PRIMUS
r
1000 Integrated Avionics System
A28--1146--112--00
B--7
PRIMUS
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660 Weather Radar System
D
FP (Flight Plan)
-- In the FP position, the WX transmitter is placed
in standby and the PFD or MFD map range has been selected up
to 1000 NM. There is no radar data displayed in this mode.
NOTE:
When weather is not selected for display, the MFD has its
own range control. The PFD does not require range
control.
D
TEST
-- The TEST position selects the radar test mode. A special
test pattern is displayed to verify system operation. The green TEST
legend is displayed in the MFD mode field.
WARNING
IF THE AIRCRAFT IS ON THE GROUND AND FORCED STANDBY
(FSBY) IS OVERRIDDEN, THE TRANSMITTER IS ON AND
RADIATING X--BAND MICROWAVE ENERGY IN THE TEST MODE.
REFER TO MAXIMUM PERMISSIBLE EXPOSURE LEVEL (MPEL)
IN THIS APPENDIX.
9
GAIN KNOB
The GAIN knob is a rotary control and a push/pull switch that controls
the receiver gain. When the GAIN switch is pushed, the system enters
the preset, calibrated gain mode. Calibrated gain is the normal mode
and is used for weather avoidance. In calibrated gain, the rotary
function of the GAIN control is disabled.
When the GAIN switch is pulled, the system enters the variable gain
mode. Variable gain is used for additional weather analysis and for
ground mapping. In the WX mode, variable gain can increase receiver
sensitivity over the calibrated level to show very weak targets, or it can
be reduced below the calibrated level to eliminate weak returns.
WARNING
HAZARDOUS TARGETS ARE ELIMINATED FROM THE DISPLAY
WITH LOW SETTINGS OF VARIABLE GAIN.
In the GMAP mode, variable gain is used to reduce the level of strong
returns from ground targets.
Minimum gain is set with the control at its fully ccw position. Gain
increases as the control is rotated in a cw direction from full ccw to the
12 o’clock position. At the 12 o’clock position, both the gain and the
sensitivity time control (STC) are at their maximum values. Additional
cw rotation removes STC. At the full cw position, the gain is at maximum
and the STC is at minimum.
