User's Guide to the Crossley Telescope

Table of Contents

Ground Level
Dome and Platform
Head Rotation
Dec Tangent Arm
Position Indicators
Mirror Cover
Dome Slit
Access Ports
RA Drive Preload
Operating Limits
New Telescope Drive

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Dome Layout and Facilities: Ground Level

As you come in the inside door, there are two light switches on the inside of the door jamb to your left, higher up than usual. The bottom one is for red lights at the ground level; the other is for a white light on the north pier at mezzanine level. (There is another switch for the white light on the pier itself, just a few inches below the light.)

The office is used by many observers. Please assist by keeping it neat and clean. All lunch remains must be deposited in the covered garbage can in the entrance way; otherwise rodents and insects will find their way into the dome. If you open any windows, be sure to close and lock them when you leave the dome!

There is a bathroom on the east side of the dome and water in the darkroom in the southeast. DO NOT under any circumstances change the settings of the heat exchanger in the darkroom.

Outlets for the telephone are located in the office just above the desk, beside the main stairs to the mezzanine, and on the telescope itself to the right of the dec clamp wheel.

Beside the mezzanine stairs near the phone jack are two switches. One is for the ground level red lights and the other controls a small red bulb at the top of the mezzanine stairs. Because the construction of this dome presents unique orientation problems, the mezzanine stairs present a dangerous hazard and it is suggested that this small red light be left on whenever possible, at least until you are very familiar with the dome. Notice the two alternate sets of stairs on either side of the south polar axle. These are for use when the mezzanine stairs are covered.

Under the stairs by the office door is an air compressor for the dec preload. It comes on automatically and unpredictably whenever the pressure drops below a certain level, so expect to the startled by it occasionally. It's pretty loud.

Figure 1: Ground Floor Layout