Celestron NexStar 102GT, Instruction Manual

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COMPUTERIZED TELESCOPE
MOTOR SPEED BUTTON
The MOTOR SPEED button allows you to instantly change the speed rate of the motors from high
speed slew rate to precise guiding rate or anywhere in between. Each rate corresponds to a number
on the Hand Controller key pad. The number 9 is the fastest rate (approximately 3.5º per second,
depending on the mount) and is used for slewing between objects and locating alignment stars.
The number 1 on the Hand Control is the slowest rate (half sidereal) and can be used for accurate
centreing of objects in the eyepiece. To change the speed of the motors:
• Press the MOTOR SPEED key on the hand control. The LCD will display the current
motor speed.
• Press the number on the Hand Control that corresponds to the desired speed.
The Hand Control has a “double button” feature that allows you to instantly speed up the motors
without having to choose a speed. To use this feature, simply press the arrow button that corresponds
to the direction that you want to move the telescope. While holding that button down, press the
opposite direction button. This will increase the speed to the maximum slew rate.
When using the up and down direction buttons on the Hand Control, the slower slew rates (6 and lower)
move the motors in the opposite direction than the faster slew rates (7- 9). This is done so that an object
will move in the appropriate direction when looking into the eyepiece (i.e. pressing the up arrow button
will move the star upwards in the field of view of the eyepiece). However, if any of the slower slew rates
(rate 6 and below) are used to centre an object in the StarPointer, you may need to press the opposite
directional button to make the telescope move in the correct direction.
SET UP PROCEDURES
The NexStar contains many user defined setup functions designed to give the user control over the
telescope’s many advanced features. All of the setup and utility features can be accessed by pressing
the
MENU key and scrolling through the options:
TRACKING MODE
Once the NexStar is aligned the tracking motors will automatically turn on and begin tracking the sky.
However, the tracking can be turned off for terrestrial use.
Alt-Az This is the default tracking rate and is used when the telescope
has been properly aligned.
EQ North Used
to track the sky when the telescope is polar aligned using
an equatorial wedge in the Northern Hemisphere.
EQ South Used to track the sky when the telescope is polar aligned using
an equatorial wedge in the Southern Hemisphere.
Off When using the telescope for terrestrial (land) observation the
tracking can be turned off so that the telescope never moves.
Note: The EQ North and EQ South tracking modes are only needed with telescopes that can
be polar aligned. The NexStar GT series are exclusively Alt-Az mounted telescopes and do
not require equatorial tracking.
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