NorthStar MX500 Operator's & Installation Manual page 261

Glossary
EARTH FLATTENING COEFFICIENT
ECDIS (Electronic Chart Display and Information System)
EDIT
EDIT MODE
ELEVATION ANGLE
ELIPSOID
ENTER
EPHEMERIDES (Singular: EPHEMERIS)
ETA
FATDMA
Version 3.0
See COEFFICIENT OF EARTH FLATTENING.
To modify existing display data via the keyboard.
The state in the navigator where it is possible to enter or change
data. EDIT MODE is accessed by pressing the E-key. Press the E-
key once more to ENTER the data into the memory and leave EDIT
MODE.
The angle made by the line-of-sight range to the satellite and the
horizontal plane of the navigator antenna. Thus, the elevation
angle is 90 degrees when the satellite is overhead and 0 degrees
when it first appears on the horizon. Satellites whose maximum
elevation angle is less than 5 degrees are not good candidates for
providing an accurate position (latitude and longitude) update.
A spheroid whose north-south axis is shorter than the east-west
axis (oblate spheroid).
To store data in the memory of the navigator.
Tabulations of accurate data describing celestial position and
health of the satellites over a 24-hour period. The data is uploaded
to the satellites every 12 hours.
Estimated Time of Arrival. Calculated on basis of the distance to
the destination and the current (or estimated) speed.
Fixed Access Time Division Multiple Access – Data link access
protocol used by base station transponders to allocate transmis-
sion slots on the data link. These slots are fixed and will thus not
change until the base station transponder is re-configured.
Operator's Manual
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