2.9 Measuring Depth to a Fish School
The VRM (Variable Range Marker) functions to measure the depth to fish schools or other echo.
1.Press[ 
]or[
]to place the VRM on an echo.
2.Read the VRM range just above the VRM.
2.10 A-scope Display
This display shows echoes at each transmission with amplitudes and tone proportional to their intensities, on the right 1/4 of the screen. It is useful for estimating the kind of fish school and bottom composition. To turn the
Normal display
