Furuno 1942 MARK-2 - Manual (Page 11)

1-2
A
B
C
D
Own ship
(radar)
D A
B
C
Heading marker
Targets
Own ship
in center
(A) Bird's eye view of situation (B) Radar picture of (A)
Range and bearing
of a target, relative
to own ship, are
readable on the PPI.
Figure 1-1 How radar works