The GTO control box contains all of the circuitry to drive the two servo motors and the logic required to circumnavigate the sky. This electronics box is mounted directly on the polar axis of the 1200 and 900 mounts and is a stand-alone unit for the 400 and 600E mount. We provide a pouch with a handle for the freestanding unit.

The main function of the servo controller is to drive the RA and DEC motors, which are DC servos with built-in shaft encoders. The rotation rate of the motors is controlled with a servo feedback loop. The servo looks at the return pulses from the shaft encoders and adjusts the current to the motor so that the rate is identical to the commanded rate (i.e. from .25x sidereal to 1200x sidereal). The servo is digitally controlled, and the shaft position is updated at a rate of 2000 times per second.

• Machined aluminum housing provides robust protection for electronics.
• Dovetail construction allows quick removal from 900 and 1200 mounts.
• Removeable microprocessor chip allows upgrades in future.
• 12V connector for locking power cable.
• Connector for SBIG ST-4, ST-6, ST-7, ST-8 and ST-10 Star Tracker/Imaging Systems or any CCD with modular RJ-11-6 connector.
• Two 9-pin RS-232 serial ports (DB9 female connectors) so that user can use DigitalSky Voice and a planetarium program (i.e. Software Bisque's TheSky™ software) simultaneously, if desired. The user must have two COM ports available on their personal computer to use the software together.
• Focus connector - for 3.5mm phono plug (JMI or Meade electric focusing motors).
• Reticle connector - for guiding eyepiece with an illuminated reticle that has a 3.5mm phono plug or the cable for our own PASILL3 or PASILL4 (Polar Alignment Scope).
• 6 volt output accepts 3.5mm phono plugs to power Pentax 6x7 camera directly from the mount.
• Northern and Southern Hemisphere switch.
• GTO Keypad Controller locking connector.

The keypad is the communication center for the operation of your GTO mount. We have designed this unit to be as intuitive and easy to use as possible, while filling it with terrific features to make your observing session productive and pleasurable.

The keypad allows you to control all the essential telescope functions such as selection of tracking and guiding/centering or slewing rates, PEM (permanent error memory), declination backlash control, RA/Dec reversal, polar alignment, brightness of the crosshair of your illuminated guiding eyepiece and movement of N-S-E-W directional keys.

Most buttons are assigned to one function only. You do not have to remember shift key patterns or complex keystroke sequences. The directional buttons are shaped like arrows to help you find them in the dark without looking at your keypad. The stop button is readily accessible if you need to cancel any slewing request immediately.

The menu system is very easy to navigate. Each 4-line screen will display several choices which correspond to a number button. Simply press the number button to initiate the command, e.g. "1=M, 2=NGC." When you press "1" the Messier entry screen will display and you can enter the number of the object that you wish to see. Press GOTO, which will cause the mount to slew. The <PREV and NEXT> buttons will allow you to scroll quickly through the lists of common names or from one menu to another.

The advanced keypad features allow you to slew automatically to objects in the Messier, NGC, IC, ADS double star and Abell galaxy cluster databases; bright stars; all planets; the Moon; Sun; as well as any RA/Dec coordinate. The search function locates objects based on type and magnitude. The tour function guides you on a tour of interesting objects by constellation. The What's Up feature will suggest interesting objects that are up during your observing session. All of these features provide you with lots of observing ideas.

You will be very pleased with the intuitive operation of this controller. There are no complicated sequences of keystrokes to remember. It is so easy to use that even if you don't use it for a few months, you will feel at home with the keypad very quickly.

• Handheld keypad controller with red backlit alphanumeric keypad and red 4-line by 20-character data display.
• Vacumn-fluorescent display rated to -40 degrees F or C (F and C are are equivalent at this temperature) allows hardy observers to view or image on cold winter nights. Normal computers or PDA units cannot be used at these temperatures.
• Directional N-S-E-W keys provide immediate response when you wish to center an object or cruise the surface of the moon.
• R.A. and declination reversal for correct object orientation and movement in eyepiece.
• PEM - Permanent Error Memory correction. Make your correction just once, remains in memory permanently.
• R.A. and declination backlash control.
• Stores 9 observing site locations.
• Specify safety zone so that tripod does not interfere with telescope during slewing operation.
• Quick and easy polar alignment routines, even during daylight!
• Adjust brightness of the reticle output for your illuminated guiding eyepiece or polar alignment scope.
• Automatic meridian swapping in go-to slewing mode.
• Continues to track at sidereal rate, even while slewing so that your position is always accurate.
• More than 17,000 objects in extensive databases: Messier (110), NGC (7840), IC (5,386), ADS double stars (215), Abell galaxy clusters (2,712), calibration stars by common name (200), Greek star names by constellation (1053), common objects (100), planets (8) , Moon and Sun.
• Enter catalog or common star number, solar system object, RA/Dec coordinates or common name of object; press GO TO and your telescope will automatically slew to the object.
• Search and tour functions assist you to plan observing session.
• Display will indicate if object is below horizon and cancel slewing request.
• STOP button to cancel your slewing request when the telescope is already moving.
• Display information about objects (object type and magnitude) before slewing.
• Timer will let you know when the exposure time of your astrophoto is complete.
• Continuous readout of current position.
• Park in any position you choose or select one of three preprogrammed park positions.
• Meridian swap delay function allows astrophographers to take a series of images for a mosaic near the meridian without the mount swapping sides.
• SmartGuide control provides variable speed capability to both axes.
• Altitude/Azimuth display allows you to position the mount for fixed targets to any Alt/Az point. This is great for taking dark frames.
• What's Up Now function will suggest objects to view based on what is actually above the horizon at the time.
• External Auto Connect allows you to sync the keypad, mount and computer for seamless control of your mount.
• Reference Park allows you to start the mount in the field by placing the telescope in Park1 position for quick daytime polar alignment.
• Retractable hanger.
• Future firmware upgrades available through internet downloads.

Keypad