Meade LX90GPS instruction manual JThe telescopes limiting positions

Models: LX90GPS

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JThe telescope's limiting positions

Important Tip:

It is recommended that you train your telescope’s drive the first time you align your telescope. Training the drive improves your telescope’s pointing precision.

For more information about pointing your telescope, see page 56 for more information.

IMPORTANT NOTE: While performing the automatic tracking, only use the Arrow keys to move the tele- scope. Once the tele- scope has been set in the Alt/Az home posi- tion, do not loosen the telescope locks (6 and 9, Fig. 1), or move the base manually, or alignment will be lost.

IMPORTANT NOTE:

The "Telescope: Mount" option of the Setup menu is set to "Alt/Az" as the default alignment by the factory.The example presented in this section assumes that you are performing an alignment procedure for the first time with your telescope and therefore, the "Telescope: Mount" option does not need to be selected. For information on equatorial (Polar) alignment, see APPENDIX A,” page 50.

AutoStar also determines the positioning (i.e., tilt and tip) of the optical tube.

b.Finds North. Locates magnetic North, then calculates true North. See FINDING TRUE NORTH, page 21.

c.Attempts a "GPS Fix." The GPS receiver attempts to acquire and sync up with signals from GPS satellite system. "Getting GPS Fix" displays. See THE GLOBAL POSITIONING SYSTEM on page 21.

After performing these operations, AutoStar now knows:

JThe telescope's limiting positions

JWhere level is for the telescope

JThe location of true North

JThe observing site's location

JThe date and time

Note: Press any key to abort the GPS fix. You will then be prompted to enter the time, date and location.

d.Once the level, tilt and North are detected, the telescope will “Go To” 2 alignment stars. The telescope will go to these stars in order to orient itself to the sky. Once it has done this, it will be able to point to any of the more than 30,000 stars in its database.

“Automatic Alignment: Selecting Star” and “Slewing” display. Finally, when it is close to the

alignment star “Center Brightest Star: Press ENTER” displays. Use the Arrow keys to center the alignment star in the eyepiece. The alignment star will be the brightest star in that area of the sky (and hence, “brightest star”). When the alignment star is entered, press ENTER.

Note: If you press the “?” key while “Ctr Brightest Star” displays, the alignment star that

AutoStar has chosen will display. For example, “Arcturus: Press ENTER” may display.

Note: If you have an obstruction, such as a tree or a building blocking your view of the align- ment star, or if you have any doubts at all about the star that has been chosen, no problem. Just press the Scroll Down key and AutoStar will find another star to align upon.

However, when the telescope slews to the first star, it may not appear in the field of view in the eyepiece. Use the SmartFinder (17, Fig. 1) and /or the viewfinder (1, Fig. 20) to locate the star. The alignment star will be easy to recognize—it will be the brightest star in the area of the sky where the telescope is pointing. Look through the SmartFinder or the viewfinder and use the Arrow keys to move the telescope until the star is visible. Then look through the eyepiece and center the star using the Arrow keys. Press ENTER. Repeat the procedure for the second alignment star.

When the procedure is performed correctly, "Alignment Successful" displays. If AutoStar does not display this message, perform this procedure again.

NOTE: The alignment stars may change from night to night. All that is required is for the observer to center the selected stars in the eyepiece when prompted.

6.The telescope now slews to the second alignment star. AutoStar displays “Center Brightest Star: Press ENTER” displays. Use the Arrow keys to center the alignment star in the eyepiece. When the second alignment star is centered, press ENTER.“

7.“Alignment successful” displays. If “Alignment Unsuccessful” displays, perform the procedure over again.

Observe a Star using the Automatic Tracking Feature

Now that your telescope has been aligned, you are able to track celestial objects. In this exam- ple, the AutoStar Arrow keys are used to find a star, and then AutoStar's tracking capability automatically keeps the star centered in your telescope's eyepiece.

1.When Automatic Alignment is completed (as described in the previous section), "Select: Object" displays on AutoStar II.

2.Select a bright star from one of the Object menus. You may choose any unobstructed, bright star for the purposes of this example. Use the viewfinder (22, Fig. 1) to help line up on the star. Use AutoStar's Arrow keys to center the star in the eyepiece. The tracking motors will then keep the star you have chosen in the center of the eyepiece.

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Meade LX90GPS instruction manual JThe telescopes limiting positions