Meade instruction manual Telescope Specifications, Specifications ETX-90EC Astro Telescope

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TELESCOPE SPECIFICATIONS

Specifications: ETX-90EC Astro Telescope

Optical design	. . . . . Maksutov-Cassegrain
Primary mirror diameter		. . . . . 96mm (3.78”)
Clear aperture		. . . . . . 90mm (3.5”)
Focal length	. . . . . . .	. . . . . . . . 1250mm
Focal ratio (photographic speed)		. . . . . . . . . . . f/13.8
Near focus (approx)		. . . . . 11.5 ft (3.5m)
Resolving power		. . . . . . 1.3 arc secs
Super multi-coatings (EMC). . . .	. . . . . . .	. . . . . . . . standard
Limiting visual stellar magnitude (approx.).		. . . . . . . . . . . 11.7
Image scale	. . . . . . .	. . . . . . . 1.16°/inch
Maximum practical visual power	. . . . . . .	. . . . . . . . . . . 325X
Optical tube dimensions
(dia. x length)	10.4cm x 27.9cm (4.1” x 11”)
Eyepiece	. . . . . . .	Super Plössl 26mm
Viewfinder	. . . . . . .	. . . . . . . 8 x 21mm

Secondary mirror obstruction (dia.; %) . . 27.9mm (1.1”); 9.6%

Telescope mounting		. . . . . fork type; double tine
Setting circle diameters		. . . . . . . . Dec: 3.5”; RA: 7”
Input voltage	. . . . . . . . .	. . . . . . . . . . . . 12 volts DC
Motor DriveSystem	DCservo motors with encoders, both axes
Slow-Motion Controls	. . . . . . . . .	electric, 4 speed, both axes
Optional Autostar Capability		. . . . . . . . . . . . . . . . . . yes
Hemispheres of operation		North and South, switchable
Bearings:
Altitude		. . . . . UHMW polyethylene
Azimuth	. . . . . . . . .	. . . . . . . . . . . . . . . . . PTFE
Materials:
Tube body . . . .	. . . . . . . . .	. . . . . . . . . . . . . . aluminum
Mounting	. high-impact ABS, aluminum-reinforced
Primary mirror		. . . . . . . . . . . Pyrex® glass
Correcting lens		BK7 optical glass, Grade-A
Telescope dimensions:
. . . . . . . . . . . . .	. . . 38cm x 18cm x 22cm (15” x 7” x 9”)

Telescope net weight:
(incl. Electronic Controller & batteries)	. . 3.5kg (7.8 lbs)
Telescope shipping weight	. 5.8kg (12.8 lbs)
Battery Life (approx.):
with Electronic Controller	. . . . . . . . 45 hrs
with Autostar	. . . . . . . . 20 hrs

Specifications: ETX-125EC Astro Telescope

Optical design . . . . . . . . . . . . . . . . . . . Maksutov-Cassegrain Primary mirror diameter . . . . . . . . . . . . . . . . . 138mm (5.43”) Clear aperture . . . . . . . . . . . . . . . . . . . . . . . . . 127mm (5.0”) Focal length . . . . . . . . . . . . . . . . . . . . . . . . . 1900mm (74.8”) Focal ratio (photographic speed) . . . . . . . . . . . . . . . . . . . f/15 Near focus (approx). . . . . . . . . . . . . . . . . . . . . . . 5.5m (18 ft) Resolving power. . . . . . . . . . . . . . . . . . . . . . . . . 0.9 arc secs Super multi-coatings (EMC). . . . . . . . . . . . . . . . . . . standard Limiting visual stellar magnitude (approx.). . . . . . . . . . . . 12.5 Image scale. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.76°/inch Maximum practical visual power . . . . . . . . . . . . . . . . . . 500X Optical tube dimensions

(dia. x length) . . . . . . . . . 14.6cm x 36cm (5.75” x 14.2”) Eyepiece. . . . . . . . . . . . . . . . . . . . . . . . . Super Plössl 26mm Viewfinder. . . . . . . . . . . . . . . . . . . . . . . 8 x 25mm right-angle Secondary mirror obstruction (dia.; %). . 39.4mm (1.6”); 9.6% Telescope mounting . . . . . . . . . . . . . . . fork type; double tine Setting circle diameters. . . . . . . . . . . . . . . . Dec: 4.3”; RA: 9” Input voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 volts DC Motor Drive System . . DCservo motors with encoders, both axes Slow-Motion Controls . . . . . . . . . electric, 4 speed, both axes Optional Autostar Capability. . . . . . . . . . . . . . . . . . . . . . . yes Hemispheres of operation . . . . . North and South, switchable Bearings:

Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Acetal Azimuth . . . . . . . . . . . . . . . . . . . . . . . radial ball bearing

Materials:

Tube body . . . . . . . . . . . . . . . . . . . . . . . . . . . aluminum Mounting . . . . . . . . . . high-impact ABS, zinc-reinforced Primary mirror . . . . . . . . . . . . . . . . . . . . . . Pyrex® glass Correcting lens. . . . . . . . . . . BK7 optical glass, Grade-A

Telescope dimensions:

. . . . . . . . . . 48cm x 23cm x 27cm (19” x 8.9” x 10.8”)

Telescope net weight:

(incl. Electronic Controller & batteries) . . 7.9kg (17.4 lbs) Telescope shipping weight. . . . . . . . . . . . . . 12.4kg (27.4 lbs) Battery Life (approx.):

with Electronic Controller . . . . . . . . . . . . . . . . . . . 45 hrs with Autostar . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 hrs

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