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select your telescope from a different (much larger) list of possibilities. Once you have used the Telescope dialog to tell Guide what sort of telescope you have and which serial port it uses, a "Scope Pad" item will be added to the main menu. Clicking on "Scope Pad" toggles display of a little floating dialog box, loosely modelled on the LX-200 control pad. The next step is alignment. For this purpose, systems fall into two categories: the JMI/MG-III encoder-based systems, and everything else. "JMI/MG-III" is used as a shorthand to refer to a huge range of devices: the JMI NGC-Max series, the MicroGuider III, Ouranos, Lumicon, Advanced AstroMaster, Orion Sky Wizard, B-Box, and a few others. Despite the variety of labels, all of these are actually made by Tangent Instruments, and are also referred to as "Tangent Instrument boxes." JMI/MG-III type systems are also called "dumb boxes", because all they return to the PC is the position of the encoders. The PC is expected to provide the "brains" needed to convert encoder readouts to RA/dec data. All the other devices, such as the LX-200 and Ultima 2000, have built-in alignment systems. Once you have aligned them (typically by pointing them at one or more known reference stars), Guide is ready to communicate with them. But for JMI/MG-III type systems, the alignment has to be done using Guide. The process is described in the next chapter. As with the LX-200 control pad, the Scope Pad provides four buttons to allow motion north, south, east, and west, plus a central "stop moving" button; and there are four rates of motion provided. (Obviously, none of these work with encoder-based systems. Such systems don't have motors with which to move the telescope.) There are some additional buttons below these that are specific to computer control of a scope. "Slew Scope" is used for aiming the telescope. If you have found and clicked on a location in Guide, hitting "Slew Scope" will slew the telescope to that location. You can also do this by hitting F11 or Ctrl-F1 at any point in Guide. For the JMI/MG-III based systems, there are again no motors to move the telescope. In this case, a red indicator appears on the chart to show where the telescope is pointed, and is updated every second or so. Clicking on "Slew Scope" again will shut off the display of this indicator. The "Slew Guide" option will cause Guide to find out where the telescope is pointed. Guide will then pan to that location, leaving
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