selected telescope.
• Az Ratio and Alt Ratio: The Az (Azimuth)
ratio and Alt (Altitude) ratio refers to the
gears of the telescope’s motors. Do not alter
these numbers.
• Az Percent: The Az (Azimuth) Percent allows
you to change the azimuth backlash, i.e., the
way the arrow keys move the telescope along
the azimuth (horizontal) axis. If you enter a
value near 100, the telescope tube responds
more quickly (it responds immediately at 100%)
as you hold down an arrow key and also slews
(moves) the tube more quickly. If you enter
a value near 0, it takes longer for the tube to
respond as you hold down an arrow key and
also slews the tube more slowly. Experiment
with this option. Try changing the percent value
until you get a “feel” for the arrow keys that is
comfortable for you.
• Alt Percent: The Alt (Altitude) Percent operates
identical to the Az Percent option (see above),
but allows you to change the altitude backlash,
i.e., the way the arrow keys move the telescope
when moving along the altitude (vertical) axis.
• Train Drive: Trains the Altitude and Azimuth
motors to locate objects with more precision.
If you are experiencing any problems with
pointing accuracy, follow the procedure
described in APPENDIX A: TRAINING THE
DRIVE, Page 57, to insure accurate pointing
and tracking.
• Tracking Rate: Changes the speed at which
the telescope tracks targets in the sky.
a. Sidereal: The default setting for AudioStar;
sidereal rate is the standard rate at which
stars move from East to West across the
sky due to the rotation of the Earth.
b. Lunar: Choose this option to properly track
the Moon over long observing sessions.
c. Custom: Allows entry of user-defi ned
tracking rates.
• Reverse L/R reverses the functions of the Left
and Right Arrow keys (i.e., the Right key moves
the telescope to the left).
• Reverse UP/DOWN reverses the functions of
the Up and Down Arrow keys (i.e., the Up key
moves the telescope down).
• Quiet Slew sets the maximum slew rate to 1.5°
for quieter operation.
• Max Elevation allows you to enter a value in
degrees that sets a limit as to how far the optical
tube can swing upward during a programmed
slew. (Note that it does not prevent you from
performing a manual slew past this limit.) This
is useful when you have a camera or other
peripheral attached to the telescope—you can
prevent it from striking the telescope base.
• Min AOS (Acquisition of Signal) allows you
enter a value in degrees. This value represents
the altitude at which your telescope begins
to slew when acquiring a satellite track. This
is useful when you are observing satellites,
but a tall tree or building is obstructing the
telescope. For example, you might begin to
track the satellite at 15° altitude, instead of 5°.
See Observing Satellites, Page 45, for more
information about satellites.
• Calibrate Motor if the telescope motors appear
to have a problem, use this option to retest the
motors before performing a Reset. This option
is also used if an AudioStar unit is moved
between telescopes, to match AudioStar to the
new telescope. To calibrate the motors, select
this option and press ENTER.
• High Precision if turned on, when looking for
a faint celestial object (i.e., a nebula or galaxy),
AudioStar fi rst slews to a nearby bright star and
displays “ENTER to Sync”. Center the star in
the eyepiece, then press ENTER. At that point
the telescope has a high precision alignment
to that part of the sky and it then slews to the
object that was originally requested.
Targets switches between Astronomical targets and
Terrestrial targets. If “Astronomical” is selected, the
telescope tracking motor is activated and any object
you observe will remain centered in the eyepiece.
If “Terrestrial” is selected, the tracking motor is
turned off.
Site provides access to several options including:
AudioStar #497 HANDBOX
AudioStar Operation
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