PRIMUS
r
880
Digital
W
eather
Radar
System
A28-1146-102-00 RadarFacts
5-69
GROUND MAPPINGGround mapping operation is selected with the GMAP button An
example of ground map display isshown in figure 5-49. Turn the TILT
control down until the desired amount of terrain is displayed. The
degreeof down-tilt willdepend upon the typeof terrain,aircraft altitude,
andselected range. Tables 5-13 and 5-5show tiltsettings for maximal
ground target display at selected ranges.
Ground Mapping Display
Figure 5-49
Forthelowranges(5,10,25,and50 NM), the transmitterpulsewidthis
narrowed and the receiverbandwidthiswidened to enhancethe
identificationofsmall targets.In addition,the receiverSTCcharacteristics
are alteredto betterequalizeground targetreflectionsversusrange.As
aresult,the presetgainposition isgenerallyused to displaythedesired
map.The pilotcan manuallydecreasethe gaintoeliminate unwanted
clutter.