P R O C E D U R E
T R O U B L E S H O O T I N G
(g) Range switches - As required.
Satisfactory operation of the
weather radar shall be verified
using all sweep ranges.
(h) TILT control - Move up or down
to observe targets above or below
aircraft. Verify that echo displays
change in shape and location
only and that weather targets do
not not change shape or location.
Ground targets will not change
shape or location. Ground targets
are selected as a function of tilt.
(i) Antenna stabilization check:
(1) Fly to an altitude above
10,000 feet AGL.
(2) GND MAP pushbutton selec-
tor switch - Depress to select
(3) Range switches - Select 20
(4) GAIN control - Maximum.
(5) TILT control - Pull out to dis-
able stabilization. STAR OFF
should appear in upper left
comer of display.
(6) While flying level (0 pitch,
0° roll), adjust TILT control
to obtain a video pattern
throughout the upper range
marks. Note TILT control set-
ting. If the inner ring of video
is not parallel to the range
mark, the error is caused by
mechanical displacement of
the antenna about the roll axis
of the aircraft. Use TILT con-