Instruction Manual

RA51/52/53/54/55 INSTRUCTION MANUAL – 05 7

True Motion (TM)

In this mode, the boat icon is displayed as if it is moving on a marine chart while targets such as

islands and seashores are fixed in position. When the icon reaches a certain position on the screen

(approx. 2/3 of screen size), it is placed back on the opposite side on the screen. North is at the top

of the screen. External heading and speed data are needed for this mode.

VRM (Variable Range Marker)

This adjustable circular-shaped marker can be used to determine the distance of a target from your

boat. When measuring be certain to move the VRM to a point close to the center of the echo image

on the screen.

Fig.2-11 VRM

EBL (Electronic Bearing Line)

This straight-line marker can be rotated in any direction centered on your boat's position. Use the

EBL to indicate the advancing direction of your boat and its relative angle with a target.

Fig.2-12 EBL

VRM

Echo

0.75

0.25

VRM

0.75

0.25

EBL

Echo

EBL

Equal intervals