Garmin MX20 Installation Manual page 45

2.9.3.1 EMI/RFI Test
This test validates that interference does not exist between the MX20 and other systems on the aircraft.
Turn off the power to all avionics devices.
2.9.3.2 Test without MX20
1. Start the aircraft engine(s) and switch to engine power, as appropriate.
2. Turn on power to the external GPS navigation source. Clear visibility to satellites is required.
3. Load a flight plan on the external GPS navigation source.
4. Test the function and/or observe for operation of each of the following if installed, or other
appropriate systems.
____ Transponder (if equipped)
____ NAV/VOR/ILS unit and tune to a local frequency (VOR/DME)
____ Any other navigation source
____ Radio Altimeter
____ DME
____ ADF
____ VHF Comm Transceiver
____ Encoding Altimeter
____ Flight Director
____ Marker Beacon Receiver
____ Weather Radar
____ Ground Proximity Warning System
____ Autopilot
____ Directional Gyro/HSI
____ RMI
____ Garmin GTX330 TIS-A Traffic Sensor. TIS-A is available only in areas with a Terminal
Approach Radar.
____ Garmin AT GDL 69/69A Data Link Sensor. Visibility to the southwestern or
southeastern sky is required. The aircraft must be far enough from buildings to avoid
multi-path effects. Note if the GDL 69/69A Data Link Sensor causes interference to
other equipment. The MX20 must be turned on to see any effects on the GDL 69/69A
Data Link Sensor caused by other equipment. The audio portion may be tested without
the MX20 if the optional volume control switches and the GDL 69A are installed. The
GDL 69A powers up with the volume muted. Press one of the volume switches or the
mute switch to adjust the volume.
____ WSI InFlight Weather Sensor. Visibility to the southern sky is required. The aircraft must
be far enough from buildings to avoid multi-path effects. Note if the InFlight sensor
causes interference to other equipment. The MX20 must be turned on to see any effects
on the WSI InFlight sensor caused by other equipment.
____ TAWS Sensor
5. Turn the power off to each of the avionics systems.
MX20 Installation Manual 560-1025-09 Rev E
Installation
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