positions and the GPS time before you can perform the actual position calculation and before the GPS becomes functional. After the first position fix has been established, it still takes additional 10 minutes before all relevant data has been received from the satellites. The position estimate accuracy improves during this time as more satellites can be used for position calculation.
The downloaded data is valid roughly for the next four hours during which the re- ceiver starts more quickly, typically in less than 10 seconds if it was turned off in between.
You should turn off the GPS when you do not need it. This is because satellite tracking consumes large amounts of power. Suunto M9 uses the lowest power consuming GPS technology available but you should still turn off the GPS when you do not need it.
2.4.5. Versatility
The GPS system is run by the United States Department of Defense and has been fully operational since 1995. At least 24 operational satellites circle the globe every 12 hours in 6 orbital planes with 4 satellites per plane to provide a true global coverage. A worldwide ground control network monitors the health and status of the satellites. The system works 24 hours a day regardless of the weather. It can provide service to an unlimited number of users and it is free of charge.
NOTE: The very first time you initiate the GPS, it will take longer than usual for the GPS to start, as it has no reference to its current location. This may also happen if the GPS has not been used for a long time.
Please activate your new Suunto M9 GPS at least once before sailing out. Subsequent GPS starts will take less time. To minimize the GPS initiation time, hold the unit steady in one position with the display facing up and make sure you are located in an open area so that the unit has a clear view to the sky. After starting the GPS (i.e. after it has a fix), the unit can be moved more freely without losing the connection to the satellites. The signal strength bar on the unit’s display indicates the fix. (See section 2.1.4, GPS Activity and Accuracy Bar Display)
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