190-01007-C1
GTN Xi Part 23 AML STC Maintenance Manual
Rev. 1
Page 7-20
7.3.6 Weather Radar
Perform the appropriate interface check for the weather radar. No additional GTN Xi configuration steps
are required for replacing a weather radar with an equivalent unit.
7.3.6.1 GWX 68/70/75 Weather Radar Interface Check
This section verifies that the interface between the GTN 7XX Xi and the GWX 68/70/75 weather radar is
functional.
1. Power on the GTN Xi in Normal mode.
2. On the home page, touch the
Weather
key and then the
Radar
key.
3. Touch the
Mode
key and select
Standby mode
and wait for the warm-up to complete.
4. Touch the
Mode
key again and select
Test mode
.
5. Verify that the GWX 68/70/75 begins sweeping and the test pattern is shown.
6. If supported by the installation, verify that stabilization is on (“STAB On” is displayed in the
upper-right corner of the radar display).
7. Touch the
Mode
key, set the mode to
Off
.
8. Repeat steps 1 through 7 for the second GTN 7XX Xi, if installed.
7.3.6.2 ARINC 708 Weather Radar Interface Check
This section verifies that the interface between the GTN 7XX Xi and ARINC 708 weather radar is
functional.
WARNING
Aircraft should be outdoors and personnel should not be in front of the weather radar
when it is radiating (i.e., when Weather or Ground mode is selected on the GTN Xi).
1. Power on the GTN Xi in Normal mode. If there are dual GTN 7XX Xi units, power on both in
Normal mode.
2. On each GTN Xi, touch
Weather
from the home page and then
Radar
.
3. On GTN Xi #1, touch the
Mode
key and select
Standby Mode
and wait for the warm-up to
complete.
4. Touch the
Mode
key again and select
Test Mode
.
5. Verify that the radar begins sweeping and the test pattern is shown.
6. If stabilization is supplied to the radar, turn the radar to Weather mode and turn stabilization on in
the weather menu. Verify that “STAB On” is displayed in the upper-right corner or the radar
display. If “STAB INOP” is displayed, verify that stabilization is being supplied to the weather
radar R/T.
7. Touch the
Mode
key to set the mode to
Off
.
NOTE
If only one GTN 7XX Xi is installed, the following steps do not have to be carried out.
8. Repeat steps 1 through 7 for GTN Xi #2.
