Meade 114 EQ-ASB instruction manual Maintenance

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MAINTENANCE

Cleaning

As with any quality instrument, lens or mirror surfaces should be cleaned as infrequently as possible. Front surface aluminized mirrors, in particular, should be cleaned only when absolutely necessary. In all cases avoid touching any mirror surface. A little dust on the surface of a mirror or lens causes negligible loss of performance and should not be considered reason to clean the surface. When lens or mirror cleaning does become necessary, use a camel’s hair brush or compressed air gently to remove dust. If the telescope’s dust cover is replaced after each observing session, cleaning of the optics will rarely be required.

Mount and Tripod Adjustments

Every Meade 114 EQ-ASB equatorial mount and tripod is factory inspected for proper fit and function prior to shipment.

The tripod legs have wingnuts (39, Fig. 1c), and Phillips-head screws (38, Fig. 1c) that may have backed off. They may be tightened to a firm feel for a more sturdy performance of the telescope.

Collimation (Alignment) of the Optics

All Meade 114 EQ-ASB telescopes are optically aligned at the factory prior to shipment. It is unlikely that you will need to align, or collimate, the optics after receipt of the instrument. However, if the telescope received unusually rough handling in shipment, it is possible that the optics must be re aligned for best optical performance. In any case this alignment procedure is simple, and requires only a few minutes the very first time the telescope is used. Take the time to familiarize yourself with the following collimation procedure, so that you will recognize a properly collimated instrument and can adjust the collimation yourself, if necessary.

a. Correct collimation

The properly collimated (aligned) mirror system in the Meade 114 EQ-ASB assures the sharpest images possible. This occurs when the primary mirror and diagonal mirror are tilted so that the focused image (see Fig. 4) falls directly through the center of the focuser drawtube (17, Fig. 1b). These mirror tilt adjustments are made with the diagonal assembly (Fig. 5) and the primary mirror cell (Fig. 6), and will be discussed later.

To inspect the view of the mirror collimation, look down the focuser drawtube with the eyepiece removed. The edge of the focuser drawtube (1, Fig. 7), will frame the reflections of the primary mirror with the 3 mirror clips (2, Fig. 7), the diagonal mirror (3, Fig. 7) , the spider vanes (4, Fig. 7), and your eye (5, Fig. 7). Properly aligned, all of these reflections will appear concentric (i.e., centered) as illustrated in Fig. 7.

Any deviation from the concentric reflections will require adjustments to the diagonal assembly (Fig. 5), and/or the primary mirror cell (Fig. 6).

b. Diagonal holder adjustments

If the diagonal mirror (1, Fig. 8) is centered in the drawtube (2, Fig. 8), but the primary mirror is only partially visible in the reflection (3, Fig. 8), the 3 Phillips-head diagonal tilt screws (1, Fig. 5). Note: To adjust these screws you must first remove an adhesive backing) must be unthreaded slightly to the point of where you can tilt the diagonal holder (3, Fig. 5) from side-to-side by grasping the diagonal holder with your hand and tilt until you see the primary mirror become as centered in the reflection of the diagonal mirror as possible. Once you are at the best position, thread in the 3 Phillips-head diagonal tilt screws to lock the rotational

DiagonalMonture	MDiagonalroir DiagonalMirror	Primary Mirror
AssemblyDiagonale		Miroir Primaire
		PromaryVis D'inclinaisonMirror-Tilt
	ImageFocusedFocaliséeImage	du MiroirScrewsPrimaire

Fig. 4: The Newtonian Reflecting Telescope.