Instruction Manual

ETX-90EC Astro Telescope ETX-105EC Astro Telescope ETX-125EC Astro Telescope
Meade Instruments Corporation

CONTENTS

WARNING!
Never use a Meade ETX Astro Telescope to look at the Sun! Looking at or near the Sun will cause instant and irreversible damage to your eye. Eye damage is often painless, so there is no warning to the observer that damage has occurred until it is too late. Do not point the telescope or its viewfinder at or near the Sun. Do not look through the telescope or its viewfinder as it is moving. Children should always have adult supervision while observing.
Quick-Start Guide.4 Telescope Electronic Controller Functions.5 ETX: Your Personal Window on the Universe.6 Telescope Controls.6 Electronic Controller Functions.8 Getting Started.9 Parts Listing.9 Assembly Instructions.9 Using the Viewfinder.10 Focusing the Viewfinder.10 Aligning the Viewfinder.10 Observation Techniques.11 Choosing an Eyepiece.11 Understanding Magnification.12 Terrestrial Observing.12 Astronomical Observing.13 Sidereal Rate.13 The Electronic Controller.13 Slew Speeds.13 Modes of Operation.14 Telescope Mountings.14 Alt/Az Mode.14 Polar Mode.15 Celestial Coordinates.16 Locating the Celestial Pole.16 Polar Alignment Procedure.16 Photography.18 A Few Tips on Photography.19 Optional Accessories.20 General Maintenance.22 Storage and Transport.22 Inspecting the Optics.23 Troubleshooting.23 Meade Customer Service.24 Telescope Specifications.25 Appendix A: Advanced Controller Functions.26 Tracking Motor Speed.26 Changing Modes.26 Appendix B: Helpful Charts.27 Latitude Chart for Major Cities of the World.27 Star Locator.27 Appendix C: Polar Alignment; Setting Circles.28 Precise Polar Alignment.28 Setting Circles.28 Appendix D: You and the Universe.29 Objects in Space.29 The Moon.29 Planets.29 Deep-Sky Objects.30
CAUTION! Use care to install batteries as indicated by the battery compartment. Follow battery manufacturer's precautions. Do not install batteries backward or mix new and used batteries. Do not mix battery types. If these precautions are not followed, batteries may explode, catch fire, or leak. Improperly installed batteries void your Meade warranty.
If you are anxious to use your ETX Astro Telescope for the first time, before a thorough reading of this instruction manual, see the QUICK-START GUIDE on page 4.
The name Meade, the Meade logo, and ETX are trademarks registered with the U.S. Patent Office and in principal countries throughout the world. All rights reserved. 2001 Meade Instruments Corporation.

QUICK-START GUIDE 1 4

Remove the ETX from its packaging and place it on a sturdy surface. Place the eyepiece (A) and viewfinder (B) into their appropriate positions on the telescope and tighten their respective attachment screws to a firm feel only.
Slide the Power Switch (E) on the Computer Control panel to the ON position. The lights flicker on the Electronic Controller. Press any key and the motors briefly move the telescope. The Electronic Controller is now operational.
H Slew Speed: Fast Medium Moderate Slow I D
Securely place the ETX on its side and remove the battery compartment cover (C) from the underside of the drive base. Insert eight (user-supplied) AA-size batteries into the battery compartment (D) in the proper orientation. Replace the cover and return the telescope to an upright position.
Use the Electronic Controller Arrow keys (H) to move the telescope up, down, left, and/or right. To change the telescopes slew speed, press the SPEED key (I). The indicator lights signify the speed, with the upper light showing the highest speed. Each press slows the speed down one level, then cycles back to the highest speed. NOTE: Before observing, verify that the flip-mirror control (14, Fig. 1) is in the up position. See FLIPMIRROR CONTROL, page 7, for more information.
NOTE: The telescope has rotational hard stops in the horizontal and vertical axes to prevent damage to the telescope. See page 6, for more information.
Verify that the Computer Control panel power switch (E) is in the OFF position. Remove the Electronic Controller (F) from the packing materials and plug it into the HBX port (G). Tighten the vertical and horizontal locks (6 and 9, Fig. 1) and then remove the dust cover (19, Fig. 1) from the end of the telescope tube.

Fork Arms - Hold the optical tube in place. Note: The telescope base and fork mount are designed with internal rotational limit stops. The horizontal limit stop prevents the telescope from rotating more than 360 to avoid damage to the internal wiring. The vertical limit stop prevents the viewfinder from contacting the fork mount when the telescope is pointed upward just past 90 and prevents the optical tube from contacting the base if pointed downward more than 30. Do not force the telescope to move beyond these stops or damage to the telescope will result.
Focus Knob - Moves the telescopes optical tube (5, Fig. 1) in a finely-controlled motion to achieve precise image focus. The ETX telescopes can be focused on objects from a distance of about 11.5 ft (ETX-90EC) or 15 ft (ETX-105EC or ETX-125EC) to infinity. Rotate the focus knob clockwise to focus on distant objects, and counterclockwise to focus on nearby objects. Horizontal Lock - Controls the manual horizontal rotation of the telescope. Loosen the horizontal lock counterclockwise to unlock the telescope, enabling it to be freely rotated by hand about the horizontal axis. Tightening the horizontal lock clockwise prevents the telescope from being rotated manually, but engages the horizontal motor drive clutch for Electronic Controller operation. When polar aligned, the horizontal lock serves as the Right Ascension, or R.A. lock (see RIGHT ASCENSION, page 16).
Computer Control Panel A. ON/OFF Switch - Turns the Computer Control Panel and Electronic Controller ON or OFF. Note: Always remove the batteries if they are not to be used for a long period of time. B. Auxiliary (AUX) Ports (2) - Provide connection for current and future Meade accessories, such as the Meade AstroFinder Software with #505 Cable Connector Kit, which allows you to control your ETX from a PC. See OPTIONAL ACCESSORIES, page 20. C. Handbox (HBX) Port handbox into this port. Plug the Electronic Controller or the optional #497 Autostar
D. 12v: The 12v connector is designed to accept an external power supply such as the optional #541 AC Adapter or the #607 Power Cord (see OPTIONAL ACCESSORIES, page 20). When one of the external power supply options is used, the internal batteries are disconnected from the power circuit. E. LED - The red power indicator light illuminates when power is supplied to the connected handbox and to the telescopes motor drive.
Base Housing - Supports the telescope for placement on a flat, level surface, such as a tabletop or optional tripod. See OPTIONAL ACCESSORIES, page 20. Holes for Optional Tripod - See your tripods instruction sheet for mounting information. Right Ascension (R.A.) Setting Circle - See page 28 for detailed information. Flip-Mirror and Flip-Mirror Control Knobs - ETX telescopes include an internal mirror. With the flipmirror control in the up position, as shown in Fig. 2a, light is diverted to the eyepiece. With the flipmirror control in the down position, as shown in Fig. 2b, light proceeds straight out the photo port for photography. See PHOTOGRAPHY, page 18. Note: The flip-mirror control is in the up position when the control is vertical (perpendicular to the telescope tube). To place the flip-mirror in the down position, turn the control until it is horizontal.

Telescope Focal Length Power = ____________________ Eyepiece Focal Length Example: To obtain the power of an ETX-125EC (which has a 1900mm focal length) using a SP 26mm eyepiece: 1900mm Power = ________ = 73X 26mm Use this formula to calculate the magnification obtained with a given eyepiece: Most observers should have 3 or 4 eyepieces plus the #126 2X Barlow to achieve the full range of reasonable magnifications possible with ETX models.
Note: Throughout this manual, you will notice the term "Alt/Az." Alt/Az is frequently used to refer to altitude or vertical and azimuth or horizontal. Alt/Az is just one of many methods used by amateur astronomers to help locate stars in the night sky.

Terrestrial Observing

All three of the ETX models make excellent, high-resolution terrestrial (land) telescopes. When you set the telescope on its drive base, as shown below in Fig. 9, you may use it for an extremely wide range of observations. When you look through the eyepiece at a terrestrial object, you will notice that the image is right-side-up, but reversed left-for-right. Normally, such an image orientation is not bothersome, unless you are trying to read a distant sign, for example. If the telescope is to be used for extensive terrestrial observations, a fully correctly oriented image is provided with the #Erecting Prism (see OPTIONAL ACCESSORIES, page 20). Viewing terrestrial objects requires looking along the Earth's surface through heat waves. Heat waves often degrade image quality. Low-power eyepieces, like the SP 26mm eyepiece, magnify these heat waves less than higher-power eyepieces. Therefore, low-power eyepieces provide a steadier, higherquality image. If the image in an eyepiece is fuzzy or ill-defined, reduce to a lower power. Observing in the early

Azimuth

Altitude
Fig. 9: Alt/Az mounting moves the telescope in vertical and horizontal directions.

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morning hours, before the ground has built up internal heat, results in better viewing conditions than during the lateafternoon hours.
If you wish to observe a distant land object, such as a mountain top or a bird, you can observe by merely pointing the telescope and looking through the eyepiece. Set the telescope on a table top or tripod, loosen the horizontal and vertical locks (6 and 9, Fig. 1), and turn the telescope towards the object you Fig. 10: Equatorial mounting aligns the telescope with the wish to observe. Look into the viewfinder celestial sphere (table-top tripod legs optional). and move the tube until you find the object. If the viewfinder is correctly aligned, the object now appears in the eyepiece. Center the object and focus the image using the by turning the focus knob (8, Fig. 1). Rotate the knob clockwise to focus on distant objects and counterclockwise to focus on nearby objects.

ris la Po

De cli na tio n

Astronomical Observing

As an astronomical instrument, your ETX telescope has many optical and electromechanical capabilities. It is in astronomical applications where the high level of optical performance is readily visible. The range of observable astronomical objects is, with minor qualification, limited only by the observers motivation.

Sidereal Rate

As the Earth rotates beneath the night sky, the stars appear to move from East to West. The speed at which the stars move across the sky is called the sidereal rate. You can observe stars and objects in the night sky using the terrestrial viewing method, but note that objects begin to slowly drift across and out of the eyepiece field. This motion is caused by the rotation of the Earth. You can counteract the drift by mounting the telescope to one of the optional tripods in the polar mode (see POLAR ALIGNMENT PROCEDURE, page 16). In this mode, the motor drive in each ETX model is designed to rotate the telescope at the sidereal rate so that it automatically follows, that is, "tracks" the stars. Tracking makes it easier to locate objects and to keep them centered in the telescopes eyepiece. The Electronic Controller supplied with your telescope assists with the tracking function.
Try to pick an observing site away from street and house lights, and car headlights. While this is not always possible, the darker the site, the better. Give your eyes about ten minutes to adjust to the darkness before observing. Give your eyes a rest from observing every ten or fifteen minutes to relieve eyestrain. Try not to use a standard flashlight. Seasoned observers use red LED flashlights or tape red cellophane over their flashlights for setup and map reading so they dont have to continually readjust their eyes to the darkness. Be careful not to shine bright lights if there are other observers in the area. Never shine a flashlight into a telescope while someone is observing! Dress warmly. It gets chilly when youre sitting for prolonged periods, even on some summer nights. Practice setting up your equipment during the day or in a lighted area to become familiar with it before going to a dark site. Use your 26mm eyepiece to view terrestrial objects and wider areas of space, such as open star clusters. Use your higher power eyepieces when you wish to view something up close, such as craters on the Moon or the rings of Saturn. Know your observing site. If youre going to try out an unfamiliar site, check it out in the daylight for possible obstructions and pitfalls.
The Electronic Controller
Functions of the Electronic Controller include: Slewing (moving) the telescope's optical tube assembly to an object Turning on the telescope motor drive to automatically track celestial objects (when the telescope is polar aligned) Changing the hemisphere of operation, when required Changing tracking speed (see APPENDIX A, page 26)

Fig. 11: Electronic Controller.

Slew Speeds

The Electronic Controller has four slew speeds that are directly proportional to the sidereal rate. Press the Speed key to change the slew speed. Note each slew speed corresponds to one of the four LED's of the Electronic Controller.

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Light 1 (top LED): The fastest speed. Use to move the telescope quickly from one point in the sky to another. Light 2: Best for centering an object in the viewfinder. Light 3: Best for centering an object in the field of a low-to-moderate power eyepiece, such as the standard SP 26mm. Light 4: The slowest speed. Use to center an object in the field of view of high-power eyepieces, such as the optional 6.7mm or 12.4mm. The four available speeds are: Light 1 = 1200 x sidereal (300 arc-min/sec or 5/sec) Light 2 = Light 3 = Light 4 = 180 x sidereal (45 arc-min/sec or 0.75/sec) 32 x sidereal (8 arc-min/sec or 0.13/sec) 8 x sidereal (2 arc-min/sec or 0.034/sec)
The two slowest speeds (8x and 32x sidereal) can be used for pushbutton (manual) tracking of astronomical objects while observing through the eyepiece.

Modes of Operation

The Electronic Controller can be set to operate in either of two primary modes: the Alt/Az mode (used when the telescope is operated in the altazimuth configuration; see below) and the polar mode (used when the telescope is polar- (or equatorial) aligned; see page 16). Choose the Alt/Az (altitude-azimuth, or vertical-horizontal) mode for all terrestrial operations of the telescope. In the Alt/Az mode, use the Arrow keys to slew the telescope to terrestrial or astronomical objects and, once you locate them, follow these objects if they move. However, in this mode astronomical tracking is not automatic and requires continuous pushes of the Arrow keys. The Electronic Controller is factory pre-set to the Alt/Az mode. Choose the polar mode when the telescope is equipped with either the optional #880 (ETX90EC) or #881 (ETX-105EC or ETX-125EC) Table Tripod, or #883 Deluxe Field Tripod, for extensive astronomical observations. In this mode use the Arrow keys to slew the telescope to objects. In addition, the telescopes internal motor drive is turned on, enabling the telescope to automatically track celestial objects. You can configure the two screws on the bottom rear of the Electronic Controller handbox to change the default mode of the Electronic Controller to Alt/Az or polar. When in polar mode, you may also set the alignment to the hemisphere in which you are located (not necessary in the Alt-Az mode). Caution: Mode screws A and B are the outer screws in the recess directly under the letters A and B on the rear of the Electronic Controller. Do not remove either of the inner two screws in the recess. Remove mode screw A (1, Fig. 12) to make the Northern hemisphere polar mode the automatic default of the Electronic Controller when power is applied (i.e., the motor drive is activated for operation in the Earths Northern Hemisphere). Remove mode screw B (2, Fig. 12) to make the Southern Hemisphere polar mode the automatic default of the Electronic Controller when power is applied (i.e., the motor drive is activated for operation in the Earths Southern Hemisphere ). Leave both the A and B screws in place (or remove both screws) to keep the telescope in the original factory default Alt/Az mode. Note: Removing either A or B screw affects only the telescopes default mode; you may still make mode changes when desired using the MODE key (see, APPENDIX A, page 26).

Telescope Mountings

A mount allows a telescope to move on its axes. The two basic types of mounting are Altazimuth (Alt/Az) and Polar (Equatorial).
35-4702-00 CC Tested to comply with FCC Standards

Alt/Az Mode

Altazimuth (Alt/Az) mounting permits movement of the telescope tube in vertical (altitude) and horizontal (azimuth) directions. The ETX models incorporate an altazimuth mount (as shown in Fig. 9), ideal for terrestrial

FOR HOME OR OFFICE USE

Fig. 12: Mode screws on rear of Electronic Controller. (1) Mode screw A; (2) Mode screw B.

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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 ETX125EC 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. 2. 3. 4. 5. 6. 7. 8. 9. Set the telescope on a level and stable surface, or mount to the Meade #883 Deluxe Field Tripod (see
OPTIONAL ACCESSORIES, page 20).
Insert a low-power eyepiece (e.g., SP 26mm) into the eyepiece holder (4, Fig. 1) and tighten the eyepiece thumbscrew (3, Fig. 1). Tighten the vertical and horizontal locks (6 and 9, Fig. 1), if necessary. Verify that the power switch (10A, Fig. 1) on the telescopes Computer Control panel is OFF. Plug in the Electronic Controller coil cord (4, Fig. 3) to the HBX port (10C, Fig. 1) on the Computer Control panel. 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. Press any key on the Electronic Controller and the telescope slews momentarily in the vertical and horizontal directions to test the motors. When the test is complete, light 1 remains on; lights 2, 3, and 4 turn off. 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.

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 Meades 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. Youll 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

Locating the Celestial Pole
To get basic bearings at an observing location, take note of where the sun rises (East) and sets (West) each day. After the site is dark, face North by pointing your left shoulder toward the direction where the sun set. To point at the pole, find Polaris by using the Big Dipper as a guide (Fig. 14).
Polar Alignment Procedure
As the Earth rotates once on its axis every 24 hours, astronomical objects appear to move across the sky in an arc. This apparent motion (see SIDEREAL RATE, page 13) is not obvious to the unaided eye, but viewed through a telescope such as the ETX-90EC, ETX-105EC, or ETX-125EC, this motion is rapid indeed. If the motor drive has not been engaged, objects centered in the telescopes eyepiece move entirely out of the field of view in 30 to 160 seconds, depending on the magnification employed. For easy tracking of astronomical objects your ETX telescope should be polar aligned.
North Celestial Pole (Vicinity of Polaris) +90 Dec. Star

ation clin De

Earths Rotation

Right Ascension

Celestial Equator 0 Dec.

South Celestial Pole

-90 Dec.
Fig. 13: The Celestial Sphere.

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There are two mounting methods available to polar align the telescope depending on whether you use the optional #883 Deluxe Field Tripod or a table tripod (specific to your model of ETX telescope). To polar align using the #883 Deluxe Field Tripod (Fig. 17), follow the instructions provided with the tripod. To polar align using the #880 (ETX-90EC) or #881 Table Tripod (ETX-105EC or ETX125EC, Fig. 16), use the following procedure. 1. Make sure the viewfinder is aligned with your ETX telescope (see ALIGNING THE VIEWFINDER, page 10).

Little Dipper

Polaris

Big Dipper

Fig. 14: Locating Polaris.

Cassiopeia

2. Remove the two hole covers (12, Fig. 1) from the side of the drive base and thread the two identical fixed legs (4, Fig. 16) into these holes to a firm feel only. 3. Determine the latitude of the observing location from a road map, atlas, or the Latitude Chart for Major Cities of the World, page 27; determining the latitude within about one degree is sufficient. 4. Each table tripod is equipped with two adjustable tripod legs, only one of which will be used: The standard tripod leg is used at observing latitudes as shown in step 5 and has a dual latitude label attached (Fig. 15). The high-latitude tripod leg is shorter and is used at higher observing latitudes. 5. Locate the two mounting holes on the bottom of the telescope drive base. Mount the appropriate adjustable tripod leg to the drive base using the following latitudes: Standard Tripod Leg (ETX-90EC) 32.5 to 48.5 uses high-latitude hole (2, Fig. 16). 22 to 35.5 uses alternate hole (3, Fig. 16). High-Latitude Tripod Leg (ETX-90EC) 56 to 66 uses high-latitude hole. 44 to 55 uses alternate hole. Standard Tripod Leg (ETX-105EC, ETX-125EC) 33.5 to 49.5 uses high-latitude hole. 23.25 to 36.5 uses alternate hole. High-Latitude Tripod Leg (ETX-105EC, ETX-125EC) 56.6 to 67 uses high-latitude hole. 44.5 to 56.5 uses alternate hole. Thread the appropriate leg into the required hole to a firm feel only. Set aside the tripod leg that is not to be used. 6. A small thumbscrew (6, Fig. 16) is attached to both the standard and high-latitude tripod legs. Loosening the thumbscrew allows the outer section of the leg to slide over the inner section, so that the leg can be extended. If using the standard tripod leg, extend the leg so that the center of the thumbscrew head aligns with the latitude of the observing location on the scale. Retighten the thumbscrew to a firm feel. (If using the high-latitude tripod leg, complete the adjustment of the leg extension in step 9.) Example: The latitude of New York City is 41. The tripod leg should be extended so that the center of the thumbscrew is set next to the 41 reading on the scale. Note: With the standard tripod leg threaded into the appropriate hole in the drive base, the latitude scale may be at an inconvenient position for reading (e.g., the scale faces the drive base). This situation can be remedied by unthreading the leg, removing the thumbscrew, rotating the inner leg 180, then reinserting the thumbscrew. The scale will now be readable when threaded back into the telescope base. 7. Loosen the vertical and horizontal locks (6 and 9, Fig. 1) and rotate the telescope so that it is oriented as shown in Fig. 16. Tighten the vertical

PHOTOGRAPHY

Photography through your ETX model requires the addition of the optional #64 T-Adapter (see OPTIONAL ACCESSORIES, page 20). With the #64 T-Adapter attached to the telescope (Fig. 18), through-the-telescope photography is possible with any 35mm camera body with a removable lens. In this way the telescope effectively becomes the lens of the camera. For through-the-telescope photography, turn the flip-mirror control (5, Fig. 18) to the down position, allowing light to pass straight through the telescope and out the photo port (15, Fig. 1). With the flip-mirror control in the down position and the photo ports dust cover removed, you can see the front lens of the telescope when you look through the photo port. The #64 T-Adapter threads onto the photo port, followed by a T-mount for the particular brand of 35mm camera being used, followed by the camera body (with the camera lens removed). The #64 T-Adapter consists of two sections (1 and 2, Fig. 18), which are threaded together in shipment. You may use either of the following photographic mounting formats to couple the camera body to the telescopes photo port thread. Format 1: Camera Body + T-Mount + Section (1) of the #64 T-Adapter (7, Fig. 18). ETX-90EC ETX-105EC ETX-125EC 1250mm at f/13.8 1640mm at f/15.6 1900mm at f/15
Format 1 utilizes only the short section of the #64 T-Adapter to permit close-coupling of a camera body to the telescope. In this format vignetting will occur: the photographic image will appear on film with a slight darkening at the corners of the 35mm frame (see Fig. 19). Format 2: Camera Body + T-Mount + Sections (1) and (2) of the #64 T-Adapter (see Fig. 18). ETX-90EC ETX-105EC ETX-125EC 1450mm at f/16 1830mm at f/17.4 2310mm at f/18

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Format 2 utilizes both sections of the #64 T-Adapter threaded together to form a rigid unit. In this configuration there is no field vignetting: images are illuminated to the edges of a standard 35mm frame (see Fig. 20). To frame an object in the viewfinder of the 35mm camera body, slightly loosen the knurled attachment ring (3, Fig. 18), which threads the #64 TAdapter to the telescopes photo port; rotate the camera body to achieve proper framing of the object; then retighten the knurled ring.
Fig. 18: Example of photography through the ETX using the Photography through a long lens, such #64 T-Adapter: (1) Short section of #64 T-Adapter; as the ETX, requires special technique (2) Extension section of #64 T-Adapter; (3) Knurled attachment for good results. The photographer ring; (4) T-mount; (5) Flip-mirror control in down position; (6) should expect to use a roll or two of 35mm camera body; (7) Format 1. film in acquiring this technique. Longlens photography has its own rewards, however, which short-focus lenses cannot duplicate. A Few Tips on Photography 1. Use the optional table tripod specific to your model of ETX, or the #883 Deluxe Field Tripod as a platform for the telescope. At effective focal lengths of 1250mm to 1450mm (ETX-90EC), 1640mm to 1830mm (ETX-105EC), or 1900mm to 2310mm (ETX125EC), even small external vibrations can easily ruin an otherwise good photo. CAUTION: With the #64 T-Adapter and a camera body mounted to the ETX photo port, the telescope can be rotated vertically only 45. Moving past this point may damage the telescope and camera. 2. Use a cable-operated shutter release. Touching the camera body to operate the shutter will almost certainly introduce undesirable vibrations. Fig. 19: Example of a format 1 photo. 3. Focus the image with extreme care. While observing the subject through the cameras reflex viewfinder, turn the ETX's focus knob (8, Fig. 1) to achieve the sharpest possible focus. Note that some 35mm cameras may have an optional focusing screen (available from the manufacturer) for use with a long telephoto lens. This screen provides a brighter and clearer image to focus and is highly recommended. 4. Correct shutter speeds vary widely, depending on lighting conditions and film used. Trial-and-error is the best way to determine proper shutter speed in any given application. Note: The camera used with an ETX model may have an exposure meter that is still active when the standard lens is removed and the body is connected to the telescope with the T-mount. If used for terrestrial photography, the camera meter should be acceptable. If used for astrophotography, the meter probably will not provide good results since camera meters are not made to compensate for a dark sky. 5. Terrestrial photography through an ETX model is sensitive to heat waves rising from the Earths surface. Long distance photography is best accomplished in the early morning hours before the earth has had time to build up heat. 6. Photography of the Moon and planets through an ETX model can be especially gratifying, but points 1 through 4 should be particularly noted in this case. Lunar or planetary photography requires that the telescope be polar aligned (see POLAR ALIGNMENT PROCEDURE, page 16), and that the telescopes motor drive be in operation (see APPENDIX A, page 26). Note: Long-exposure photography of deep-sky objects is not practical with an ETX model, since this type of photography requires special electronic and optical guiding devices not available for this telescope.

Slow-Motion Controls. electric, 4 speed, both axes Optional Autostar Capability. yes Hemispheres of operation. North and South, switchable Bearings: Altitude. ball bearings Azimuth. PTFE thrust bearing and radial ball bearing Materials: Tube body. aluminum Mounting. ABS, with internal aluminum structure Primary mirror. Pyrex glass Correcting lens. BK7 optical glass, Grade-A
Telescope dimensions:. 43cm x 25cm x 20cm (17 x 10 x 8)
Telescope net weight: (incl. Electronic Controller & batteries). 6.1kg (13.5 lbs) Telescope shipping weight. 8.3kg (18.4 lbs) Battery Life (approx.): with Electronic Controller. 45 hrs with Autostar. 20 hrs
Specifications: ETX-125EC Astro Telescope
Optical design. Maksutov-Cassegrain Primary mirror diameter. 138mm (5.43) Clear aperture. 127mm (5.0) Focal length. 1900mm (74.8) Focal ratio (photographic speed). f/15 Near focus (approx). 5.5m (18 ft) Resolving power. 0.9 arc secs Super multi-coatings (EMC). standard Limiting visual stellar magnitude (approx.). 12.5 Image scale. 0.76/inch Maximum practical visual power. 500X Optical tube dimensions (dia. x length). 14.6cm x 36cm (5.75 x 14.2) Eyepiece. Super Plssl 26mm Viewfinder. 8 x 25mm right-angle Secondary mirror obstruction (dia.; %). 39.4mm (1.6); 9.6% Telescope mounting. fork type; double tine Setting circle diameters. Dec.: 4.3; RA: 9 Input voltage. 12 volts DC Motor Drive System. DC servo motors with encoders, both axes Slow-Motion Controls. electric, 4 speed, both axes Optional Autostar Capability. yes Hemispheres of operation. North and South, switchable Bearings: Altitude. ball bearings Azimuth. ball bearings Materials: Tube body. aluminum Mounting. ABS, with internal aluminum structure Primary mirror. Pyrex glass Correcting lens. BK7 optical glass, Grade-A
Specifications: ETX-105EC Astro Telescope
Optical design. Maksutov-Cassegrain Primary mirror diameter. 116mm (4.56) Clear aperture. 105mm (4.13) Focal length. 1470mm (57.8) Focal ratio (photographic speed). f/14 Near focus (approx). 4.6m (15 ft) Resolving power. 1.1 arc secs Super multi-coatings (EMC). standard Limiting visual stellar magnitude (approx.). 12.1 Image scale. 0.99/inch Maximum practical visual power. 420x Optical tube dimensions (dia. x length). 12.4cm x 32.8cm (4.88 x 12.9) Eyepiece. Super Plssl 26mm Viewfinder. 8 x 25mm right-angle Secondary mirror obstruction (dia.; %). 3.3cm (1.32); 9.4% Telescope mounting. fork type; double tine Setting circle diameters. Dec.: 3.81; RA: 7.8 Input voltage. 12 volts DC Motor Drive System. DC servo motors with encoders, both axes - 25 -
Telescope dimensions:. 48cm x 23cm x 27cm (19 x 8.9 x 10.8)
Telescope net weight: (incl. Electronic Controller & batteries). 6.9kg (15.2 lbs) Telescope shipping weight. 11.4kg (25.2 lbs) Battery Life (approx.): with Electronic Controller. 45 hrs with Autostar. 20 hrs

Appendix A: ADVANCED ELECTRONIC CONTROLLER FUNCTIONS

Tracking Motor Speeds

In the polar mode the Electronic Controller normally tracks objects at the sidereal rate (see SIDEREAL RATE, page 13). For most observing sessions (once the telescope has been polar aligned and the tracking motor activated), there is little need to change this speed. For objects, like the Moon or a comet, that move at slightly different rates, the Electronic Controller Arrow keys (1, Fig. 3) are sufficient to move the telescope slightly as the object very slowly moves off-center through the eyepiece field. To change the tracking rate, for extended observations of an object not moving at the sidereal rate, follow the procedure for the appropriate hemisphere:
Northern Hemisphere Polar:
1. 2. 3. Press and hold the MODE key (5, Fig. 3) until the Mode function is active (i.e., lights 1 and 2 are on steady; lights 3 and 4 signify whatever tracking mode was last chosen). Press the SPEED key (3, Fig. 3) until lights 1, 2, and 3 are on steady with light 4 blinking. The telescope is now in the Northern Hemisphere polar mode. Press the IN key (7, Fig. 3) and light 4 comes on steady. The tracking rate is now 0.5% faster than sidereal. If the object you're tracking is moving faster than the sidereal rate, look through the eyepiece and continue to press the IN key until the object remains centered with little or no drifting in the eyepiece. Note: The tracking rate can be increased by up to 65% (127 presses of the IN key). 4. To use a rate slower than sidereal, press the OUT (6, Fig. 3) key until light 4 blinks again (sidereal rate). Press the OUT key again and light 4 goes out, signifying a tracking rate 0.5% slower than sidereal. If the object you're tracking is moving slower than the sidereal rate, look through the eyepiece and continue to press the OUT key until the object remains centered with little or no drifting in the eyepiece. Note: The tracking rate can be decreased by up to 65% (127 presses of the OUT key). 5. Press and hold the MODE key until only a single light is on. This exits the Mode function. If Northern or Southern Hemisphere polar mode was chosen, the motor drive starts operating at the sidereal rate. 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.

Pegasus 23h05m 15 12" Piscis Austrinus 22h58m -29 38" Cetus 02h19m -02 58" Orion Orion Canis Major Taurus 05h15m 05h55m 06h45m 04h35m -08 12" 07 25" -16 43" 16 31"

SOUTH AMERICA

Bogot So Paulo Buenos Aires Montevideo Santiago Caracas ASIA

Country

Colombia Brazil Argentina Uruguay Chile Venezuela

Latitude

4 N 23 S 35 S 35 S 34 S 10 N
Beijing Hong Kong Seoul Taipei Tokyo Sapporo Bombay Calcutta Hanoi Jedda AFRICA
China China South Korea Taiwan Japan Japan India India Vietnam Saudi Arabia

N N N N N N N N N N

Amsterdam Athens Bern Copenhagen Dublin Frankfurt Glasgow Helsinki Lisbon London Madrid Oslo Paris Rome Stockholm Vienna Warsaw
Netherlands Greece Switzerland Denmark Ireland Germany Scotland Finland Portugal England Spain Norway France Italy Sweden Austria Poland
52 N N N N N N N N N N N N N N N N N

23 N S N N S

Cairo Egypt Cape Town South Africa Rabat Morocco Tunis Tunisia Windhoek Namibia AUSTRALIA AND OCEANIA
Adelaide Brisbane Canberra Alice Springs Hobart Perth Sydney Melbourne Auckland

State/Country

South Australia Queensland New South Wales Northern Territory Tasmania Western Australia New South Wales Victoria New Zealand

37 S S S S S S S S S

Appendix C: PRECISE POLAR ALIGNMENT; SETTING CIRCLES
If desired, you may obtain more precise polar alignment by first accomplishing basic polar alignment as detailed in POLAR ALIGNMENT PROCEDURE, page 16, then returning to this procedure: Important Note: For almost all astronomical observing requirements, approximate settings of the telescopes latitude and polar axis are acceptable. Do not allow undue attention to precise polar alignment of the telescope to interfere with your enjoyment of the instrument. Note: This procedure moves the telescope physically to line up precisely with the celestial pole. Do not use the Electronic Controller Arrow keys to move the telescope electronically or polar alignment will be lost. 1. Orient the entire telescope, including tripod or tripod legs, so that the polar axis is pointing toward Polaris (Fig. 14). 2. While observing through the SP 26mm eyepiece of the telescope, adjust the length of the adjustable tripod leg until Polaris is visible in the eyepiece. Use a combination of (a) lifting and turning the entire telescope (or nudging the position of one of the fixed tripod legs) and (b) adjusting the length of the adjustable tripod leg to place Polaris in the center of the telescope's field. 3. Repeat step 2 of this procedure in about 15 minutes to see how much drift has taken place and to make the alignment more precise. Although the above procedure is somewhat tedious (since the field of view of the telescope with the SP 26mm eyepiece is only about 1), it is a worthwhile effort if precise polar alignment is desired (e.g., if photography of the Moon or a planet is to be performed). With Polaris placed in the center of the telescopes eyepiece, the telescope is now polar aligned within about one or two degrees, a level of alignment precision more than sufficient for almost any observing application. To provide the most stable platform from which to polar align the ETX models, it is recommended to purchase the #883 Deluxe Field Tripod. The tripod head tilts easily to the local latitude angle for quick polar alignment, and it locks in a 90 position to facilitate Alt/Az viewing (see OPTIONAL ACCESSORIES, page 20).

To use the setting circles to find astronomical objects, the ETX must first be polar aligned. It is advisable that the motor drive be turned on (see APPENDIX A, page 26) and that a low-power eyepiece (e.g., the SP 26mm eyepiece) be employed. Then use the following procedure: 1. Identify the celestial coordinates (R.A. and Dec.) of a bright, easy-to-find object, such as a bright star. (Avoid using Polaris or any object near Polaris.) Coordinates of bright stars are listed in the STAR LOCATOR, page 27, astronomy magazines, text books, or star charts. Center this object in the telescopes field of view. 2. Manually turn the R.A. circle (13, Fig. 1) to read the R.A. of the object at the R.A. pointer (7, Fig. 16). 3. The R.A. circle is now calibrated to read the correct R.A. of any object at which the telescope is pointed. The Dec. circle is already calibrated through polar alignment. 4. To find another object, again identify the R.A. and Dec. coordinates. Then, without touching the setting circles, move the telescope (manually, by unlocking the vertical and horizontal locks, or by slewing the telescope using the Electronic Controller Arrow keys) so that the R.A. and Dec. pointers read the coordinates of the second object. 5. If the above procedure has been followed carefully, the second object will now be in the telescopes field of view. Note: Since the second object (i.e., the object to be located) is in constant motion, once the R.A. circle is calibrated (step 2, above) the telescope should be moved rapidly to read the coordinates of the second object. Otherwise the second object will no longer be in the position indicated by the R.A. circle. Using setting circles requires a developed technique. When using the circles for the first time, try hopping from one bright star (the calibration star) to another bright star of known coordinates. Practice moving the telescope from one easy-to-find object to another. In this way the precision required for accurate object location becomes familiar.

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Appendix D: YOU AND THE UNIVERSE

OBJECTS IN SPACE

In the early 17th century, Italian Scientist Galileo, using a crude telescope considerably smaller than the ETX-90EC, turned it to look towards the sky instead of distant trees and mountains. What he saw, and what he realized about what he saw, forever changed the way mankind thinks of the universe. Imagine what it must have been like being the first human to see moons revolve around the planet Jupiter or to see the changing phases of Venus! Because of his observations, Galileo correctly realized Earth's movement and position around the Sun, and in doing so, gave birth to modern astronomy. Yet Galileo's telescope was so crude, he could not clearly make out the rings of Saturn. Galileo's discoveries laid the foundation for understanding the motion and nature of the planets, stars, and galaxies. Building on his foundation, Henrietta Leavitt determined how to measure the distance to stars; Edwin Hubble proposed a glimpse into the origin of the universe; Albert Einstein unraveled the relationship of time and light; and 21st-century astronomers are currently discovering planets around stars outside our solar system. Almost daily, using sophisticated successors to Galileo's crude telescope, such as the Hubble Space Telescope and the Chandra X-ray telescope, more and more mysteries of the universe are being solved and understood. We are living in the golden age of astronomy. Unlike other sciences, astronomy welcomes contributions from amateurs. Much of the knowledge we have on subjects such as comets, meteor showers, variable stars, the Moon, and our solar system comes from observations made by amateur astronomers. So as you look through your Meade ETX telescope, keep in mind Galileo. To him, a telescope was not merely a machine made of glass and metal, but something far morea window through which the beating heart of the universe might be observed.

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Fig. 34: Jupiter and its four largest moons. The moons can be observed in a different position every night.
Jupiter (Fig. 34) is the largest planet in our solar system, with a diameter 11 times that of Earth. Jupiter appears as a disk with dark lines stretching across the surface. These lines are cloud bands in the atmosphere. Four of Jupiters 29 (and still counting!) moons (Io, Europa, Ganymede, and Callisto) can be seen as star-like points of light when you use even the lowest magnification. The number of moons visible on any given night changes as they circle around the giant planet. Saturn (Fig. 35) is nine times the diameter of Earth and appears as a small, round disk with rings extending out from either side. In 1610, Galileo, the first person to observe Saturn through a telescope, did not understand that what he was seeing were rings. Instead, he believed that Saturn had ears. Saturns rings are composed of billions of ice particles. The major division in Saturn's rings, called the Cassini Division, is generally visible through all three ETX models. Titan, the largest of Saturns moons, can also be seen as a bright, star-like object near the planet.

Further Study.

This manual gives only the briefest introduction to astronomy. If you are interested in pursuing further studies in astronomy, a few topics are suggested below that are worth reading up on. Try looking up some of these in the optional Autostar glossary. Also included below is a small sampling of books, magazines, and organizations that you might find helpful. Topics 1. How is a star born? How does a solar system form? 2. How is the distance to a star measured? What is a light year? What is red shift and blue shift? 3. How are the craters on our Moon formed? How old is the Moon and Earth? How old is the Sun? 4. What is a black hole? A neutron star? 5. What are stars made of? Why are stars different colors? What is a white dwarf? A red giant? Have we ever seen the surface of a star besides our own sun? 6. What is a nova? A supernova? 7. What are comets? Minor planets? Meteors? Meteor showers? Where do they come from? 8. What is a planetary nebula? A globular cluster? 9. What is the Big Bang? Is the universe expanding or contracting, or does it always remain the same? What is dark matter? 10. What is an extrasolar planet? What is an accretion (or protoplanetary) disk? 11. What is the difference between an elliptical, a spiral, and an irregular galaxy? Books 1. 2. 3. 4. The Guide to Amateur Astronomy by Jack Newton and Philip Teece The Sky: A Users Guide by David Levy Turn Left at Orion by Guy Consolmagno & Dan Davis Astrophotography for the Amateur by Michael Covington Sky & Telescope Box 9111, Belmont, MA 02178 Astronomy Box 1612, Waukesha, WI 53187 Astronomical League Executive Secretary 5675 Real del Norte, Las Cruces, NM 88012 The Astronomical Society of the Pacific 390 Ashton Ave, San Francisco, CA 94112 The Planetary Society 65 North Catalina Ave, Pasadena, CA 91106

Operating Instructions

Meade #884 Deluxe Field Tripod
For use with all ETX telescopes

Introduction

The Meade #884 Tripod allows an ETX telescope to be mounted in either the altazimuth or the equatorial mode. The assembly includes a latitude adjustment control and a tilt-plate incorporated into the design. Parts List Tripod (1) with attached tilt-plate (2) and latitude adjustment control (3) with latch (4). Two attachment knobs (5) for attaching an ETX telescope to the tilt-plate. Spreader tray (6). Separate spring, two washers, and tension knob (7) to attach tray to tripod. Three leg extension lock knobs (8). How to assemble the tripod
Step 1: Spread the tripod (1) legs apart to a fully open position.
Step 2: Slide the spreader tray (6) onto the central threaded rod.
Step 3: Slide a washer, followed by the spring, another washer, and the tension knob (7) onto the threaded rod. Tighten the tension knob to a firm feel.
Step 4: Adjust the height of the tripod by loosening the leg lock knobs (8) and adjusting the height of the inner leg exten-sions. Then retighten the lock knobs.
Note: It is not necessary to tighten the spring (Step 3) to a fully compressed position. Tighten until the spreader tray holds the legs tightly without slipping.

Mounting your Telescope

As the Earth rotates on its axis, astronomical objects appear to move across the sky in an arc. This apparent motion is not obvious to the unaided eye, but when viewed through a telescope such as an ETX, this motion is rapid indeed. If the motor drive has not been engaged, celestial objects viewed in the telescope eyepiece drift entirely out of the field of view in 15 to 60 seconds, depending on the magnification employed. However, by mounting your telescope and turning on the motor drive, you can counteract the drift of objects in the eyepiece. The two basic types of mounting are: altazimuth (alt/az) and equatorial. It is unnecessary for ETX owners who use an Autostar Controller to equatorially mount the telescope. The Autostar Controller allows the telescope to be mounted in the altazimuth (alt/az) mode for all observing purposes. If you are using the ETX-70AT: Skip the "Equatorial Mount" section, below, and follow the procedure described in the section entitled "Altazimuth (Alt/Az) Mount." If you are using the ETX-90/105/125 equipped with the optional Autostar hand controller: Skip the "Equatorial Mount" section, below, and follow the procedure described in the "Altazimuth Alt/Az Mount" section. If you are using the ETX-90/105/125EC with Electronic Controller (EC): Follow the procedures in the "Equatorial Mount" section and skip the section entitled "Altazimuth (Alt/Az) Mount." If you are using the ETX-90RA: Follow the procedures in the "Equatorial Mount" section and skip the section entitled "Altazimuth (Alt/Az) Mount." Equatorial Mount If you are using the Electronic Controller, use equatorial mounting. Mounting the telescope in this configuration lines up the telescope's polar axis with the North Celestial Pole (or the South Celestial Pole if observing in the southern hemisphere). When using an equatorially mounted telescope, tracking (following) celestial objects is possible by turning on your ETX telescope's motor drive. The motor counteracts the Earth's rotation and keeps objects in the field of view of the eyepiece for hands-off tracking.
Equatorial Mounting Procedure 1. Loosen the latitude control latch (4, Fig. 1) and lift up the tilt-plate (2, Fig. 1) so that you can easily access the underside of the plate. Relock the latitude control latch, so the assembly doesn't slip while you are attaching the telescope. (See Fig. 1.) 2. Turn the tripod, so that the face of the tilt-plate points North (Figs. 7 and 8). If you attach the telescope to the tripod indoors, be sure to orient the face of the tilt-plate to point North after moving the telescope outdoors. Equivalently, point the tripod leg (9, Fig. 7) North. This is the leg opposite from the latitude control bar (3, Fig. 7). ETX-90RA model: Line up the two mounting holes of your telescope over the attachment knobs (5, Fig. 3). Thread the attachment knobs into the base of the telescope. Tighten to a firm-feel only. Important Note about the ETX-90RA model: The On/Off switch is located on the base of the drive base. This switch must be turned on before the telescope is mounted to the tilt-plate. ETX-90EC, ETX-105EC, and ETX-125EC models with Electronic Controller (EC): Line up the mounting hole on the base of the telescope labeled "High Latitude Leg" with the attachment knob that is closest to the latitude control bar (see Fig. 2). Line up the other mounting hole with the remaining attachment knob. Thread both attachment knobs into the base of the telescope. Tighten to a firm-feel only. (See Fig. 3.) 4. Determine the latitude of your observing location from a road map, atlas, or the LATITUDE CHART FOR MAJOR CITIES OF THE WORLD, provided in your ETX manual. Loosen the latitude control latch (4, Fig. 4) and adjust the latitude control bar (3, Fig. 4) so that your observing site's latitude is just visible above the flat surface of the tripod head. Retighten the latch. (See Fig. 4.) If you have not already done so, orient the tripod leg (9, Fig. 7) so that it is pointing due North (if the location of Polaris, the North Star, is known, point the telescope directly at Polaris. Observers located in the Earths Southern Hemisphere must point the telescope due South). (See Figs. 7 and 8.) The telescope is now equatorially mounted; the tripod must not be moved, or else the alignment will be lost. Instead, use one of the following methods to move the telescope's optical tube to a desired celestial object. (a) Loosen the Horizontal (R.A.) and/or Vertical (Dec.) locks (see your telescope Operating Instructions) to permit the optical tube to be freely moved manually. Tighten the locks once you center on the object. (b) With the Horizontal and Vertical locks in their locked positions, use the manual slow-motion controls (ETX-90RA models) or the Arrow keys of the Electronic Controller (ETX-90EC, ETX-105EC, and ETX-125EC models) to move the optical tube. Note: For most astronomical observing requirements, approximate settings of the telescope's latitude and North-pointing tripod leg (steps 4 and 5, above) are acceptable. Do not allow undue attention to precise equatorial mounting of the telescope to interfere with your enjoyment of the instrument. Using an Equatorially Mounted Telescope Once your telescope is equatorially mounted, the telescope motor drive will keep a celestial object in the telescope eyepiece's field of view. To activate the tracking feature: 1. 2. Center a celestial object in the eyepiece. See the appropriate section in your telescope's operating instructions for more information about locating celestial objects. Activate your telescope's motor drive. The telescope now tracks the centered object. ETX-90RA models: The On/Off switch is located on the base of the drive base. This switch must be turned on before the telescope is mounted to the tilt-plate. The telescope will automatically track astronomical objects: see the telescope's operating instructions for details in this regard. Use the telescope's manual slow motion controls to make minor adjustments to keep an object centered. ETX-90EC, ETX-105EC, and ETX-125EC models with Electronic Controllers: The On/Off switch is located on the telescope's Computer Control panel. The telescope will automatically track astronomical objects; see the telescope's operating instructions for details in this regard. Use the Electronic Controller's Arrow keys to make minor adjustments to keep the object centered.

Fig. 1: Loosen control latch (4).
High latitude leg mounting hole. Attachment knob.

Latitude control bar.

Fig. 2: High latitude leg mounting hole and corresponding attachment knob.
Fig. 3: Attach telescope to tripod.

Fig. 4: Set latitude.

Note: If your telescope does not begin tracking when you activate the motor drive (you should hearing a "whirring" sound), check the configuration of the "mode screws" on the back of the Electronic Controller. See "Modes of Operation" in your telescope's operating instructions for more information. Caution: Do not move the tripod or adjust the latitude setting while observing, or the mounting alignment will be lost. Note: The telescope's motor drive disengages when the Horizontal and the Vertical lock levers are unlocked and re-engages when the levers are relocked. 3. At the end of an observing session, remember to turn off the motor drive.
Altazimuth (Alt/Az) Mount Ideal for both terrestrial applications and also for astronomical observation with Autostar. Altazimuth (alt/az) mounting (from "altitude" meaning vertical and "azimuth" meaning horizontal) permits movement of the telescope tube in both the vertical (altitude) and the horizontal (azimuth) directions. To mount your telescope in the alt/az mode: 1. Loosen the latitude control latch (4, Fig. 1) and lift up the tilt-plate (2, Fig. 1) so that you can easily access the underside of the plate. Relock the latitude control latch, so the assembly doesn't slip while you are attaching the telescope. (See Fig. 1.) 2. ETX-70AT model: Line up the two mounting holes of your telescope over the attachment knobs (5, Fig. 3). Thread the attachment knobs into the base of the telescope. Tighten to a firm feel only. ETX-90EC, ETX-105EC, and ETX-125 models with Autostar: Line up the mounting hole on the base of the telescope marked "High Latitude Leg" with the attachment knob that is closest to the latitude control bar (see Fig. 2). Line up the other mounting hole with the attachment knob at the bottom of the tilt-plate. Thread both attachment knobs into the base of the telescope. Tighten to a firm feel only. (See Fig. 3.) Unlock the latitude control latch (4, Fig. 4) and lower the tilt-plate until it is level (push the tilt-plate down until it stops; this is the level position). Lock the latitude control latch. (See Fig. 6.)
Using an Alt/Az Mounted telescope The telescope is now altazimuth mounted on the #884 Tripod. Motions of the telescope may be effected in either horizontal or vertical directions. ETX telescopes equipped with an Autostar hand controller (standard equipment with the ETX-70AT: optionally available for the ETX-90EC, ETX-105EC, and ETX-125EC) may be used in the altazimuth mode, and the Autostar hand controller directs the telescope to track astronomical objects in both vertical and horizontal directions, simultaneously. Note that in the case of altazimuth mounting, the orientation of the tripod is irrelevant: the tripod may be placed on the ground with tripod legs pointing in arbitrary directions. For information on the use of your ETX telescope equipped with an Autostar hand controller, consult your telescope's operating instructions.

North Celestial Pole

Fig. 6: Altazimuth Alignment. Note that the tilt-plate is level.
Fig. 7: Example of Polar Alignment. Note that the face of the tilt-plate points North.
Fig. 8: Example of Polar Alignment. Note that the face of the tilt-plate points North.
Locating the Celestial Pole
Using the North Star (Polaris) to find North is useful in equatorial mounting. Polaris is the tail star of the Little Dipper; however, the Little Dipper is made up of dim stars and is not always easily located. A simple way of locating Polaris is to draw an imaginary line from the so-called "pointer" stars of the Big Dipper to Polaris (see diagram below). In the Southern hemisphere, locate South by using the faint star Sigma Octantis (the South Star).

Little Dipper

Polaris

Big Dipper

Fig. 9: Locating Polaris.

Cassiopeia

If you have a question concerning use of the Meade #884 Deluxe Field Tripod, call the Meade Instruments Customer Service Department at (949) 451-1450, or fax to (949) 451-1460. Customer Service hours are 8:30 AM to 4:30 PM, Pacific Time, Monday through Friday.

ADVANCED

PRODUCTS

DIVISION

Meade Instruments Corporation
Worlds Leading Manufacturer of Astronomical Telescopes for the Serious Amateur
6001 Oak Canyon, Irvine, California 92618 I (949) 451-1450 FAX: (949) 451-1460 I www.meade.com

Part no. 14-0269-00

Ver. 6-02