Simrad ce32 mkii, Руководство пользователя

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%CHOSOUNDER OPERATION
The echosounder function of the CE32 MKII determines the distance between
its transducer and underwater objects such as fish, lake bottom or seabed.
It does this by utilizing the fact that an ultrasonic wave transmitted through
water travels at a nearly constant speed of 4800 feet (1500 meters) per second.
When a sound wave strikes an underwater object such as fish or sea bottom,
part of the sound wave is reflected back toward the source. Thus by calculating
the time difference between the transmission of a sound wave and the recep-
tion of the reflected sound wave, the depth to the object can be determined.
The entire process begins in the display unit. Transmitter power is sent to the
transducer as a short pulse of electrical energy. The electrical signal produced
by the transmitter is converted into an ultrasonic signal by the transducer and
transmitted into the water. Any reflected signals from intervening objects (such
as a fish school) are received by the transducer and converted back into an elec-
trical signal. It is then amplified in the amplifier section, and finally, displayed
on the screen.
The picture displayed is made up of a series of vertical scan lines (pings), one
for each transmission. Each line represents a ’snapshot’ of what has occured
beneath the boat. The series of snapshots are accumulated side by side across
the screen, and the resulting contours of the bottom and fish between the bot-
tom and surface are displayed.
3ELECTING ECHOSOUNDER DISPLAYS
The CE32 MK
II
provides four types of echosounder displays: standard, bot-
tom zoom, marker zoom and A-scope. Each display has its advantages and dis-
advantages. Select the appropriate setup for the echosounder display in the
’Presentation setup’ and ’Echosounder setup’ displays, considering current sea
area and target fish.
F
To view the echo display while plotting ship’s route, select the Chartplot-
ter/Echosounder combination display with the key combination: [MENU], [1]
and [1].
#% -+)) %CHOSOUNDER OPERATION #HAPTER
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