Polar Mode

applications and for casual astronomical observation. The telescope may be placed on a rigid tabletop or on the optional Meade #883 Deluxe Field Tripod (see OPTIONAL ACCESSORIES, page 20) to provide a

secure, variable-height, altazimuth observing platform. To manually track objects with the telescope in the altazimuth configuration, press the Arrow keys of the Electronic Controller as necessary to keep an object centered.

Note: Automatic tracking of objects is not possible with the ETX-90 EC, ETX-105EC and the ETX- 125EC in the Alt/Az mounting.

With the Electronic Controller in the factory pre-set “Alt/Az” (vertical-horizontal) mode, the Electronic Controller Arrow keys permit pushbutton movements (slewing) of the telescope.

To move the telescope using the Electronic Controller:

1.Set the telescope on a level and stable surface, or mount to the Meade #883 Deluxe Field Tripod (see

OPTIONAL ACCESSORIES, page 20).

2.Insert a low-power eyepiece (e.g., SP 26mm) into the eyepiece holder (4, Fig. 1) and tighten the eyepiece thumbscrew (3, Fig. 1).

3.Tighten the vertical and horizontal locks (6 and 9, Fig. 1), if necessary.

4.Verify that the power switch (10A, Fig. 1) on the telescope’s Computer Control panel is OFF.

5.Plug in the Electronic Controller coil cord (4, Fig. 3) to the HBX port (10C, Fig. 1) on the Computer Control panel.

6.Flip the power switch to ON. The power indicator (10E, Fig. 1) on the Computer Control panel lights and all four speed indicators (2, Fig. 3) blink rapidly.

7.Press any key on the Electronic Controller and the telescope slews momentarily in the vertical and

horizontal directions to test the motors.

8.When the test is complete, light 1 remains on; lights 2, 3, and 4 turn off.

9. Use the four Arrow keys (1, Fig. 3) to slew the telescope to the desired object. To change the slew speed, press the SPEED key.

10.Fine-adjust the position of the object with the Electronic Controller Arrow keys so that it is centered in the viewfinder. The object is now ready to be viewed through the telescope’s eyepiece.

If you are to use your ETX-90EC, ETX-105EC, or ETX-125EC telescope for extensive astronomical applications, it is recommended

you use Polar or Equatorial mounting. By

tilting one of the telescope’s mechanical axes (see Fig. 10) to point at the celestial pole (i.e., by pointing one axis of the telescope to the North Star, Polaris), you may follow (track) astronomical objects through the sky.

The telescope's optical tube turns on only one axis of the telescope instead of simultaneously turning on two axes, as required of the

Altazimuth mount. An Equatorial mount which has one of its axes (the polar axis) pointing to the celestial pole is said to be polar aligned. The ETX

models can be polar aligned either by using the optional #883 Deluxe Field Tripod or the table tripod specific to your model of ETX telescope

(see OPTIONAL ACCESSORIES, page 20).

With the ETX polar aligned, the telescope’s internal motor drive may be activated (see APPENDIX A, page 26) to enable fully automatic hands-off tracking of celestial objects. In this

TIPS FOR BEGINNERS

Surf the Web

One of the most exciting resources for astronomy is the Internet. The Internet is full of websites with new images, discoveries, and the latest astronomical information. For example, when comet Hale-Bopp made its approach to our Sun in 1998, astronomers around the world posted new photos daily.

You can find websites for virtually any topic relating to astronomy on the internet. Try the following key word searches: NASA, Hubble, HST, astronomy, Messier, satellite, nebula, black hole, variable stars, extrasolar, Chandra, gamma burster, etc.

Check out Meade’s website for the latest product and technical information. You can download the latest software revisions, links to other astronomical sites, coordinates of celestial objects and the latest satellite tracking information for the optional #497 Autostar handset. See page 20 for more information. You’ll find our website at:

http://www.meade.com/

Here are some other sites you might find useful:

•Sky & Telescope: http://www.skypub.com/

•Astronomy: http://www.astronomy.com/astro/

•The Starfield: http://users.nac.net/gburke/

•Astronomy Picture of the Day: http://antwrp.gsfc.nasa.goc/apod/

•Heavens Above (satellite observing information): http://www.heavens-above.com/

•Photographic Atlas of the Moon: http://www.lpi.ursa.edu/research/lunar_orbiter

•Hubble Space Telescope Public Pictures

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