How To Interpret The Vertical Scan Display - Furuno CH-500 Operator's Manual

3.3

How to Interpret the Vertical Scan Display

The sound beam is emitted in a vertical half-circle, which forms a sounding area sim-
ilar to a slice of watermelon. This gives the user a better view of the underwater con-
ditions. The bearing of the vertical sounding beam can be selected manually or
automatically.
Port-starboard scan (seabed)
In this example, you can see the echoes of a fish school to the right (starboard) of the
ship. Note that the seabed echo is displayed wider as the distance from the ship in-
creases. This can make it difficult to see fish near the seabed.
Fore-aft scan, passing over a school of fish
Fish school Fish school
Seabed Seabed
In this example, you can see the echoes of a fish school in front of the ship (fore). Note
that the seabed echo is displayed wider as the distance from the ship increases.
Sounding beam's bearing
Bow
Fish school Fish school
Seabed Seabed
3. VERTICAL SCAN MODE
Scanned area
(shaded)
PORT STBD
Fish school Fish school
AFT
OS position OS position
indicator indicator
Seabed Seabed
CSE
SPD
GAIN
TVG LEVEL
DISTANCE
COLOR
FORE
Fish school Fish school
CSE
SPD
GAIN
TVG LEVEL
DISTANCE
COLOR
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