Meade Infinity 76 User Manual

MEADE INFINITY 76 USER’S GUIDE

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

at or near the Sun. Do not look through the telescope or viewnder

as it is moving. Children should always have adult supervision while
observing.

INTRODUCTION

Your telescope is an excellent beginner’s instrument and is designed to ob­serve objects in the night sky and also on land. It can be your personal win­dow on the universe or allow you to intimately study the behavior of nesting
birds on a distant hillside. The telescope is shipped with the following parts:

ASSEMBLY

The tripod is the basic support for your telescope and comes pre-assem­bled from the factory; except for the accessory tray. In order to use the
scope a small amount of assembly is required. Follow the below steps to
assemble the telescope.

Note: Number in brackets, e.g., (3), refer to the item numbers in Fig. A.

1. To setup the tripod, spread the legs out evenly and place on solid
ground. Loosen the leg lock knobs and extend the inner legs to de­sired height. Do this for each leg until the top of the tripod is approxi­mately level. Re-lock the leg lock knob.

2. Attach the accessory tray to the tripod by threading it into the center
nut between the tripod legs.

ATTACHING THE OPTICAL TUBE ASSEMBLY (OTA)

1. Remove the two lock knobs (2) from the optical tube mount.

2. Slide the Slow-motion control rod (8) into the slow-motion control lock
knob hole (9).

3. Place the optical tube (1) between the forks of the mount, oriented as
shown.

4. Thread a lock knobs (2) through each of the holes in the forks of the

mount and tighten to a rm feel.

ATTACHING THE RED-DOT FINDER

A viewnder (4) has a wider eld of view, which makes it easier to locate
objects. The viewnder has a red dot to make it easier to line up more pre-

cisely with a target.

1. Note the two thumbscrews threaded onto two bolts (see Fig. C) on the
optical tube. Remove the thumbscrews from the tube.

2. Line up the two holes on the viewnder bracket over the two bolts.
Slide the bracket over the bolts. See Fig. C.

3. Replace the thumbscrews onto the bolts and tighten to a rm feel.

REMOVING THE DUST COVERS

1. Remove dust covers(6) at the front of the scope by pulling the cover
away from the telescope.

2. Remove the dustcover from the focuser by pulling it out of the focuser
drawtube.

INSERTING THE EYEPIECE

1. Slide the 20mm eyepiece (4) into focuser drawtube.

2. Tighten thumbscrew to hold the eyepiece in place.

ALIGNING THE RED-DOT FINDER

Perform the rst part of this procedure during the daytime and the last step

at night.

1. Point the telescope at an easy- to-nd land object such as the top of a
telephone pole or a distant mountain or tower. Look through the eye­piece and turn the focuser knob (3) until the image is sharply focused.

Center the object precisely in the eyepiece’s eld of view.

2. Turn on the red-dot viewnder by rotating the large knob under the
viewnder lens clockwise (see Fig. C). Turn the knob to adjust the

intensity of the red dot as desired.

3. Look through the viewnder. Turn one or both of the viewnder’s align-
ment screws (see Fig. C) until the red-dot is precisely over the same
object as you centered in the eyepiece.

4. Check this alignment at night on a celestial object, such as the Moon

or a bright star, and use the viewnder’s alignment screws to make
any necessary renements.

5. When nished, turn off the viewnder by turning the large knob under
the viewnder lens counter- clockwise until it clicks.

MOVING THE TELESCOPE

Your telescope is alt-azimuth mounted. Alt-azimuth is just a complicated
way of saying that your telescope moves up and down and from side to
side. Other telescopes may be mounted in different ways.

1. Slightly loosen both of the star-shaped vertical control knobs (2) and
slow-motion rod lock knob (9). Loosening these knobs allow you to
move the telescope up and down.

2. Slightly loosen the horizontal lock knob (10). Loosening this lock al­lows the telescope to be moved from side to side.

3. Once an object is found, re-tighten the control knobs. You can then
turn the slow motion control knurled knob(8) to make smooth and pre­cise movements as you can follow (or “track”) an object vertically as it
moves in the eyepiece.

4. To use the slow motion control feature (8) aim the telescope at an
object and tighten the control knobs (2,9). Then lock the altitude lock
knob (2) and rotate the slow motion control (8) to follow the target in
the vertical direction.

A NOTE ABOUT THE TELESCOPE

The Meade 76mm reecting telescope uses mirrors to achieve focus and

is designed primarily for night-sky viewing where image orientation is not
important. However when looking at daytime objects often image orienta­tion is important. For daytime terrestrial use, Meade has included a 20mm
erect-image eyepiece for correcting the image orientation. Please note the
included 9mm eyepiece does not have this feature and objects will not be
correctly orientated. This is normal. When locating objects always start with

the 20mm erect-image eyepiece as it has a larger viewing eld.

1. Optical Tube Assem-

bly (OTA)

2. Vertical Motion Lock

Knob

3. Focusing Knob

4. Red-dot Viewnder

5. Eyepiece

6. Front Dust Cap

7. Secondary Mirror

Alignment Screws

8. Slow-Motion Control

Rod

9. Slow-Motion Control

Lock Knob

10. Horizontal motion

lock knob

11. Tripod leg locks

12. Accessory tray

13. Tripod legs

14. Primary Mirror Align-

ment Screws

• 76mm Optical tube

• Red Dot nder

• Yoke-style mount

• Software disk

• Aluminum tripod with ac-

cessory tray

• Two 1.25” Eyepieces:

20mm Erect-Image, H9mm

• Cell phone holder

• Carry bag

• Instruction sheet

Figure A

(not shown)

(not shown)

Lock
knob

Slide
rod
through
hole

Place
tube
between
forks

Lock
knob

Lock
knob

Figure B

Figure D

Figure C

Adjustment
knobs

Thumbscrew

Mounting

knobs

On/Off

CARING FOR YOUR TELESCOPE

Your telescope is a precision optical instrument designed for a lifetime of
rewarding viewing. It will rarely, if ever, require factory servicing or mainte­nance. Follow these guidelines to keep your telescope in the best condition:

Avoid cleaning the telescope’s optics. A little dust on the mirror or lens sur­faces of the telescope will not cause loss of image quality. When absolutely
necessary, dust on the lens or mirrors should be removed with very gentle
strokes of a camel hair brush or blown off with an ear syringe (available at
most pharmacies).

Fingerprints and organic materials on the optics may be removed with a
solution of 3 parts distilled water to 1 part isopropyl alcohol. You may also
add 1 drop of biodegradable dish washing soap per pint of solution. Use
soft, white facial tissues and make short, gentle strokes. Change tissues
often. CAUTION: Do not use scented or lotioned tissues or damage could
result to the optics. DO NOT use a commercial photographic lens cleaner.

COLLIMATION (ALIGNMENT) OF OPTICS

All Meade reecting 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 rst 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.

1. CORRECT COLLIMATION

The properly collimated (aligned) mirror system in the Meade telescope
assures the sharpest images possible. This occurs when the primary mir­ror and secondary mirror are tilted so that the focused image falls directly
through the center of the focuser draw tube. These mirror tilt adjustments
are made with the secondary mirror assembly and the primary mirror cell
(Fig. E,F,G) and will be discussed later.
To inspect the view of the mirror collimation, look down the focuser draw
tube with the eyepiece removed. The edge of the focuser drawtube (1, Fig.

H), will frame the reections of the primary mirror with the 3 mirror clips (2,

Fig. H), the secondary mirror (3, Fig. H), the spider vanes (4, Fig. H), and

your eye (5, Fig. H). Properly aligned, all of these reections will appear

concentric (i.e., centered) as illustrated in Fig. H. Any deviation from the
concentric reections will require adjustments to the secondary mirror as­sembly and/or the primary mirror cell (Fig. F,G).

2. SECONDARY MIRROR HOLDER ADJUSTMENTS

If the secondary mirror (1, Fig. I) is centered in the draw tube (2, Fig. I), but

the primary mirror is only partially visible in the reection (3, Fig. I), one or

more of the 3 secondary mirror collimation screws need adjusting. First, un­thread each of the secondary mirror collimation screws slightly to the point
of where you can tilt the secondary holder from side-to-side. By grasping
the secondary holder with your hand, tilt the secondary mirror holder until
you see the primary mirror become as centered in the reection of the di­agonal mirror as possible. Once you are at the best position, thread in the
3 secondary mirror collimation screws to lock the holder in place. Then, if

necessary, make adjustments to these 3 screws to rene the tilt-angle of

the secondary mirror until the entire primary mirror can be seen centered
within the secondary mirror reection. When the secondary mirror is cor­rectly aligned, it will look like Fig. J (Note: The primary mirror is shown out
of alignment).

3. PRIMARY MIRROR ADJUSTMENTS

If the secondary mirror (1, Fig. J) and the reection of the primary mirror (2,
Fig. J) appear centered within the draw tube (3, Fig. J), but the reection
of your eye and the reection of the secondary mirror (4, Fig. J) appear off

center, you will need to adjust the primary mirror tilt screws of the prima­ry mirror cell (2, Fig. G). These primary tilt screws are located behind the
primary mirror, at the lower end of the main tube. The long screws lock the
mirror in place where the shorter screws perform the adjustment.

To adjust the primary mirror tilt screws (2, Fig G), rst turn by several turns,

the primary mirror cell lock knobs (3, Fig. G) that are next to each primary
mirror tilt screw. The three primary mirror cell locking screws are Phillips
head screws and are longer than the adjustment screws.
Then by trial-and-error, turn the short primary mirror tilt screws (2, Fig. G)
until you develop a feel for which way to turn each knob to center the reec­tion of your eye. Once centered, as in Fig. H, turn the 3 long primary mirror
cell locking screws (3, Fig. G) lightly to re-lock the tilt-angle adjustment.

4. STAR TESTING THE COLLIMATION

With the collimation performed, you will want to test the accuracy of the
alignment on a star. Use the 20mm eyepiece and point the telescope at
a moderately bright (second or third magnitude) star, then center the star

image in the telescope’s eld-of-view. With the star centered follow the

method below:

• Bring the star image slowly out of focus until one or more rings are visi-

ble around the central disc. If the collimation was performed correctly, the
central star disk and rings will be concentric circles, with a dark spot dead
center within the out-of-focus star disk (this is the shadow of the secondary
mirror), as shown in Fig. K3. (An improperly aligned telescope will reveal
elongated circles (Fig. K1), with an off-center dark shadow.)

•If the out-of-focus star disk appears elongated (Fig. K1), you will need to

adjust the primary mirror adjusting tilt screws of the primary mirror cell (3,
Fig. G)

•To adjust the primary mirror tilt screws (3, Fig. G), rst unscrew several

turns the 3 hex-head primary mirror cell locking screws (2, Fig. G), to allow
free turning movement of the tilt knobs.

•Using the exible cable controls move the telescope until the star image is

at the edge of the eld-of-view in the eyepiece, as in Fig. K2.

•As you make adjustments to the primary mirror tilt screws (3, Fig. G), you

will notice that the out-of-focus star disk image will move across the eye-

piece eld. Choose one of the 3 primary mirror tilt screws and slightly move

the shadow to the center of the disk. Then slightly move the telescope using

the exible cable controls to center the star disk image in the center of the

eyepiece.

• If any further adjustments are necessary, repeat this process as many

times as needed until the out-of-focus star disk appears as in Fig. K3, when

the star disk image is in the center of the eyepiece eld.

• With the star testing of the collimation complete, tighten the 3 hex-head

primary mirror locking screws (2, Fig. G)

CHANGING THE VIEWFINDER BATTERY

If the viewnder red dot does not illuminate, verify the viewnder is on by ro­tating the knob below the viewnder lens clockwise. If the red dot does not

illuminate, the battery may need replacing. To replace the battery, press the

left side of the viewnder housing labeled “push”. The battery compartment
will slide out on the right side of the viewnder (see Fig. L). Replace the

battery with a Lithium CR-2032 battery with the positive side up. Then push

the battery compartment back into the viewnder and power on.

MEADE LIMITED WARRANTY

Every Meade telescope and telescope accessory is warranted by Meade
Instruments Corp (“Meade”) to be free of defects in materials and work­manship for a period of ONE YEAR from the date of original purchase in
the U.S.A. Meade will repair or replace a product, or part thereof, found by
Meade to be defective, provided the defective part is returned to Meade,
freight-prepaid, with proof of purchase. This warranty applies to the original
purchaser only and is non-transferable. Meade products purchased out­side North America are not included in this warranty, but are covered under
separate warranties issued by Meade international distributors. RGA Num­ber Required: Prior to the return of any product or part, a Return Goods
Authorization (RGA) number must be obtained from Meade by writing, or
by calling [phone]. Each returned part or product must include a
written statement detailing the nature of the claimed defect, as well as the
owner’s name, address, and phone number. This warranty is not valid in
cases where the product has been abused or mishandled, where unautho­rized repairs have been attempted or performed, or where depreciation of

the product is due to normal wear-and-tear. Meade specically disclaims
special, indirect, or consequential damages or lost prot which may result

from a breach of this warranty. Any implied warranties which cannot be
disclaimed are hereby limited to a term of one year from the date of original

retail purchase. This warranty gives you specic rights. You may have other

rights which vary from state to state. Meade reserves the right to change
product specications or to discontinue products without notice. This war­ranty supersedes all previous Meade product warranties.

VISIT MEADE.COM FOR MORE INFORMATION!

CR-2032

battery

Battery

compartment

Figure L

Push here to
open battery
compartment

3

2

4

5

3

3

1

2

2

2

1

3

1

2

4

5

3

3

1

2

2

2

2

1

3

4

1

Figure E

Figure F

Figure I

Figure H

Figure G

Figure K

Figure J

1

3

2

Meade Instruments Corp. 27 Hubble, Irvine, CA. 92618, USA REV0. 20160606