NorthStar 961x Manual Do Utilizador
Glossary
Page G-6
961 Operations and Reference Manual Rev. D
secondaries
The "slave" loran transmitters in a chain of at least three sta-
tions.
tions.
sentence
A group of data in one of several formats defined by the
National Marine Electronics Association.
National Marine Electronics Association.
SOG
S
peed Over Ground. The actual speed of your vessel relative to
the bottom of the water; that is, the speed your vessel is actu-
ally going.
ally going.
SNR
S
ignal-to-Noise Ratio. A guide number for determining the rel-
ative quality of GPS, DGPS, or loran signals as compared to
background radio noise.
background radio noise.
TDs
T
ime Differences. The measured amount of time—in millionths
of a second—between those loran signals received from the
master and those from the secondary station. These measure-
ments are used to determine position, according to the
Loran-C system.
master and those from the secondary station. These measure-
ments are used to determine position, according to the
Loran-C system.
tide
The vertical rise and fall of water caused by the gravitational
pull of the moon and sun.
pull of the moon and sun.
track
A sequence of position measurements, or a desired line of
travel, defined one second at a time; that is, defined by actu-
ally travelling from point A to point B. Your track is a continu-
ous record of everywhere your vessel has been.
travel, defined one second at a time; that is, defined by actu-
ally travelling from point A to point B. Your track is a continu-
ous record of everywhere your vessel has been.
trip
A sequence of waypoints, including past, active, and future
ones.
ones.
waypoint
A particular location, defined by its lat/lon, distance and bear-
ing, or Loran-C TDs, which is used as an intermediate or final
destination.
ing, or Loran-C TDs, which is used as an intermediate or final
destination.
XTE
See cross-track error.