Garmin GNC 300 Pilot's Manual page 106

APPENDIX C
UNIT SETTINGS
SECTION
7
Maintenance
CDI Settings
Magnetic Variation
When the 'Auto' CDI setting is selected, the
GNC 300 will automatically change the CDI
scale when you are within 30 nm of a departure
or arrival airport. During approach operations,
the 'Auto' setting will be automatically selected to
provide a smooth CDI transition from the 5.0 nm
to the 0.3 nm scale.
Entering a user magnetic variation.
96
The first available page under the settings submenu is the CDI settings page,
which allows you to define the scale of the GNC 300' s course deviation indicator.
To change the CDI scale:
M
1. Press and hold , and rotate
C
2. Press twice and rotate
O
3. Rotate to highlight 'ok?' and press
Note: the selected CDI scale will not take effect until approved.
The scale values represent full scale deflection of the CDI to either side. The
+
default setting is 5.0 nm. The 'Auto' setting will start the CDI scale at 5 nm, and
-
gradually ramp down the scale to the 1 nm range once you are within 30 nm of a
departure or arrival airport. You must have an active direct-to or route with an airport
as your final destination waypoint, or be within 30 nm of a departure airport. If you
have an active approach, the scale will gradually ramp down to the 0.3 nm range
once you are within 2 nm of the final approach fix.
Note that the GNC 300 uses Receiver Autonomous Integrity Monitoring
(RAIM) to cross-check its position. The 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)
The GNC 300 has three magnetic variation options: true, auto, or user-defined.
To set the magnetic variation:
M
1. Press and hold and use
C
2. Press twice and use
O
3. If user is selected, use
to enter the value and E or W. Press
O
to select the CDI settings page.
K to select 'Auto', ' + - 5.0 nm', ' + - 1.0 nm' or ' + - 0.3 nm'.
E
to approve.
RAIM Protection
2.0 nm
1.0 nm
0.3 nm
O
to display the 'Mag Var/Arvl Alarm' page.
K
to select auto, true or user.
to highlight the magnetic variation value, and use
C
to finish.
K O
and