Leisure Time LX20 - Manual (Page 18)

side of the keypad. Altazimuth coordinate readings can
still be displayed in the coordinates mode (see MODE 2,
page 22). Refer to QUICK START (page 9) for the LAND
menu option, for full operating procedures. You will
also find that the addition of the Meade #928 45-Degree
Erect Image Prism or the Meade #924 Porro Prism
instead of the standard supplied star diagonal prism, will
give the normal right-side-up and left-to-right views that
you are accustomed to when using a spotting scope.
3. SMART: The SMART menu file controls the Smart Drive and
allows you to train almost all of the periodic error from the
Right Ascension drive worm gear (errors induced by tiny gear
imperfections that tend to slightly speed up or slow down the
drive tracking speed, that occur in a regular 8 minute pattern,
or for every rotation of the worm) for greatly enhancing the
tracking characteristics or the amount of East and West drift
of your LX200. This greatly simplifies guiding during
astrophotography. The menu also has provisions for
correcting Declination drift. Smart Drive will retain the
training given to the R/A drive, even after the telescope is
turned off. There is of course a way to erase any training
given to it at your command.
The SMART menu has five options. They are; LEARN,
UPDATE, ERASE, DEC LEARN, and DEC CORRECT. To
use the Smart Drive, the LX200 must be mounted with the
optional equatorial wedge (see APPENDIX A, page 25),
equipped with an illuminated reticle eyepiece*, and used in
the POLAR align menu selection. Be sure to train the Smart
Drive in the 60.1 Hz Quartz setting that the LX200 will be
automatically set at power up. Thereafter, you can adjust this
setting in the TIMER/ FREQ mode and still enjoy the periodic
error correction.
Once a polar alignment has been completed, your LX200 will
point to a bright star overhead that will be near the Celestial
Equator. This will be a good star to train the Smart Drive on.
You can of course, move to another star just as long as you
are near 0 degrees in declination and more or less overhead
in Right Ascension. Now is good time to set the brightness
and/ or the pulse rate (see THE LX200 KEYPAD HAND
CONTROLLER, page 14) of the illuminated reticle on the guide
star and practice guiding for a few minutes.
To actually begin training the Smart Drive, move the LCD
arrow to LEARN by using the PREV or NEXT key and press
ENTER. There will be numbers that will appear next to the
LEARN display, that will begin counting down to zero. The
highest number that can appear is 240. The period of the
worm is eight minutes and the number represents a sector of
the worm wheel which will change to the next lower digit
every two seconds. As the keypad display approaches sector
5, an alarm will alert you that training is about to commence.
At this point try to keep the star on the same location of the
crosshair during the eight minute training sequence by
pressing the N, S, E, and W keys. After eight minutes, the
training is over and Smart Drive will play back the drive
corrections automatically, dramatically improving the R.A.
drive tracking.
If you wish to further refine the accuracy, move the LCD
arrow to UPDATE and press ENTER and follow the same
instructions as above. This can be done in UPDATE as many
times as you wish. With each training the Smart Drive will
average your training sequences.
If you find that you have made a mistake in training (e.g.
pushed E instead of W when you should have), you can
eliminate the memory by moving the LCD arrow to ERASE
and press ENTER.
A star that drifts consistently North or South during guiding,
can also be corrected for. Move the LCD arrow to DEC
LEARN and press ENTER. Begin making drive
corrections immediately by pressing any of the direction (N,
S, E, W) keys to keep the star on the crosshair of the guiding
eyepiece. It is suggested that you train in DEC LEARN for at
least half of your intended exposure time for an astrophoto.
The longer that you train, the more accurate the DEC
LEARN will be. Once the desired time is finished, press
ENTER and the training will cease. The Smart Drive will then
determine how many key pushes that you gave in N and S
and choose the direction based from which direction received
more commands. It then averages the time between key
pushes in the chosen direction. In this way, the Smart Drive
can correct for Declination drift (should your polar alignment
be slightly off), or will allow you to more precisely guide on
non-stellar objects, such as comets, asteroids, etc.
To play back your DEC LEARN training, move the LCD arrow to
DEC CORRECT and press ENTER. To halt the play back press
ENTER again. To erase the DEC LEARN • training, either move
the LCD arrow back to DEC LEARN and press ENTER twice or
turn the LX200 off.
4. 12/24 HR: The 12/24 HR menu selection of the TELESCOPE
file simply toggles between a 12 and 24 hour display of
local time in the time mode.
To toggle between 12 and 24 hours displays, move the
arrow to 12/24HR and press ENTER. To return to the
original setting, press ENTER again.
5. HELP: The HELP menu selection of the TELESCOPE file is
an electronic mini-manual that will briefly describe the
function of each command key on the LX200 keypad.
To use this menu, move the arrow with the PREV or NEXT
key to HELP and press ENTER. To read the lines of text, use
the PREV and NEXT keys. To exit, press MODE.
6. REVERSE N/S: The REVERSE N/S menu selection of the
TELESCOPE file reverses the direction of the telescope in
North and South movements (e.g., when you press the N
key the scope will move South or down instead of North or
up). This is especially useful during some guiding
applications in imaging and observing.
To use the REVERSE N/S menu, move the arrow to
REVERSE N/S and press ENTER. If you wish to return the
direction commands to the original setting, press ENTER
again.
7. REVERSE E/W: The REVERSE E/W menu selection of the
TELESCOPE file reverses the direction of the telescope in
East and West movements (e.g., when you press the W key,
the telescope will move East instead of West).
To use the REVERSE E/W menu, move the arrow to
REVERSE E/W and press ENTER. If you wish to return the
direction commands to the original setting, press ENTER
again.
8. BALANCE: When adding optional equipment to the LX200,
like a heavy camera, it is often necessary to rebalance the
telescope using the Meade #1404 Tube Balance Weight
Systems.
Selecting option #8 from the TELESCOPE menu moves the
LX200 telescope rapidly up and down in Declination. This
provides an easy way to determine when the telescope is
balanced in the Declination axis. (Remember, loosening
the Dec. lock to check the balance will cause the LX200 to
lose alignment.)
When the telescope is out of balance, the LX200 will draw
more current when slewing in the "heavy" direction and the
Dec. motor will sound different.
After selecting option #8, watch the Ammeter and listen to
the Declination motor to determine when the LX200 is
balanced.
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