm, camera lens, shutter (if used), and etalon. Take care to replace the covers on the etalon and securely shut it within its case. The extension ring must also be removed in order for the instrument tube to fit in its case. Finally, replace the camera and dewar plates on the tube, fasten the cardboard covers on either end and over the cable boot hole, for protection, and pack the instrument tube in its fiberglass case.

7.

Pack up the etalon controller. If you are at the 200-inch telescope, this will also involve removing the controller from the Cassegrain rack and replacing it in its original cover.

8.

Remove all filters from the filter wheel and restore them to their original locations. If you are at the 200-inch telescope, be sure to restore the filters to their original holders, and pack the special filter holders with the Fabry-Perot equipment.

9.

Pack up the calibration lamp. If you are at the 200-inch telescope, you may have to wait until the Palomar crew can retrieve the lamp from prime focus.

10.

Remove the regulator from the nitrogen bottle, and pack it with the Fabry-Perot equipment. Do not attempt to remove the nitrogen bottle from the Cassegrain cage at the 200-inch telescope; the Palomar crew will take care of this.

11.

Tightly close all of the equipment cases. Check the telescope to be sure that you have not forgotten any equipment.

If you are observing at the 60-inch telescope, you should store the equipment cases in the ground-level storage room, across from the elevator. If you are at the 200-inch telescope, stack the cases out of the way on the observing floor; the Palomar crew will take them back to the 60-inch storage room.

Be sure to retrieve the backup tapes of your data before departing the mountain!