Meade TRUSS DOBONIAN 10, LIGHT BRIDGE 8, TRUSS DOBONIAN 12, TRUSS DOBONIAN 8, LIGHT BRIDGE10 Instruction Manual

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Instruction Manual

8”, 10", 12" LightBridge™ Truss Tube Dobsonian Telescopes

MEADE.COM

WARNING!

Never use a Meade®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 finder at or near the Sun. Do not look through the telescope or its finder as it is moving.

Children should always

have adult supervision while observing.

WARNING!

Never leave the primary mirror uncovered during the daytime unless using the telescope to view terrestrial objects.

CONTENTS

elescope Features ...................................................... 8

Assembly ........................................................................ 5

Assemble the Base .................................................. 5

Assemble the tube .................................................... 6

t Eyepiece, Attach red dot finder ...................... 7

Inser Collimating the Optical System

Align the red dot finder..............................................11

The deluxe red dot finder ..........................................11

Using a Dobsonian Telescope ..................................11

Calculate Magnification

Observing ......................................................................12

Some Tips ................................................................15

Care of the Optics ....................................................15

Meade Customer Service ..............................................16

Specifications ................................................................17

Optional Accessories......................................................19

............................................12

................................ 8

® The name "Meade" and the Meade logo are trademarks registered with the U.S. Patent and Trademark Office and in principal countries throughout the world. "LightBridge " is a trademark of Meade Instruments Corporation.

Fig. 1 Telescope features.

Tube Assembly

1. Eyepiece

2. Focuser assembly

3. Front OTA (optical tube assembly)

4. Top truss lock knobs (3)

5. Trusses (3)

6. Bottom truss lock knobs (3)

7. Altitude bearing

8. Rear OTA

Inset A: Focuser assembly.

Base Assembly

9. Side base panels (2)

10. Front base panel

11. Circular base plates (2)

12. Feet (3)

Inset A

13. Focus knobs ocus loc

14.

ment knobs

15. 1.25" & 2"eyepiece holder

16. Draw tube

17. Thumbscrew

Inset B

18. Fan

19. Fan battery

pack (inset)

20. Collimation

adjustment screw (3)

21. Collimation

Loc

k & tension adjust

k screw (3)

Inset B: Base of mirror tube.

ASSEMBLY

ASSEMBLE THE BASE

Note: You will need to supply a phillips screwdriver and a one-

ter inch or adjustable wrench to assemble the telescope.

quar Note: Numbers in parentheses. e.g., (9), refer to Fig.1 and Fig. 1

insets

Countersunk depression on this side of base

STEP 1: The base suppor

ts the telescope and allows you to

move the telescope from side to side.

Line up one of the base side panels (9) with the base front panel (10) as shown here. Thread in the two black attachment bolts to secure the panels together. Tighten the bolts to a firm feel.

Repeat with second side panel.

STEP 2: Turn the base panels on their side.

Line up the circular base(11) with the 7 predrilled holes against the panels.

Thread 6 black bolts into the base, as shown here. Make sure that the side with the countersunk holes on the base face the bottom (see photo)

STEP 3:

Slide the center bearing bushing into the 7th (center) hole of the circular base.

Line up the other circular base (sometimes called the ground base), which contains three teflon pads (finger points to a pad) that help the base to move smoothly...

roller bearing

asher

center bearing bushing

STEP 4: ...and place it over the center bearing bushing.

Place a washer over the center bolt.

Place the bolt and washer into the center cylinder.

On the other side of the base, place another washer and an

ut (inset). Tighten the nut to “finger-tight” only

adjustment bolt

attachment n

STEP 3 & 4 DELUXE MODELS ONLY:

Place the center bearing bushing into the countersunk hole of the

round plate. Slide the three roller bearing plates over the center

washers

bearing bushing: First the roller bearing plate, then the roller bearing itself (the plate that looks alike a wagon wheel), then the second roller bearing plate. Place the top part of the base plate assemb

roller

ing

bear plates

the adjustment knob bolt, place two washers on either side of the roller bearing washer. Slide the adjustment bolt through the top base board and into the center bearing bushing and hand-tighten. A nut is captured on the bottom plate. See drawing and photo at left.

ly over the center bearing bushing.To secure in place: On

STEP 5: Next attach the three feet to the bottom panel. Line up

each foot and thread a small attachment screw into the foot to hold it in place. Tighten to a firm feel.

ASSEMBLE THE TUBE

dust cover

seam

front panel

truss knobs

truss

Note: When attaching the feet, make sure that the center countersink depression is on the opposite side of the base

STEP 6: Move the circular panels. They should move easily

about, without any stiffness. If not, tighten or loosen them using a screwdriver while holding the attachment nut in place (with your fingers or a wrench) on the other end of the bolt.

STEP 7: Turn the base so that it is now resting on the feet.

Place the rear OTA (8) into the base. Make sure that the altitude bearings fit snugly into the openings on the side panels of the base. Make sure that the seam of the tube is pointing at the front panel.

Lift to remove the dust cover from the mirror.

STEP 8: Loosen the three bottom truss knobs (6).

Place each truss (5) into a set of slots.

slots

Tighten the truss knobs after all three trusses are in place.

slots

STEP 9: After all 3 trusses are in place, loosen the knob (4) on

top of each truss.

Place the secondary mirror tube (3) into the slots at the top of

each truss....

STEP 10: ...and tighten the truss knobs.

Make sure that the seam on the tube is also pointing towards the front panel (see step 7).

INSERT EYEPIECE AND ATTACH RED DOT FINDER

STEP 10: The entire assembly should move easily up and

down and from side to side.

STEP 11: Insert the one and one quarter inch eyepiece (1) into

ocuser assembly and tighten the focuser thumbscrew (17).

the f To focus the eyepiece, turn the focuser wheels (13) in or out.

If you have the deluxe 2 inch eyepiece, remove the 1.25"

eyepiece holder

holder thumbscrew

eyepiece holder (15) from the focuser assembly by loosening holder thumbscrew (as shown in photo to the left). Slide the 2

yepiece into the focuser and tighten with the eyepiece

inch e

king screw.

loc

ocuser has both a lock knob and a tension adjustment knob.

The f The first lock prevents the draw tube (16) from moving in and out. The second loc locking a focus position into place.

Experiment with these knobs to discover which adjustments are

comfortable with your viewing style.

k locks the focuser knob, thereby

hex screw

top end of slot

thumbscrew

bracket

groove

STEP 12: A red dot finder projects a red dot in place of

crosshairs, to make it easier to line up more precisely with a target.

First, assemble the red dot finder. Slide the bracket over the groove of the red dot finder scope. Tighten the two hex screws with the supplied hex wrench to secure in place.

Slide the red dot finder bracket into the slot on the top OTA. Slide it in from the top (it will only go into the slot from this end). Tighten

ket securely in place.

the thumbscre

w to hold the red dot br

You will need to align the red dot finder. See page 8.

STEP 13: To move the telescope, remove the tube assembly

from the base assembly. Grasp the tube assembly by the trusses and lift up. It is recommended that you relocate the telescope when it is disassembled into two pieces.

STEP 14: Note that there is a fan on the bottom of the mirror

tube. It is powered by a battery pack using 4 AA user-supplied batteries.

ou begin obser

If y heated b “turb

y the sun or b

ulence” your images stabilize and are steady. The fan probably needs to be used less than an hour.

ving at sunset, and the telescope has been

y being in y

our car

, you may notice

in your images. In this case, you can run the fan until

Note also that there are three lock screws and three collimation scre

These scre

ws are f

or use with the collimation procedure.

See page 14.

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