Raymarine L470 - Manual (Page 58)

52
Operating Instructions
A-Scope (Bottom Coverage) Mode
On the FishFinder Page the bottom graph is “drawn” after the FishFinder
receives several echoes. This has the effect of showing a record of the
bottom
contour. The A-scope Mode shows raw sonar data directly from the
transducer beam. This gives you a “real time” image of fish and bottom
structure directly below the transducer. (The A-Scope Mode is sometimes
called an “In-Line Flasher.”) This function is very useful in showing the
strength of the echo returned from a fish.
You can reach the A-Scope Mode at any time by pressing the A-Scope
button. Figure 3-14. The left section of the A-Scope Mode shows a
section of the normal FishFinder Page. The right section shows the A-
Scope image.
A-Scope image
The normal FishFinder Page with the White Line feature
enabled (see Fig. 3-4) allows you to tell the difference
between two levels of echo strength. Weak targets are shown
in black, while strong targets are shown in a gray checkered
pattern. The A-Scope image, by contrast, gives you more
detailed information. In the A-Scope Mode,
stronger echoes
A-Scope image
(real time image)
Fig. 3-14
A-Scope
Mode
(half screen)
Fish
indication
A-Scope
display
Normal
display
Bottom
coverage