Omegon Advanced X 152 DOB User manual

Instructions Manual
Omegon® Advanced X 152 DOB
Omegon® Advanced X 203 DOB
Omegon® Advanced X 254 DOB
Omegon® Advanced X 304 DOB
English version 7.2023 Rev. B, Art.-Nr. 53802, 53803, 53804, 79799

The Omegon® Advanced X
Series
Congratulations on the purchase of one of the
new Omegon® Advanced X Series telescope. This
telescope will give you hours of fun, with its
optical precision polished mirrors and huge light
gathering capability; it is the ideal companion for
the beginner or intermediate amateur. It’s simple
design and optical quality makes the Advanced X
one of the most exciting Dobson telescopes you
will ever find in the market.
1. What’s included? The telescope is shipped in
two boxes. The tube box and the base box. To
keep box volume to a minimum, the base is
supplied disassembled. To assemble the base you
only need a screw driver (Philips-type) –not
supplied. Assembly takes about 20 minutes and
all supplied parts and ware are easily put
together. Below you can see the included base
parts and ware. Please take a few minutes to
familiarize yourself with it.
Telescope base parts
1. Disc (top); 7. Handle & screws;
2. Disc (bottom); 8. Feet & screws;
3. Side panel (right); 9. Side friction kit;
4. Front panel; 10. Wood screws;
5. Side panel (left); 11. Azimuth friction kit.
6. Eyepiece Rack & screws;
2. Assembling the telescope base. The telescope
base is shipped in a flat cardboard box. Please
provide a clean and flat surface where you can lay
the parts and enough space to assemble it.
2.1. Step 1 - Assembling the side and front
panels. Identify parts #3, #4 and #5. Used the
supplied Allen wrench and 4x of the wood screws
#10. Please notice that the side panels #3 and #5
are slightly different. Panel #5 has two additional
holes to fix the eyepiece rack #6. The front panel
#4 has two sides. Make sure that the metal
washers are not visible from the outside. When
Step 1 is finished make sure that the side panel
(right) #3 is on the right side of this assembly and
the front panel washer (plated) do not show to
the outside - marked with arrows - below.
These instructions apply to telescopes of different sizes. Therefore, the
parts may have slightly different proportions than shown above.

2.2. Step 2 –Fixing the Disc (top). Please use
another 6x wood screws #10. Use the Allen
wrench to tighten the screws. Please notice that
the Disc (top) #1 has two sides. A side with
circles cut in the wood’s surface to hide the
screw heads. Tighten the screws from this side.
2.3. Step 3 –Setting the feet to the Disc
(bottom). Before proceeding with the assembly,
set the 3x feet and screws #8 to the Disc
(bottom) #2. Make sure to fix the feet to the
side where the metal nut is flush to the disc’s
surface (arrow below). It is important to identify
and fix the feet to the correct side.
Solar Warning! Do not point the telescope to the Sun, concentrated light will
cause irreversible eye damage and even blindness!
Figure 1. Exploded view of the complete assembly.

2.5. Step 5 –Fixing the Disc (bottom) #2 to the pre-assembled wood parts. Please proceed as shown. The handknob
allows adjusting pressure to the Teflon© pads increasing/decreasing friction.
Did you know? The Hand knob
adjusts the friction of the azimuth
movement. If you feel that the
movement on this axis is too
smooth, just give a quarter of turn
and tighten the central hand knob.
This will visibly increase the friction
making the movement stiffer. If on
the contrary the movement is too
stiff release the hand knob for a
smoother movement.
2.6. Step 6 –Setting the Handle #7 and
eyepiece rack #6. Use the supplied screws to
fix both the Handle and eyepiece rack as
shown in figure 1 and figure 2.
The one time assembly of the telescope base
is now completed. It can be easily carried with one hand using the handle. The
eyepiece rack can be used to store eyepieces and Barlow (not included) during
observations.
The optical tube is the other main part of this telescope. It already comes pre-
assembled. Its side bearings sit on the base’s Teflon© pads. Depending on the
weight of eyepiece, Barlow or finderscope the tube may tilt to the front or the back
during observation. To avoid this inconvenient problem we have included a unique
side friction kit #12 that allows increasing the friction between the Teflon pads and
the side bearings. Please look at the main features of the optical tube and how to
assemble the side friction kit #12.
3. The optical tube. Please look at the main features of the optical tube in the figure
below.
Optical tube features
A –Side bearing B –Focuser C –Finderscope base
A dust cap for the front aperture and for the focuser are also included. Please make sure to use it to protect the telescope
from dust and humidity. The telescope should always be stored in a clean and dry place.
Figure 2.

3.1. Installing the optical tube to the telescope base.
The tube fits to the assembled base as shown. For convenient
transportation, both tube and base should set apart after each
observation.
3.2. Installing the side friction kit. To increase the friction on the tube
bearings a system of tensioning springs is used. This avoids the
inconvenient tilt of unbalanced telescope tubes.
Please identify the different components and assemble it as shown. Make
sure to loop the cord through one hook of the spring.
3.3.
3.3. Installing the Finderscope. Start by sliding the supplied O-ring to the tube mark
(arrow below). Next, slide the finderscope bracket and use the thumbscrew to
tighten it in place. The finderscope tube can be fitted to the finderscope bracket.
Make sure that the adjustment screws sit on the finderscope tube recess and the O-
Ring on the front.
How to use the tension spring? Pass one hook #G to the nylon
cylinder #I and use the locking knob #F to fix it in place. The spring will
be lose. The opposite spring loop should be laced with the cord E.
Stretch the spring pulling the loop and fitting it the other nylon
cylinder #D. Do this to both side bearings.

Specifications
152/1200
203/1200
254/1250
304/1500
Aperture
152 mm
203 mm
254 mm
304 mm
Focal length
1200 mm
1200 mm
1250 mm
1500 mm
Focal ratio
f/8
f/6
F/4,9
F/4,9
Finderscope
6 x 30
8 x 50
8 x 50
8 x 50
Focuser
Crayford 2"
Eyepiece rack
yes
Accessories included
35 mm extender, 2"/1,25" adapter, 25 mm Ploessel eyepiece