To utilize all the features of the telescope, it is necessary to enter some
information into the telescope's computer memory, and learn the menu structure
of the Keypad hand controller, described later in this manual.
As advanced as LX200 electronics are, the telescope is very straightforward
to operate even if you have no experience whatsoever in using a personal
|IMPORTANT NOTICE! Never use a telescope or spotting scope to look at the Sun! Observing the Sun, even for the shortest fraction of a second, will cause irreversible damage to your eye as well as physical damage to the telescope or spotting scope itself. |
If you are reading this manual for the first time and are anxious to "look
through the telescope," this section will describe how to use the telescope
without going through the rest of the manual. But be sure to come back and
read the details, for most of the telescope's features can not be accessed
without a full knowledge of these details.
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1. Using the LX200 Manually
The easiest way to use the telescope is to operate it manually. With
the telescope mounted on the Field Tripod, and with the diagonal prism and
eyepiece in place, you are ready to make observations through the telescope.
Even without the viewfinder (if not yet installed), terrestrial objects
will be fairly easy to locate and center in the telescope's field of view
using a low power eyepiece and "gun sighting" along the
side of the main telescope tube.
By unlocking the R.A. Lock (7, Fig. 3), the
telescope may be turned rapidly through wide angles in Right Ascension (R.A.).
The reason for the terminology "Right Ascension" and its complementary
term, "Declination" will be made clear further on in this manual.
For now, "Right Ascension" simply means "horizontal"
and "Declination" means "vertical". Fine adjustments
in R.A. are made by turning the R.A. Slow-Motion Control Knob (8, Fig. 3),
while the R.A. lock is in the "unlocked" position.
DO NOT ATTEMPT TO MOVE THE TELESCOPE MANUALLY IN A HORIZONTAL DIRECTION
WHEN THE R.A. LOCK IS IN THE "LOCKED" POSITION.
The R.A. Slow-Motion Control Knob may be turned, if desired, with the
R.A. Lock in a "partially locked" position. In this way, a comfortable
"drag" in R.A. is created. But do not attempt to operate
the R.A. Slow-Motion Control Knob with the telescope fully locked in R.A.,
as such operation may result in damage to the internal gear system.
Releasing the Declination Lock Knob (2, Fig. 4), permits sweeping the telescope
rapidly through wide angles in Declination.
To use the Declination fine-adjust, or Manual Slow-Motion Knob, lock the
telescope in Declination using the Declination Lock Knob (2, Fig. 4), and
turn the Declination Slow-Motion Knob (1, Fig. 4).
With the above mechanical operations in mind, select an easy to find terrestrial
object as your first telescope subject—for example, a house or building
perhaps one-half mile distant.
Unlock the Declination Lock Knob (2, Fig. 4), and R.A. Lock (7, Fig. 3),
center the object in the telescopic field of view and then re-lock the Dec.
and R.A. locks. Precise image centering is accomplished by using the Dec.
and R.A. slow motion controls.
The Focus Knob (5, Fig. 3) is located at the "4 o'clock" position
as you face the rear cell of the telescope. Focusing is accomplished internally
by a precise motion of the telescope primary mirror so that, as you turn
the focus knob, there are no externally moving parts. You will find that
if you turn the focus knob counter-clockwise you are focusing towards the
infinity setting, and turning clockwise is for close distance. There are
about 45 complete turns to go from one end of focus to the other, and it
is possible to focus past infinity. Be patient during focusing as images
quickly go in and out of focus with only a slight amount of turning of the
Before using the telescope manually during the daytime, be sure to read
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2. Using the LX200 In Land
The 7", 8", 10", and 12" LX200 telescopes are shipped
with the microprocessor set to Land, the align menu option you will wish
to use to view terrestrial objects. In this menu option 4 different motion
speeds are active, allowing the telescope to be moved electronically by
means of the Keypad. To use the telescope in Land, follow these steps.
1. Loosen the Dec. Lock Knob (2, Fig. 4) and position the optical tube assembly
approximately level, so that the Dec. Circle (3, Fig. 3) reads 0°.
Retighten the Dec. Lock Knob.
2. Loosen the R.A. Lock (7, Fig. 3) and rotate the telescope so that the
R.A. Pointer (9, Fig. 3) and the Hour Angle (HA) Pointer (16, Fig. 3) are
approximately in line with each other. This will position the fork arms
so that they are parallel to the Power Panel (11, Fig. 3). Tighten the R.A.
The above two steps are not necessary for the telescope to work, so don't
worry about having to get it exactly right. The telescope has some "illegal"
positions, places where the telescope will not go and these two steps insure
3. After setting up the telescope, plug in both coil cords with the Keypad,
one of the supplied power sources, either the AC Wall Adapter Power Converter
(for AC current wall outlets), or the optional DC Cigarette Lighter Power
Cord (used in an automobile's cigarette lighter outlet, with the ignition
turned on only to allow the electric power on from the car battery).
4. Turn on the power switch on the Power Panel of the LX200. The Keypad
Display (1, Fig. 5) will show "MEADE" for several seconds as the
microprocessor does a self-diagnostic test. When the self-diagnostic test
is complete, the display will show "TELESCOPE" on the top line,
"OBJECT LIBRARY" on the lower line, and the red LED light next
to the "SLEW" button will light up.
5. At this point, the LX200 is ready to use. Select the speed at which you
want to move the telescope by pressing the appropriate Speed Selection Key
(4, Fig. 5). Note that you will be able to "see" the telescope
move only in the SLEW and FIND modes; CNTR (center) and GUIDE motions can
only be seen while looking through the telescope. The red LED next to that
key (3, Fig. 5) will light, indicating the speed selected. Then press one
of the four direction keys (2, Fig. 5) to move the telescope in that direction
at the selected speed.
The LX200 can also be moved manually with the R.A. and Dec. locks released,
or as described above only. The Declination Manual Slow-Motion Knob (1,
Fig.4) is non-functional when power is supplied
to the telescope. When the power is "On", only use the N, S, E,
and W keys on the Keypad Hand Controller. Serious damage can occur to
the internal gears of the motor assembly if the Declination Manual Slow-Motion
Knob is turned even a slight amount by hand.
Before using the telescope during the daytime, be sure to read "Daytime
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3. Using the LX200 In Altazimuth (ALTAZ)
The two quick start methods described above allow you to use the telescope,
but do not make use of any of the computer features available, including
finding objects from the Object Library and automatic tracking of stars.
In order for these features to work, the telescope's power needs to be "On",
and the computer needs some basic information, which is entered through
the Keypad. Once entered, the information is permanently remembered by the
telescope's computer and need never be entered again, even if the telescope
is turned "On" and "off" many times.
This section will explain what keys to push to get the minimum data required
into the computer, without any detailed explanation. Later, see Section
G, LX200 Modes for detailed instructions. These steps will only take a few
minutes and will allow you to begin making use of all the LX200 features.
Note also, much of this information can be skipped if using the UNKNOWN
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a. Entering Basic Information
In order for the LX200 to make the conversions between the stellar coordinate
system (R.A. and Declination) and the Altazimuth coordinate system (Altitude
and Azimuth), it needs to know three pieces of information. This information
only needs to be entered one time—the LX200 remembers the data even when
the power is off.
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1) Latitude and Longitude of the Observing Site.
NOTE: The SITE information cannot be entered if the telescope is in LAND
mode. If the telescope is in LAND mode, the SITE menu option (Display
2, below) will appear in lower case letters. Follow steps 4-8 to change
the telescope's operation to Altazimuth (ALTAZ) mode before proceeding.
You should find the position of your observing site to within 1 or 2 minutes
of arc in both latitude and longitude. Many automobile, pilot, and topographical
maps, as well as most atlases show latitude and longitude in 15 minute increments
or better. The accuracy of the LX200 will depend on how close you get, so
take a little time to get as accurate as you can.
Once the above information is determined, it can be entered into the telescope.
It is easiest to enter the data with the telescope sitting on a table indoors do
not try to do it outside at night.
Each step below is given without any details or explanations to keep the
process as simple and fast as possible.
As an example, we will enter the data for Costa Mesa, CA (LAT=33°35',
LONG=117°42'). If at any time you get "lost," simply turn
off the telescope and restart this procedure.
1. Turn the telescope on. After a few seconds (after the self-diagnostic
test is complete), the display will look like Display 1.
2. Press the ENTER key. This selects the TELESCOPE functions. The display
should look like Display 2.
3. Press the ENTER key. This selects the SITE functions. The display should
look like Display 3.
4. Press and Hold the ENTER key until the Keypad Hand Controller
beeps. This selects the first site for editing. The display should look
like Display 4, with the first "A" flashing.
5. Press the ENTER key. The display should look like Display 5.
6. Use the number keys to enter your Latitude. The underline designates
the current cursor position. Mistakes can be corrected by moving back (using
the "E" and "W" keys). A negative latitude can be entered
by positioning the cursor under the "+" and hitting the "NEXT"
key (lower right-hand key). When the Latitude is correct, press ENTER. The
display will look like Display 6.
7. Use the number keys to enter your Longitude as above. When complete,
the display will look like Display 7.
8. Press ENTER to complete the site information input. The display will
go back to Display 3.
9. Press MODE to go back to Display 2.
10. Press MODE again to go back to Display 1.
It is important to note that the longitude standard used in the LX200 starts
at 0° in Greenwich, U.K. and increases Westerly only to 359°
59mins. Many maps will show Easterly longitudes which cannot be entered
into the Keypad Display. As an example, if your map indicates that you are
at an Easterly longitude of 18° 27mins, then you would enter
Do not be concerned with differences in longitude and latitude as they
pertain to different map spheroid projections, those minor differences are
too small to adversely affect the longitude and latitude data input.
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2) Local Time and Date.
The local time should be set as accurately as possible, using the 24 hour
format. The local time and date are used to determine sidereal time (star
time) and the pointing accuracy of the telescope will depend on the accuracy
of the time entered. Choose a reliable source as a reference for accurate
time such as your local airport, or telephone company. In the U.S.A. you
can double check the accuracy of the exact minutes by dialing WWV for the
universal coordinated time at (303) 499-7111 (be sure to enter your local
time hour information, not the U.T. hour). For the example, we will use
4:25:00 P.M. on Jan. 15, 1992.
1. The display should look like Display 1. If it does not, press the MODE
key until it does.
2. Press the MODE key twice. The display will look like Display 8, but with
a random LOCAL and SIDE times.
3. Press and HOLD the ENTER key until the Keypad Hand Controller beeps (display
like Display 9).
4. Using the number keys, enter the current local time to within 5 seconds.
(Remember, 4:25:00 P.M. is 16:25:00 in the 24 hour format.) Corrections
can be made by moving the flashing cursor using the W and E keys. The display
should look like Display 10.
5. Press the ENTER key when the time is correct. The display will change
to Display 11.
The next step is to enter the Greenwich Mean Time (GMT) time zone shift.
(This procedure is a lot easier than it sounds.) For users in the U.S.A., refer to the table below to find the GMT time zone shift.
U.S.A. Time Zones
|Daylight Savings Time
Use the top row during Standard Time and the bottom row during
Daylight Savings Time.
For example: In the Pacific Time Zone during Daylight Savings
Time, the GMT time zone shift is +7 hours.
6. Use the number keys to enter the GMT time zone shift. Press ENTER when done; the display will go back to Display 8. If using the LX200 East of Greenwich U.K., enter
a - (minus) GMT time zone shift by moving the blinking cursor backwards
in the display with the W key, then press the NEXT key. The + (plus)
sign will change to - (minus). Use the number keys to enter the
GMT time zone shift.
7. Press the ENTER key. This will select the DATE display (Display 12),
with a random date showing.
8. Press and Hold the ENTER key until the Keypad Hand Controller
beeps. The display will look like Display 13, with the blinking cursor over
the first number.
9. Use the number keys to enter the current date. The display should look
like Display 14. Use the W and E keys to move the blinking cursor left and
right to correct any mistakes.
10. Press the ENTER key when the date is correct.
After you press the ENTER key, the Keypad Hand Controller will display "Updating
planetary data". The position of the planets depends on the date,
so anytime the date is changed, the planet positions are recalculated.
This is all the information the LX200 needs to make use of all features.
The next steps actually align the telescope with the night sky.
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b. Setting Up the Telescope
After the basic information has been entered into the telescope, the telescope
is ready to actually set-up and use. Follow Section A: Telescope Assembly
to setup the telescope outside, and follow these steps:
1. Using the Bubble Level (15, Fig. 3) located on the telescope's drive
base, level the telescope. Position the drive base so that the power panel
faces North (i.e. to view the power panel, you must face South.)
2. Loosen the Dec. Lock Knob (2, Fig. 4 ) and position the optical tube
assembly approximately level (so that the Dec. Circle (3, Fig. 3) reads
0°. Retighten the Dec. Lock Knob.
3. Loosen the R.A. Lock (7 Fig. 3) and rotate the telescope so that the
R.A. Pointer (9, Fig. 3) and the Hour Angle (HA) Pointer (16, Fig. 3) are
approximately in line with each other. This will position the fork arms
so that they are parallel to the Power Panel (11, Fig. 3). Lock the R.A.
Steps 2 and 3 above, are not necessary for the telescope to work, so
don't worry about having to get it exactly right. The telescope has some
"illegal" positions (places where the telescope will not go) and
these two steps ensure proper operation.
4. Turn the telescope on. After a few seconds (after the self-diagnostic
test is complete), the display will look like Display 15.
5. Press the ENTER key. This selects the TELESCOPE functions. The display
should look like Display 16.
6. Press the NEXT key. This will move the arrow to the lower line (see Display
7. Press the ENTER key to select the ALIGN function. The display will look
like Display 18. (If the display looks like Display 19 - with a checkmark
already next to ALTAZ, go to step 9.)
8. Press the ENTER key to activate the ALTAZ mode. The Keypad Hand Controller
will beep and display a checkmark next to the ALTAZ (see Display 19).
9. Press the ENTER key to use the checked mode (ALTAZ). The Keypad Hand
Controller display will look like Display 20.
10. If you have not already leveled the telescope, do so now. When the telescope
is level, select 1 STAR or 2 STAR alignment. The display will look like
11. This message simply reminds you what you should do next. Press ENTER
to show a display like Display 22.
12. Using the monthly star charts in Appendix C, pick an alignment star.
Look at the chart for the current month and face the direction indicated.
The constellations shown are easily found—even in the city. The charts
are approximately 90° wide, with the top of the chart indicating
straight up. If the time is after 9:00 P.M., then use the next month's chart.
Once you identify the constellation, pick any of the labeled stars that
is not within a 10° radius of overhead, but do not choose Polaris,
for reasons made clear below. Polaris is also known as the North Star, and
is shown for reference only.
The TELESCOPE and OBJECT LIBRARY features are accessed through a series
of menus, which are shown on the Keypad Hand Controller Display. You can
scroll up or down through the list of choices by using the PREV and NEXT
keys, and select the indicated menu option with the ENTER key. Menu choices
that are shown in lower case letters are unavailable in the current operating
mode (LAND, ALTAZ, or POLAR). If you try to select a lower case menu option,
the Keypad Hand Controller will emit three warning beeps. Three beeps always
indicate an attempt to perform an invalid telescope operation.
When aligning in ALTAZ, overhead stars can confuse the LX200 because
of an illegal position that prevents the optical tube assembly from slewing
past 90° Altitude to protect the viewfinder from hitting the fork
arm. The LX200 will track an overhead object, but it does so by moving higher
in Altitude up to the illegal position, then the drive speeds up and move
180° in Azimuth so that the optical tube assembly can now be lowered
in Altitude to keep up with the overhead object. Confusion arises because
the LX200 does not know which side of 180° of Azimuth that it is
on. Similarly, Polaris presents position problems in ALTAZ alignment because
it is so close to the North Celestial Pole. In this region of the sky, the
lines of Right Ascension are so close together that even the LX200's high-resolution
encoders can yield ambiguous data.
In our example of January 15, we would use the January chart, face Southeast
and look up about 45°. Orion is probably the easiest constellation
to recognize, and we will use the star Betelgeuse for our example. Use the
PREV and NEXT key to scroll through the list of alignment stars until the
arrow is positioned on Betelgeuse (Display 23).
13. Press the ENTER key to select Betelgeuse. The Keypad Hand Controller
displays a message (Display 24).
14. Center the alignment star (Betelgeuse in our example) in the eyepiece
of the telescope. You can manually move the telescope by loosening the Dec.
Lock Knob and R.A. Lock or electrically by using the N, S, W, and E keys.
If moving the telescope electrically, be sure to use the speed keys, SLEW
to get close, FIND to center in the viewfinder, and CNTR to center the star
in the eyepiece. When the star is centered, press ENTER.
The telescope is now aligned and fully functional, and will automatically
begin to track objects. From this point on, make all telescope movements
by use of the Keypad Hand Controller. Manual movements by loosening the
Dec. or R.A. locks will cause the LX200 to "lose" position, requiring
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c. Using the Telescope
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1) The MODE Key
The LX200 has 5 basic Keypad Hand Controller displays, and the MODE key
is used to move between them. The 5 modes are:
1. Telescope Functions. The TELESCOPE mode is where all telescope functions
are changed or activated and the OBJECT LIBRARY is where the features of
the object library are accessed.
2. Telescope Position. The first display shows the RA and DEC (telescope
position in stellar coordinates) and the second display (accessed by pressing
the ENTER key) shows the telescope position in ALTAZ coordinates.
3. Time and Date. The first display shows local time and Sidereal time and
the second display (accessed by pressing the ENTER key) shows the date.
4. Timer and Freq. This display is a countdown timer and allows the user
to change drive rates. These are advanced features.
5. All Off. This mode simply turns off all displays and backlighting. You
can also adjust the backlighting brightness by pressing the ENTER key and
using the PREV and NEXT keys to adjust the brightness.
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2) Library Object Keys
While in any of the 5 main Keypad displays, you can directly access the
library objects by using the M, STAR, or CNGC keys (see Appendix D of this
manual for a listing of the 64,359 Object Library). Simply press an object
key, and type in the number of the object desired, followed by ENTER. For
example, a good first object for the first part of the year is M42—the
Great Orion Nebula. Press: the M key, the 4 key, the 2 key, and finally
the ENTER key. The display will show data on the object (name, rating, object
type, brightness, and size). Now press GO TO. The telescope will automatically
slew to M42.
If the object entered is not above the horizon, the Keypad Hand Controller
will display the message "OBJECT BELOW HORIZON."
Other good first objects (if above the horizon) are any of the M objects, from
M1 to M 110, and the planets. To find a planet enter:
|OBJECT LIBRARY PLANET LEGEND
If the planet is too close to the Sun for safe viewing (closer than 15°) the Keypad will display a message to that effect.
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3) Daytime Slewing
Some amateurs may want to use the slewing feature of the LX200 to locate
the planets or other astronomical objects during the daytime. If not
done correctly, this can be very dangerous.
The LX200 "knows" where the planets are in relation to the
Sun, but the telescope does not "know" where the Sun actually
is. When the GO TO button is pushed, the telescope will slew to the object
by the most direct route, which may move directly over the Sun. Use extreme
caution before using the GO TO feature of the telescope to locate objects
in the daytime! Looking into the telescope or viewfinder, even for the shortest
fraction of a second, with sunlight entering the optics, will cause instant
and irreversible eye damage. The telescope itself may also suffer serious
damage if it is pointed at or near the Sun.
A responsible adult should supervise every aspect of telescope operation
when children are observing in the daytime.
Use the following procedure to safely locate objects during the daytime,
whether by manual slewing, using the N,E,W,S keys, or using the GO TO key:
1. Before allowing the telescope to move, place the dust covers on the
main telescope and viewfinder (or remove the viewfinder from the telescope
completely). This will keep the Sun's damaging light out of the telescope
should it move across the Sun.
2. Press the GO TO button or manually move the telescope.
3. After the telescope has stopped moving, visually check the telescope's
position to be sure it is not pointing near the Sun. If there is any question
in your mind that the telescope may be pointing at or near the Sun, do not
look through the telescope.
4. Only when you are absolutely convinced that the telescope is pointing
away from the Sun should you remove the telescope's dust cover and observe
5. Above all, be careful and use common sense. Observing the Sun,
even for the shortest fraction of a second, will cause instant and irreversible