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FAQs

Q: Why are there no satellites in the Available satellites list box?
A: Either you have wrongly specified the location of the satellite orbital element files, or there are no files matching the extensions "tle" or "2li" that contain two-line data in that folder.

Q: Why doesn't a satellite image load?
A: The images must be named according to the WXsat convention - MMDDhhmm.bmp or whatever.  For example, without a pass selected, the program might start up with the date 26th February 1999 at 1327 in the "When" box on the "Ground Path" tab.  It would therefore look for files named 02261327.jpg.  When using the "Timeframe from File" option on the World Map page, loading a file merely sets the date and time for the satellite display.  More information on file names and locations.

Q: Can the program display using my local time zone?
A: No, the program only displays UTC.  Please ensure that your Windows, Control Panel settings are correct to reflect your actual time zone, and state of daylight saving time.  If you wish to use, for example, WXSat to record wave files, and wish to have those named with correct UTC times, please see here.

Q: Why do I have no background to the World Map?
A: You may have used an older version of an unzip utility that could not handle the long file names for the image maps.  Ensure that the file SmallUserMap.jpg is present and correctly named in the same folder as WXtrack.exe.  You can also use the names UserMap.bmp, UserMap.jpg and LargeUserMap.jpg.  Download these from the Web site.  There was an error in version 2.6.2 that prevented new users from getting a background map.

Q: Why are no satellites displayed on the World Map?
A: You haven't selected any from the available satellite list.  More information on the Setup Tab.

Q: Why are there lines across the display in Azimuthal Equidistant projection.
A: With some display drivers, you may need to turn down the graphics acceleration to avoid lines being drawn where a footprint or grid line crosses from top to bottom or left to right on the display.  This appears to be rather graphics board and driver dependant, and you might wish to check that your display drivers are up-to-date.  Graphics acceleration is found by right-clicking My Computer, and selecting the performance tab.

Q: I downloaded the 11MB data file but the World Map looks no different.
A: The ETOPO5 file is only used for ground path prediction where the higher resolution helps, not for the world map background.

Q: I downloaded the 11MB data file, but my ground path predictions are no different.
A: You forgot to rename the expanded data file to etopo5.elev.

Q: Why does the elevation drop quite suddenly by about half a degree at the end of a pass?
A: The program allows for atmospheric refraction, which makes the satellite appear higher than it actually is.  Once the apparent elevation of the satellite goes below zero, it is not appropriate to apply the refraction term.  Thus you will not see apparent elevations in the range 0 to -0.5 degrees.

Q: How do I use multiple locations?
A: On the Setup tab, you can select from multiple locations using the Choose location drop-down list.  The Edit locations button gives access to a small dialog box that enables you to alter the height and other details for a location, or to add a new location.  Note that the location name cannot contain a space.  You can also use different horizon profiles for each location by adding the location name as a prefix, e.g. EdinburghHorizon.dat.

Q: Why does the AOS for a satellite say n/a?
A: Either there are no more passes today, or you added a satellite but didn't force regeneration of the pass list.  Press the "Make pass list" button.  You may also have run off the end of the pass list if you are near midnight UTC.

Q: Why don't the ISS options work?
A: You need to select the ZARYA module of the ISS which is catalogue number 25544 for the ISS to be correctly detected.  This is the module normally used, so no special action should be required.  You may also need to ensure that the line style you have selected for Radio Horizons is visible!

Q: I clicked the World Map tab from the Setup tab, but my selected satellite pass isn't set as the manual time.
A: You should click the Map from pass button, simply clicking on the World Map tab isn't enough.

Q: I clicked the Ground Path tab from the Setup tab, but my selected satellite pass isn't detailed.
A: You should click the Picture from pass button, simply clicking on the Ground Path tab isn't enough.

Q: I clicked the Ground Path tab from the World Map tab, but my selected satellite pass isn't detailed.
A: You should click the Make Picture button, simply clicking on the Ground Path tab isn't enough.

Q: How do I see local time on the map?
A: If information is available from Windows, the hint of the date and time boxes at the bottom of the Map tab will show the local time.  Hold the mouse over the date or time control, and the last date and time will be shown briefly.

Q: I'm running Windows 98, and unchecking the Daylight Saving option seems to make no difference.
A: Download and try the Time Zone Editor from the Microsoft Windows Kernel Toys.

Q: Why do the overlay grid lines appear bent, rather than smooth curves?
A: This is not an error.  The overlay mimics the interpolation process in the NOAA satellites which converts the high-resolution sensor data down to the APT transmission standard.  This interpolation process fits a number of line segments to a curve, and where two line segments meet, there is a sudden slope change.  Applying the process to latitude and longitude lines produces the discontinuities you observe.  The artifacts produced by applying the process to the irregular country boundaries are much more difficult to see.

Q: What is the wavy line covering the majority of the map?
A: The terminator between day and night.  This will vary in shape between spring, summer, autumn and winter, being more sinusoidal in summer and winter, but more square-wave in spring and autumn when the sunrise and sunset occur at similar times in all latitudes.  Turn on the Options, Show night time shading for a more realistic display of day/night illumination.

Q: Why do I get no overlay files?
A: Perhaps you don't have the Options, Save pass details and Options, Show overlay settings checked?

Q: Why can I not get the satellite frequencies?
A: The file TLEnotes.txt must be in the same folder as the other Kepler data.

Q: What is the large yellow blob?
A: The sun