User's Guide to the Lick 36" Refracting Telescope

Slit (shutter)
Lens Cover
Position Indicators
Tangent Arm
Access Ports
Control Desk
Observing Hits
Trouble Shooting

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Dome General

The Dome section covers opening and closing of the slit, rotation, parking, temperature management, and light control.

The historic Lick 36" Refractor is a completely manual telescope. The dome is also manual. To open and close the shutter/slit one actuates a switch on the desk console. It is labeled open and close. There are limit switches so that one only need to move the switch in its desired position and the shutter will open or close and stop the motor at the appropriate position.

The dome does not track and needs to be moved manually to keep it aligned with the telescope. One moves it clockwise or counter clockwise via one of the two sets of switches. The first set is on the desk (Figure 1). The second set is on the paddle (Figure 2). The desk control is a switch that when actuated will move the dome until the switch is returned to the neutral position. The controls on the telescope paddle will only move the dome when continuous pressure is exerted on the button.

The park position of the dome is such that the shutter is pointed to the east. There is an orange line painted on the moving and fixed part of the dome (see Figures 3 & 4). Parking the dome within 0.25 meters of the line is sufficient. It actually is desirable to not park it exactly in the same spot as we have seen the electrical contacts in the orange high voltage ring/wheel interface degrade causing the dome to only move in one direction initially.

There isn't any active temperature control for the dome but there are several things that one should do to manage temperature. First is to open the dome shutter prior to moving the floor up. The action of moving up the floor aids in pushing out warm air in the dome. It may also be advisable to open the windows prior to moving the floor. One should take measures to keep main building air from rushing in to the dome floor as it is usually much warmer and will be turbulent. This is principally accomplished by ensuring both sets of doors are kept closed.

Dome lighting is controlled by switches on the desk console and by switches on the east side of the lower door. There is also a dark screen for the lower door that should be lowered during public nights.

Figure 1: Dome Control Panel on Desk Console

Figure 2: Dome Control Paddle

Figure 3: Dome Stow Position

Figure 4: Dome Stow Marks