Meade Instruments Corporation
Telescopes · Binoculars · Microscopes

Meade Apochromatic Refrators Instruction Manuals
Models 102ED, 127ED, 152ED, and 178ED
IMPORTANT NOTICE! Never use a telescope or spotting scope to look at the Sun! Observing the Sun, even for the shortest fraction of a second, will cause irreversible damage to your eye as well as physical damage to the telescope or spotting scope itself.
Use the following steps to assemble your telescope.

[ toc ] 1. Unpacking

Meade APO refracting telescopes are packed in five cartons as follows:

Carton #1:

  • The complete optical tube assembly (OTA) with cradle rings and dew shield. (Note: The 7" APO only has the dew shield packed separately in Carton #3.)
Carton #2:
  • The complete equatorial head with field tripod adapter.
Carton #3: (Accessories)
  • 8 x 50mm straight-through viewfinder with quick-release bracket.
  • #930 2"/1.25" Diagonal Mirror.
  • Series 4000 SP26mm eyepiece.
Carton #4:
  • Counterweight(s)
Carton #5:
  • Field Tripod (4" and 5") or Giant Field Tripod (6" and 7").
Carefully unpack and remove all the telescope parts from their packing material. Compare the parts to the "Packing Program" (packed with the telescope) to identify each part (refer to Fig. 4).

NOTE: We strongly recommend that you keep all packing materials. If it is ever necessary for you to return your telescope to the Meade factory for servicing, these materials will help ensure that no shipping damage will occur.

Figure 1: Field Tripod

[ toc ] 2. The Field Tripod

The Field Tripods for the Meade APO refracting telescopes are supplied as completely assembled units, except for the spreader bar (4, Fig. 1) and the 6 lock knobs (5, Fig. 1) (2 knobs for each of the 3 tripod legs) used to adjust the height of the tripod. These knobs are packed separately for safety in shipment.

After removing the field tripod from its shipping carton, stand the tripod vertically, with the tripod feet down and with the tripod still fully collapsed (see Fig. 2). Grasp two of the tripod legs and, with the full weight of the tripod on the third leg, gently pull the legs apart to a fully open position.

Thread in the 6 lock-knobs (2 on each tripod leg) near the foot of each tripod leg. Refer to Fig. 1. These lock-knobs are used to fix the height of the inner, extendible tripod leg section. Note: "Firm feel" tightening is sufficient; over-tightening may result in stripping of the knob threads or damage to the tripod legs and results in no additional strength.

The spreader bar (4, Fig. 1) has been removed for shipment. To install, first remove the hex nut from the top of the threaded rod (2, Fig.1) and remove the threaded rod from the tripod head (1, Fig. 1). [Note: the threaded rod has a knob (3, Fig. 1) permanently attached.] Remove the second hex nut from the threaded rod. These two hex nuts will not be used.

Slide the spreader bar onto the threaded rod (note the correct orientation as shown in Fig. 2) and position the threaded rod back through the tripod head. Place the clip retainer (a "C" clip) into the slot in the threaded rod. This clip holds the threaded rod in place. See Fig. 2.

Position the spreader bar so that the 3 arms of the spreader bar are lined up with the 3 tripod legs.

Attach the equatorial head as described below.

To vary the tripod height, loosen the 6 lock-knobs and slide the 3 inner tripod leg sections out to the desired height. A bubble level is included on both the LXD 650 and LXD 750 mounts to aid in leveling the field tripod.

To collapse the tripod (after removing the telescope and equatorial mount) for storage, follow these steps:

    1. Lower the tripod legs to the lowest position.

    2. Rotate the spreader bar (4, Fig. 1) 60° from its assembled position, so that one spreader bar arm is located between each adjacent pair of tripod legs.

    Figure 2: Field Tripod (Collapsed)

    3. At the base of the tripod is a 3-vane extension strut system, with a circular hub at its center (7, Fig. 1). To collapse the tripod, grasp the tripod head (1, Fig 1) with one hand and, with the other hand, pull directly "up" on the central hub of the extension strut system. This operation will cause the tripod legs to move inward to a collapsed position.


1. If the tripod does not seem to extend or collapse easily, do not force the tripod legs in or out. By following the instructions above, the tripod will function properly, but if you are unclear on the proper procedure, forcing the tripod into an incorrect position may damage the extension strut system.

2. Do not overtighten the 6 lock-knobs used to fix the inner tripod leg sections at various heights. "Firm feel" tightening is sufficient.

[ toc ] 3. Mounting the Equatorial Head to the Field Tripod

Figure 3: Attaching the Field Tripod Adapter

To attach the equatorial head to the field tripod, follow these steps:

    1. Remove the field tripod adapter (13, Fig. 4; also 3, Fig. 3) from the bottom of the equatorial head. This has been shipped attached to the equatorial head to prevent damage to the azimuth stud (1, Fig. 3). Loosen the azimuth knobs (12, Fig. 4) slightly to release the field tripod adapter.

    2. Attach the field tripod adapter to the field tripod using the three 1/2"-20 screws supplied. (These three screws are shipped with the field tripod adapter.) Align the azimuth stud with one of the tripod legs as shown in Fig. 3, and thread the three screws up through the bottom of the tripod head and into the bottom of the field tripod adapter. Firmly tighten the three screws, so that the tripod head and the field tripod adapter are rigidly connected. The field tripod adapter may be left permanently attached to the field tripod.

    3. Place the equatorial head onto the top of the field tripod adapter. Be sure the two azimuth knobs are unthreaded far enough to allow the equatorial head to slide past the azimuth stud.

    4. Thread the threaded rod (2, Fig. 1) up into the equatorial head using the tension knob (3, Fig. 1). Be sure to keep the spreader bar aligned with the tripod legs as the field tripod and equatorial head combination tightens up. Tighten the tension knob to a "firm feel," over-tightening may deform the tripod legs and does not result in a more rigid system.

[ toc ] 4. Attaching the Counterweight(s)

Figure 4: Apochromatic Refractor Head
Figure 5: Apochromatic Refractor

1. The equatorial head has been shipped with the latitude angle roughly set to 0°. In this "shipping" position, the counterweight will not clear the tripod leg, therefore, the latitude angle should be set before the counterweight can be attached. Loosen the latitude lock lever (11, Fig. 4) and turn the latitude adjustment knob (5, Fig. 5) until the latitude scale indicates the correct latitude of your viewing location. (Determine the latitude of your viewing location by checking a road map or atlas.) Retighten the latitude locking lever.

2. Loosen the counterweight shaft locking lever (12, Fig. 5) and lower the counterweight shaft (9, Fig. 5). Lock into place by retightening the counterweight shaft locking lever.

3. Remove the counterweight safety stop (8, Fig. 5) from the end of the counterweight shaft.

4. Slide the one (or two) counterweights (10, Fig. 5) onto the counterweight shaft and lock into place by tightening the counterweight lock lever (7, Fig. 5).

5. Replace the counterweight safety stop onto the end of the counterweight shaft.

CAUTION: Never operate the telescope without the counterweight safety stop in place.

[ toc ] 5. The Dew Shield

The 4", 5", and 6" APO telescopes have been shipped with the dew shields (1, Fig. 4) already installed onto the optical tube assembly and held in place with a safety screw (20, Fig. 4). The dew shield for the 7" APO telescope is shipped separately in carton #3. Use the following steps to attach the 7" dew shield:

    1. Remove the dew shield safety screw from the bottom of the lens cell (2, Fig. 4).

    2. Position the dew shield onto the end of the optical tube assembly, taking care to align the safety screw hole with the bottom of the lens cell.

    3. Replace the dew shield safety screw.

Be sure that the dew shield safety screw is always in place whenever using any Meade apochromatic telescope.

[ toc ] 6. Mounting the Cradle Ring Assembly and OTA to the Equatorial Mount

The cradle ring assembly (4, Fig. 4) has been shipped on the optical tube assembly (OTA) (3, Fig. 4). Use the following procedure to attach the cradle rings to the equatorial head.

    1. Loosen the two cradle ring knobs (16, Fig. 5) and remove the cradle ring assembly from the OTA.

    2. Remove the two 3/8"-16 bolts from the top of the Declination cover casting (15, Fig. 5) and attach the cradle ring assembly using these two bolts. Firmly tighten these two bolts.

    Once attached, the cradle ring assembly may be left permanently attached to the equatorial head.

    3. Before placing the optical tube assembly into the cradle ring assembly (step 4, below), be certain that the R.A. lock lever (8, Fig. 4) and Dec. lock lever (5, Fig. 4) are firmly locked.

    4. Place the optical tube assembly (3, Fig. 4) into the cradle ring assembly (16, Fig. 4) and secure by closing the cradle ring. Tighten the two cradle ring knobs.

    5. Immediately perform the balancing procedure ("Balancing the Telescope") described below.

[ toc ] 7. Mounting the Viewfinder

Each Meade APO telescope is supplied as standard equipment with an 8x50mm straight-through viewfinder. The bracket for this viewfinder is packed separately from the finder itself, and the 6 nylon thumbscrews for collimation should be threaded into the viewfinder bracket, securing the viewfinder in the bracket. The viewfinder bracket base has been factory-mounted to the main telescope's rear cell, and will accept the viewfinder and bracket directly, allowing quick removal for storage.

[ toc ] a. Attaching the Viewfinder

To attach the viewfinder, slide the viewfinder and bracket into the base and tighten the two thumbscrews (located on the viewfinder bracket base) to a "firm feel."

WARNING: Never use set screws on any part of the optical tube assembly, except those factory supplied set screws included with the basic telescope or with optional accessories. Longer, non-standard set screws may protrude too far into the optical tube and cause serious damage to the telescope.

Figure 6: 8x50mm Viewfinder

[ toc ] b. Focusing the Viewfinder

The 8x50mm viewfinder has been factory pre-focused to infinity. Should this focusing need adjustment for your eyes, loosen the knurled collar at the objective lens-end of the viewfinder (3, Fig. 6), enabling rotation of the objective lens cell (2, Fig. 6) forward or backward for precise focusing. Then tighten down the knurled collar against the objective lens cell to lock the focus in place. Note that no focusing is possible or necessary at the eyepiece end of the viewfinder.

[ toc ] c. Collimating the Viewfinder

The viewfinder will require alignment, or collimation, with the main telescope. Using the 26mm eyepiece, point the main telescope at some easy to find land object (e.g., the top of a telephone pole or corner of a building) at least 200 yards distant. Center a well-defined object in the main telescope. Then, turn the 6 nylon collimation thumbscrews (4, Fig. 6) until the crosshairs of the viewfinder are precisely centered on the object already centered in the main telescope. With this collimation accomplished, objects located first in the wide-field viewfinder will then be centered in the main telescope's field of view.

[ toc ] 8. Attaching Diagonal and Eyepiece

The #930 Diagonal Mirror (17, Fig. 4) slides into the focuser drawtube (15, Fig. 4) and, in turn, accepts the supplied 1-1/4" O.D. eyepiece. For astronomical observations, the diagonal mirror generally provides a more comfortable right-angle viewing position. Alternately, an eyepiece may be inserted directly into the focuser drawtube (using the diagonal mirror's 1-1/4" adapter) for straight-through observations*. Note in this case, however, that the image will appear inverted and reversed left-for-right. With the diagonal mirror, telescopic images appear correctly oriented up-and-down, but still reversed left-for-right. For terrestrial applications, where a fully corrected image orientation is desired, both up-and-down and left-for-right, the optional #924 or #928** Erecting Prism (1-1/4" O.D.) should be ordered separately. Eyepieces and the diagonal mirror are held in their respective places on the telescope by a moderate tightening of the thumbscrews on the diagonal mirror.

[ toc ] 9. Balancing the Telescope

In order for the telescope to move smoothly on its mechanical axes, it must first be balanced, as follows:

    1. Loosen the Right-Ascension (R.A.) lock (8, Fig. 4) and rotate the telescope so that the counterweight shaft (9, Fig. 5) is parallel to the ground (horizontal).

    2. Loosen the counterweight lock lever(s) (7, Fig. 5) and slide the counterweight(s) along the shaft until the telescope remains in one position without tending to drift in either direction. Retighten the counterweight lock lever(s).

    3. Loosen the Declination lock lever (5, Fig. 4) and rotate the optical tube assembly (OTA) so that the OTA is parallel with the ground (horizontal).

    4. Loosen the two cradle ring lock knobs (16, Fig. 5) slightly and slide the OTA inside the cradle ring until the optical tube remains in one position without tending to fall in either direction. Retighten the cradle ring lock knobs, locking the OTA at this position.

    5. The telescope is now properly balanced.

* Note, however, that straight-through observing through a Meade ED apochromatic refractor may require an optionally-available extension tube, in order to reach correct focus.

** See the latest Meade General Catalog.

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