Meade 114 EQ-DS instruction manual Balancing the Telescope, Alignment of the Viewfinder

Models: 114 EQ-DS

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Remove the viewfinder bracket mounting nuts from the viewfinder bracket mounting bolts (16) that protrude from the optical tube (12), near the focuser (17). Place the viewfinder bracket’s mounting holes (located at the base of the bracket) over the mounting bolts, so that the bracket is oriented as shown in Fig. 1. Replace the viewfinder bracket mounting nuts, and tighten to a firm feel. Then center the viewfinder in both bracket rings by backing off the three thumbscrews (26) on each bracket ring. Orient the viewfinder so its front objective lens is pointing in the same direction as the open end (front) of the optical tube (25).

Position the cradle ring attachment (37) onto the optical tube saddle plate (13), with the mid-point lying roughly in the center of the saddle plate. Tighten the cradle ring lock knob (36) to a firm feel when the cradle ring attachment is positioned in the telescope’s saddle (13).

If the cradle ring assmbly did not come already attached to the optical tube assembly (12), loosen the lock knobs (15) of the cradle rings (14) and open the cradle rings. Place the optical tube assembly roughly in the center of the cradle rings and close the rings over the tube. Then tighten the cradle ring lock knobs (15) to a firm feel; do not overtighten these knobs. Please note that you may want to change the rotational position of the optical tube to gain a more comfortable observing position of the focuser (17). This adjustment may be performed several times in one observing session, as desired.

Insert the H 25mm eyepiece (19) into the focuser, and tighten the focuser thumbscrew (18) to secure the eyepiece.

The telescope is now fully assembled. Before it can be properly used, however, the telescope must be balanced and the viewfinder aligned.

Balancing the Telescope

In order for the telescope to move smoothly on its mechanical axes, it must first be balanced about the 2 telescope axes: the polar axis (10, Fig. 1c) and the Declination axis (21, Fig. 1c). All motions of the polar aligned telescope (more on this later) take place by moving about these two axes, separately or simultaneously. To obtain a fine balance of the telescope, follow the method below:

Loosen the R.A. lock (22, Fig. 1c) and rotate the telescope so that the counterweight shaft (6, Fig. 1c) is parallel to the ground (horizontal).

Slide the counterweight along the counterweight shaft until the telescope remains in one position without tending to drift down in either direction. Then tighten the counterweight lock knob (7, Fig. 1c), locking the counterweight in position.

Lock the R.A. lock (22, Fig. 1c), and unlock the Declination lock (23, Fig. 1c). The telescope will now turn freely about the Declination axis. Loosen the cradle ring lock knobs (15, Fig. 1e) so that the main tube in the cradle rings slides easily up-or-down in the cradle rings. Move the main tube in the cradle rings until it is balanced rotationally about the Declination axis. Re-lock the knobs (15, Fig. 1e).

The telescope is now properly balanced on both axes.

Alignment of the Viewfinder

The wide field of view provided by the 5 x 24mm viewfinder permits easy object sighting prior to observation in the higher-power main telescope. The 5 x 24 Viewfinder (24, Fig. 1a) and viewfinder bracket (20, Fig. 1a) attaches to the telescope tube assembly as described above (see Fig. 1a). In order for the viewfinder to be functional, however, it must be aligned to the main telescope, so that both the viewfinder and main telescope point at the same position in the sky. With this simple alignment performed, finding objects is greatly facilitated, since you will first locate an object in the wide-field viewfinder, then you will look in the eyepiece of the main telescope for a detailed view. To align the viewfinder follow these steps:

Remove the telescope front dust cover (25, Fig. 1e), and the dust covers of the viewfinder.

Place the low- power (H 25mm) eyepiece into the focuser of the main telescope.

Unlock the R.A. lock (22, Fig. 1c) and the Dec. lock (23, Fig. 1c) so that the telescope turns freely on both axes. Then point the main telescope at some well-defined land object (e.g. the top of a telephone pole) at least 200 yards distant, and re-lock the R.A and Dec. axes. Turn the flexible cable controls, (3, Fig. 1e) and (4, Fig. 1e), to center the object in the telescopic field.

With the front of the viewfinder already centered in the front bracket ring, look through the viewfinder and loosen or tighten, as appropriate, one or more of the rear viewfinder bracket ring thumbscrews (26, Fig. 1a) until the viewfinder’s crosshairs are likewise centered on the object previously centered in the main telescope.

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Meade 114 EQ-DS instruction manual Balancing the Telescope, Alignment of the Viewfinder