Orion 9738 instruction manual Knobs, Installing the Finder Scope

of the central support shaft until the three tray arms are touching the legs of the tripod. The flat side of the acces- sory tray should be facing up. Make sure the “V” of each tray arm is against a tripod leg. Place the washer back on the center support shaft against the tray, and thread the securing knob all the way up the center support shaft until it is tight against the tray. The tripod support tray provides additional stability for the tripod, and holds five 1.25" eye- pieces and two 2" eyepieces.

Azimuth	Post
adjustment
knobs

Figure 2. Orient the equatorial mount so that the post on the tripod head lines up with the azimuth adjustment knobs on the equatorial mount.

5.Thread the Latitude adjustment L-bolt into the rear of the of the equatorial mount casing as shown in place in Figure 1.

6.Thread the counterweight shaft into the equatorial mount at the base of the declination axis until tight. Make sure the casting at the top is threaded clockwise as far as it will go before attaching the shaft. Once the shaft is installed, turn the casting counter-clockwise until the top of the casting is flush with the mount.

7.Remove the knurled “toe saver” retaining screw on the bottom of the counterweight shaft and slide both counter- weights onto the shaft. Make sure the counterweight lock knobs are adequately loosened to allow the counterweight shaft to pass through the hole. Position the counterweights about halfway up the shaft and tighten the lock knobs. Replace the toe saver at the end of the bar. The toe saver prevents the counterweights from falling on your foot if the lock knobs happen to come loose.

8.Attach the slow-motion control knobs to the right ascen- sion and declination gear shafts of the equatorial mount by sliding them onto the shaft. Line up the flat on the end of the gear shaft with thecorresponding feature in the inte- rior of the knob to attach them properly. The knobs can be attached to either end of the shafts; use whichever end is most convenient.

9.Attach the tube mounting rings to the tube mounting plate using the attachment screws that are on the tube rings. The screws should go through the holes on the outer ends

of the mounting plate and rethread into the tube rings. Note that the side of the mounting plate with the central “groove” will be facing up. Use the small wrench to secure the tube rings to the mounting plate.

10.Loosen the black mounting plate securing knob as well as the metal safety thumbscrew. Place the mounting plate in the dovetail slot on top of the equatorial mount. Position the mounting plate so that it is centered on the dovetail slot. Re-tighten the mounting plate securing knob until the mounting plate is secure. Then, tighten the safety thumbscrew. The safety thumbscrew will ensure that the mounting plate (and telescope tube) will not fall off the EQ mount if the mounting plate securing knob should come loose.

11.Open the tube rings and lay the telescope optical tube in the rings at about the midpoint of the tube’s length. Rotate the tube so that the focuser is at a convenient height for viewing. Close the tube rings and tighten them.

Installing the Finder Scope

To place the finder scope (Figure 3a) in the finder scope brack- et, unthread the two black nylon thumbscrews until the screw ends are flush with the inside diameter of the bracket. Place the O-ring that comes on the base of the bracket over the body of the finder scope until it seats into the slot on the middle of the finder scope. Slide the eyepiece end (narrow end) of the finder scope into the end of the bracket’s cylinder opposite the alignment thumbscrews while pulling the chrome, spring-load- ed tensioner on the bracket with your fingers (Figure 3b). Push the finder scope through the bracket until the O-ring seats just inside the front opening of the bracket cylinder. Release the ten- sioner and tighten the two alignment thumbscrews a couple of turns each to secure the finder scope in place. Insert the base of the finder scope bracket into the dovetail holder on the top of the focuser. Lock the bracket into position by tightening the knurled thumbscrew on the dovetail holder.

Finder scope bracket	Nylon
	alignment
	thumbscrews
Finder scope

Tensioner

Focus lock ring

Figure 3a. The 8x40 finder scope.

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