NorthStar 958 Operator's Manual page 216

Northstar 958 automatically calculates magnetic variation and
uses it to display bearings as magnetic north. The variation at
any location changes slowly over a period of years, and the
unit compensates, according to the current calendar year.
master
The primary loran transmitter in a "chain" of at least three
stations which initiates a series of coded pulses and is followed
by the secondaries.
mile (statute)
A unit of measurement (distance) equal to 5,280 feet (1,609.3
meters).
nautical mile (nm)
An international unit equal to 6,076.115 feet (1,852 meters)
used officially in the U.S. since 1959. A nautical mile is about
800 feet more than a statute mile.
nav aid
Aids to navigation often used on coastal and inland waters.
Buoys, lighthouses, and daymarkers are nav aids.
NMEA
National Marine Electronics Association. The industry group
that establishes the standards for exchanging data between
electronic navigation equipment. The standard that's currently
in wide use is NMEA 0183, which specifies the format for
sentences containing specific types of data.
Phantom Loran
Northstar's exclusive loran-simulation feature that
mathematically converts GPS lat/lon coordinates to loran
TDs—in real time, as you travel—enabling you to display your
current position as TDs.
PPNM
Pulses Per Nautical Mile.
radar
Radio Detecting And Ranging.
rhumb line
A constant, true direction to your destination, which appears
as a straight line on a Mercator grid. Compare with great
circle.
route
A group of two or more pre-defined waypoints that form a
connected path to and/or from specific locations. In its
simplest form, a route can be a straight line to a single
waypoint.
satellite
An object orbiting the earth. GPS satellites are controlled by
ground stations, and transmit signals that can be used to
calculate position and speed. WAAS satellites.
Page 208 958 Operator's Manual, Rev. A