Rocky
Bottom
Soft Bottom
Hard Bottom
Chart Window

USING THE LEGEND 3000 SERIES

REAL TIME SONAR™ / CHART WINDOW

The sonar returns received by the LEGEND 3000 SERIES are displayed along the depth range scale in a REAL TIME

SONAR™ (RTS) WINDOW and CHART WINDOW. The RTS WINDOW

displays new sonar information within the transducer cone in an expanded, easy-to-see format; the CHART WINDOW logs old RTS WINDOW information to show a contour view of the bottom and structure.

Real Time Sonar™ (RTS)

Window

 

RTS Wide “A” scope mode

Real Time Sonar (RTS)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Window

 

 

 

 

 

 

 

The REAL TIME SONAR (RTS)

 

 

 

 

 

 

 

WINDOW shows instantaneous

 

 

 

 

 

 

 

sonar returns from the bottom,

 

 

 

 

 

 

 

structure and fish that are within

 

 

 

 

 

 

 

the transducer beam. The RTS

 

 

 

 

 

 

 

WINDOW updates with new sonar

 

 

 

 

 

 

 

information up to 30 times per

 

 

 

 

 

 

 

second in shallow water (deeper

 

 

 

 

 

 

 

Structure Bottom

 

 

 

water will slow the refresh rates).

 

 

 

Less intense returns

Intense returns

The RTS WINDOW responds to

quickly-changing depths in a

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

way similar to a flasher type

 

 

 

 

 

 

 

 

sonar display. Interpreting

 

 

 

 

 

 

Intense

the RTS information requires

 

 

 

 

 

 

 

 

 

 

 

 

returns

some skill; comparing the

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RTS data with the data in

 

 

 

Fish

 

 

Hard

the CHART WINDOW, however,

 

 

 

Soft

 

 

Bottom

makes the RTS information

 

 

 

 

 

 

 

 

 

 

Bottom

 

 

 

 

easy to understand.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The width of the RTS WINDOW

 

 

 

Less

 

 

 

 

can be adjusted to your

 

 

 

intense

 

 

 

 

preference. Selecting a

 

 

 

returns

 

 

 

 

wider RTS WINDOW shows

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

greater differences between the strength of the sonar returns, although doing this will reduce the amount of history on the display. See CONTROL PANELS for details on adjusting the RTS WINDOW.

When the RTS WINDOW is wide enough, it plots the depth and intensity (amplitude) of a sonar return using horizontal black lines, where line length indicates return strength, and the vertical placement of the lines next to the depth range scale indicates the depth.

When the RTS WINDOW is narrow enough, it plots the depth and intensity of a sonar return using grayscale lines, where the intensity of the sonar return is divided into 16 levels of grayscale, with the most intense returns shown in black, and less intense sonar returns shown as progressively lighter shades of gray. When the view is narrow enough, the combination of the grouping of the lines and the grayscale level helps to identify the bottom composition and structure. The bottom displays as the largest grouping of black horizontal lines, and typically has gray lines underneath. A harder bottom shows less gray below; a soft bottom shows more gray below. Structure appears above the bottom as a cluster of lines with varying lengths and gray shades.

In any view, fish appear as smaller groupings of sonar returns between the bottom and surface. Often, large fish within a structure will show as a strong return within a grouping of smaller returns. When the boat is stationary or

drifting very slowly, the RTS WINDOW can show the movement of the fish through the transducer beam. Moving fish appear as smaller groups of lines that become progressively larger lines, or vice versa. A grouping of lines moving vertically indicates a fish changing depth.

The Chart Window

The CHART WINDOW creates a historical log of sonar returns from stored RTS information. As the boat moves, variations in the depth and sonar return changes are charted to form an image of the bottom contour. The most recent sonar returns are charted on the right side of the window; as new information is received, the older information is moved across the display.

The CHART WINDOW also indicates the composition of the bottom. A hard bottom, such as compacted sediment or flat rock, appears as a dark, thin line across the display. A soft bottom, such as mud or sand, appears as a thicker line that contains a transition from darker to lighter grays. Bottoms made up of many rocks have a broken, random appearance.

Sloped Bottoms

Bottoms having a large degree of slope also present a unique picture. These generally have a thicker black band representing the bottom directly under the boat. Equal areas of gray above and below the black band represent sonar returns from around the boat.

Second Sonar Returns

A second sonar return may be visible if the appropriate depth range is selected. This appears as a depth contour below the main bottom contour, at twice the depth. The second return occurs when the sonar signal bounces between the bottom and the surface of the water, then back again. Some anglers use the appearance of the second return to determine bottom hardness. With a lower gain setting the second return will be more faint, except in areas with a hard

bottom.The LEGEND 3000 SERIES has a unique depth range feature which permits the second return to be visible in any depth range up to one-half the maximum depth of the unit. See MODES OF OPERATION for details.

Structure

The LEGEND 3000 SERIES displays structure, such as submerged grass, brush, trees and wrecks on the bottom. Structure can be distinguished by comparing the area just above and below the main bottom return. Usually structure shows as areas of dark to light gray on top of a dark bottom contour. The appearance of structure is greatly affected by boat speed and direction; to repeat the same image it is often necessary to travel the same speed and direction over the location where the structure was originally located.

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Humminbird 3005 Deep, 3000 Deep manual Real Time Sonar / Chart Window, Real Time Sonar RTS Window, Structure