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
18
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.