TELESCOPE USE
1. Quick Tips
•
Viewfinder Alignment with Main Telescope:
When first attached to the
telescope, the viewfinder and main optical tube are not aligned.
Therefore, it is not possible to locate objects in the main telescope using
the viewfinder. Procedures for aligning the viewfinder and main telescope
are discussed below.
•
Declination and R.A. Controls:
With the ETX sitting on a table, as
shown in Fig. 1, the Declination controls are used to move the telescope
vertically (up and down). The Right Ascension controls are used to move
the telescope horizontally (side to side). Move Knobs Slowly: When
making adjustments in R.A., Dec, or focusing, turn the controls slowly.
Moving the controls too quickly may result in losing the object or passing
the focus point. Moving the ETX Astro Telescope: The ETX optical tube is
not designed to rotate a full 360° through its fork arms. The viewfinder
bracket contacts one of the fork arms at a point just past the 90° position
of the optical tube in the fork arms. Do not attempt to force the telescope
tube past this point or damage to the viewfinder bracket will result.
•
A Note on Indoor Viewing:
While casual, low-power observations may
be made with the telescope through an open or closed window, the best
observing is always done outdoors. Temperature differences between
inside and outside air and/or the low quality of most home window glass
can cause blurred images through the telescope. Do not expect high-
resolution imaging under these conditions.
2. Telescope Controls
An important array of controls facilitates operation of the ETX telescope. Be sure
to acquaint yourself with all of these controls before attempting observations
through the telescope.
R.A. Lock (11, Fig. 1):
With the ETX sitting on a table as shown in Fig. 1, this control locks the telescope from
moving horizontally. Turning the R.A. Lock counterclockwise unlocks the telescope horizontally, enabling the
telescope to be freely moved by hand in a horizontal direction. Turning the R.A. Lock clockwise locks the telescope
in horizontal position.
R.A. Slow-Motion Control (10, Fig. 1):
With the R.A. Lock in the unlocked position, the R.A. Slow-Motion Control
may be used for manual slewing of the telescope in a horizontal direction.
The R.A. Slow-Motion Control should
never be turned when the R.A. Lock is in the locked position; damage to the internal gears may otherwise
result.
The R.A. Lock must be engaged for the motor drive to track on an object.
Dec Lock (21, Fig. 11):
With the ETX sitting on a table as shown in Fig. 1, this control locks the telescope from
moving vertically. (The definition of "Dec," or "Declination," is explained further below.) Turning the Dec Lock
clockwise (to a firm feel only) locks the telescope in the vertical position. Turning the Dec Lock about one full turn
counterclockwise permits manual motion of the telescope in the vertical position.
Dec Slow-Motion Control (16, Fig. 1):
With the Dec Lock in the locked position, the Dec Slow-Moton Control may
be used for fine motions of the telescope in a vertical direction. The Dec Slow-Motion Control has a fixed travel
length. At some point after turning the Dec Slow-Motion Control continuously in the same direction, the control will
become difficult to turn.
Do not attempt to turn the Dec Slow-Motion Control past this point or damage to the
internal mechanism will result.
Instead, back-off the Dec Slow-Motion Control by turning the control about 50
turns in the opposite direction. Unlock the Dec Lock and move the telescope manually to center the object; then
resume use of the Dec Slow-Motion Control.
Fig. 3: Bottom Surface of the Drive Base.
(1) Attachment Screws; (2) Upper Hole;
(3) Center Hole; (4) Lower Hole; (5) Base
Plate; (6) Drive Base; (7) North-South
Switch; (8) On-Off Switch.
Fig. 4: Showing three AA-size batteries
installed inside the drive base.
Summary of Contents for ETX Series
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