Simrad NX40, Руководство по установке и эксплуатации

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Simrad NX40/45 Installation and Operation Manual 36
CAUTION
!
!
CAUTION
DANGER
WARNING
Use the automatic
Cruising or Fishing modes
when learning to use the
unit or when travelling at
speed.
9-1 Using the unit
The unit uses a echosounder transducer attached to
the hull. The transducer generates an ultrasonic pulse
(sound that is above the hearing range of the human
ear), which travels down towards the bottom at a speed
of about 1463 m/s (4800 ft/s), spreading out into a
cone shape.
When the pulse meets an object, such as a fish or the
bottom, it is partly reflected back up towards the boat
as an echo.
The depth of the object or bottom is calculated by the
unit by measuring the time taken between sending a
pulse and receiving the echo. When an echo has been
returned, the next pulse is sent.
The unit converts each echo into an electronic signal,
shown as a vertical line of pixels.
The most recent echo appears on the extreme right
of the window, with the older echoes being scrolled
towards the left, eventually disappearing off the
window.
The scroll speed depends upon the water depth and
scroll speed setting.
The appearance of echoes shown are affected by:
The unit settings. •
Echoes (different fish types, different bottom types, •
wrecks and seaweed.
Noise (water clarity and bubbles.) •
Cruise, Fishing and Manual Modes
The unit has three echosounder operating modes:
• Cruising mode: Use this when on the move. The
unit automatically adjusts its settings to compensate
for water clarity and to display the bottom.
• Fishing mode: Use this when fishing. The unit
automatically adjusts its settings to compensate for
water clarity and to best display fish, the bottom and
other details.
• Manual mode: Use this to fine-tune the unit
settings by hand. Best results are often achieved
in manual mode, but practice and experience are
required to obtain the optimum settings for different
conditions.
Echosounder fishfinding: Introduction 10