d. The color of the fourth target band
(65 to 75 nm) is red
e. The two red target bands flash on
and off approximately once each
5. Momentarily press WX/C push button
and slide TGT ALRT control to ON.
Verify that the letter T in a red box
appears in the target alert field.
6. Press TEST push button and observe
that when the test pattern display
crosses the centerline, the T is
replaced by a flashing TGT label.
Slide TGT ALRT control to OFF to
disable the function.
7. Verify that 100 (nm) is displayed in the
upper right-hand corner and that the
first four range marks are labeled with
the correct numerics.
8. Slide AZ MK control to ON and verify
that azimuth marks displayed in cyan
at 30° intervals. Slide AZ MK control
to OFF to remove azimuth marks.
9. Momentarily press WX/C push button
to erase display, then press TEST
push button. After approximately
2 seconds, momentarily press FRZ
and verify that the 1 2 3 display
beneath the color bar is replaced by
flashing FRZ label. Verify that only a
portion of the test pattern is displayed
and there is no further updating.
Momentarily press FRZ push button
and verify that the display begins
updating starting at the current scan
10. Press 10 (nm) range push button and
momentarily blanked and the restored
to the previous display.
11. Momentarily press WX/C push button
and verity that WX appears in the
Mode field and 10 appears as the
selected range. Verify correct range
12. Press each range push button in
succession (25 / 50 / 100 / 200 / 300)
and verify that range numerics change
appropriately with each selection.
13. Momentarily press WX/C push button
and verify that CYC is displayed in the
GAIN control just out of
PRESET and verify that 1 2 3 remains
in the auxiliary field.
15. Momentarily press WX/C push button
and verify that WX is displayed in the
mode field and that VAR replaces 1 2
3 in auxiliary field.
16. Momentarily press MAP push button
and verify that MAP is displayed in the
Mode field. Verify that the color of the
range marks and alphanumerics is
17. Momentarily press STBY push button
to return radar to non-transmitting
GAIN control to
(4) Fault Displays. Display colors are
continuously monitored by the color bar and 1 2 3
legend in the auxiliary field. If a fault causes a change
to unfamiliar colors, the severity level denoted by the
faulty color(s) is directly coded by the 1 2 3 legend.
Other circuits continuously monitor performance
and loading of system power supplies. A fault
resulting in power supply operation outside of preset
limits will cause the system to shut down and the
display will be blank. Should this occur, use the
following procedure to recycle the system:
1. Rotate INT / OFF control to OFF.
2. Verify that aircraft radar circuit breaker
3. After a few seconds, rotate INT / OFF
control to mid-point and press TEST
If the fault was of transient nature, the system
may operate satisfactorily.
(5) Ground Mapping. Ground mapping
operation is selected by pressing the MAP push
button. Turn the TILT control down until the desired
amount of terrain is displayed. The degree of downtilt
will depend upon the type of terrain, aircraft altitude,
and selected range.
For the low ranges (10, 25, and 50 nm), the
transmitter pulse width is narrowed and the receiver