Magellan GPS ColorTRAK, Руководство пользователя

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Magellan GPS ColorTRAK 3
Getting Started/Initialize
This section shows you how to begin using your GPS ColorTRAK for the
first time. After a brief description of the receiver, it discusses:
• Installing batteries.
• First time use, initializing the receiver.
• Usage.
GPS ColorTRAK Description
The GPS ColorTRAK has a high-resolution color display, a detachable
antenna for exceptional tracking, a backlit keypad and an altimeter. Using
four AA batteries, the GPS ColorTRAK will operate continuously for up to
30 hours and the internal lithium back-up battery will keep the receiver’s
memory active for up to 10 years. The GPS ColorTRAK has a built-in
barometric pressure sensor to give you more accurate altitude readings. The
receiver does not need any calibration or activation, the altimeter function is
automatic. The receiver uses the combination of a pressure sensor and GPS
elevation to give altitude readings of about +/- 200 feet.
Receiver Accuracy
The satellite constellation that provides the GPS information your receiver
uses is maintained by the Department of Defense (DoD). GPS positioning,
for general use, provides 25 meter RMS accuracy or better. Since the signals
generated by these satellites are publicly accessible, the DoD has introduced
errors into the satellite signals for security reasons. These errors are referred
to as Selective Availability (SA).
At present, your GPS position will be accurate within 100 meters horizon-
tally and 150 meters vertically. Due to the errors introduced by SA, it is
possible to get readings outside of these values at times.
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