Garmin GPS 400 Pilot's Manual And Reference page 135

CDI Scale / Alarms— allows you to define the scale for the GPS 400's on-screen
course deviation indicator. The scale values represent full scale deflection for the
CDI to either side. The default setting is "Auto", which starts the CDI scale at 5
nm (en route), and gradually ramps the scale down through 1 nm (terminal area)
to 0.3 nm during an approach. For auto CDI scaling adjustments to occur, you
must have an active direct-to or flight plan with an airport or approach as your
final destination, or be within 30 nm of a departure airport. Note that the
Receiver Autonomous Integrity Monitoring (RAIM) protection limits listed below
follow the selected CDI scale, changing automatically with the "Auto" setting:
CDI Scale
+/-5.0 nm or Auto (en route)
+/-1.0 nm or Auto (terminal)
+/-0.3 nm or Auto (approach)
An arrival alarm, provided on the CDI scale / alarms page, may be set to notify
you with a message when you have reached a user-defined distance to the final
destination (the direct-to waypoint or the last waypoint in a flight plan). Once
you have reached the set distance (up to 99.9 units), an "Arrival at [waypoint]"
message will be displayed.
Units / Mag Var— allows you to configure the displayed data to standard or met-
ric units of measure. This setting applies to distance, speed, altitude, fuel, pres-
sure and temperature. Also provides three magnetic variation (heading) options:
True, Auto or User-defined. If "Auto" is selected, all track, course and heading
information will be corrected to the magnetic variation computed by the GPS
receiver. The "True" setting will reference all information to true north, and the
"User" setting will correct information to an user-entered value.
RAIM Protection
2.0 nm
1.0 nm
0.3 nm
AUX PAGES
Setup 1
CDI scales and corresponding modes:
Enroute
Terminal
Approach
7