Cobra GPS 100 S Operating Instructions Manual page 5

G P S G E N E R A L I N F O R M AT I O N
users. The control segment also ensures that the or a billionth of a second. The atomic clocks within the
GPS satellite orbits and clocks remain as designed. A satellites are so accurate because even an extremely
station can track up to 11 satellites at a time. Each station small time inaccuracy would translate into a extremely
performs this "check-up" twice a day, as the satellites large position difference (1/100 of a second inaccuracy
complete their journeys around the earth. Noted variations, translates to a position difference of 1,860 miles to any
such as those caused by the gravity of the moon and sun and GPS receiver).
the pressure of solar radiation, are passed along to the
External Components
master control station.
The exterior of the GPS satellite has a variety of
The last of the three pieces of the control segment of GPS
antennas. The signals generated by the radio transmitter
are the ground antennas. Ground antennas monitor and track
are sent to your GPS receiver via L-band antennas.
the satellites from horizon to horizon. They also transmit
Another component of the satellite is the radio
correction information to individual satellites.
transmitter, which generates the signal. Each of the 24
satellites transmits its own unique code in the signal.
Space Segment
The space segment includes the satellites and the Delta User Segment
rockets that launch the satellites from Cape Canaveral in
You and your GPS receiver are a part of the user segment
Florida. GPS satellites fly in circular orbits at an altitude of
along with many other private individuals and military
10,900 miles (17,500 km) and with a period of 12 hours.
personnel and their GPS receivers. Military GPS equipment
The orbits are tilted to the earth's equator by 55 degrees to
has been integrated into fighters, bombers, tankers,
ensure coverage of the polar regions. Powered by solar cells,
helicopters, ships, submarines, tanks, jeeps and soldiers'
the satellites continuously orient themselves to point their
equipment. GPS is also used on Space Shuttles.
solar panels toward the sun and their antenna toward the
Cutting-edge Satellite navigation technology coupled with
earth. Each of the 24 satellites, positioned in 6 orbital
your GPS receiver can help overcome many of the hardships
planes, circles the earth twice a day.
and hazards associated with recreation. Your GPS receiver
The satellites are composed of three major subsystems: Solar
allows you to go practically anywhere with confidence
Panels, Internal Components and External Components.
knowing precisely where you are at all times. With your
GPS receiver, you will be able to record accurately any
Solar Panels
location and return to that precise spot time and again,
Each satellite is equipped with solar array panels. These
any time, anywhere.
panels capture energy from the sun, which provides
power for the satellite throughout its life.
Internal Components
Internal components are subsystems such as atomic
clocks and radio transmitters. Each satellite contains four
atomic clocks. These clocks are accurate to a nanosecond
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G P S G E N E R A L I N F O R M AT I O N
Data Field Choices Descriptions
Set Data Display
Your GPS 100 S has the ability to display various types of
information to you. In order to take advantage of the rich
information available to you, it is important that you
understand the meaning of certain terms. Below is a list
of terms that will aid you in using your GPS 100 S.
Accuracy - the distance within which the unit can accurately
locate a position
- average speed throughout the current
Avg Speed
navigation
Bearing - the direction you are currently heading
Set Data Display
Date - the current date
- the destination is the last point on a route, or
Destination
the end of a track
Elevation - your current elevation above sea level
ETA - Estimated Time of Arrival, based on the average speed
you have traveled over the course of your entire route or track
- your current location shown in degrees/minutes
Location
of latitude and longitude
Max Speed - the highest speed that you have traveled
during the current navigation
- total cumulative distance traveled since the last
Odometer
Set Data Display
time the odometer was reset
Power - power icon showing power source (external or
battery), battery charge level, and backlight On or Off
- your current speed
Speed
Time - the current time in your selected time zone
Trip Odom - the distance traveled since the last time the trip
odometer was reset
- the trip time is the total time that has elapsed
Trip Time
during your current navigation since your last reset
Map Page
Gauges Page
Trip Meter Page
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