Interphase Color Twinscope, Руководство по эксплуатации

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In addition to its ability to electronically steer an acoustic
beam, the phased array has other advantages over fixed-beam
technologies, such as: allowing the user to adjust the
transducer beam width, to scan large areas limited only by the
physics of the speed of sound in water (5,000 feet/second), and
the ability to provide nearly real time or live action underwater
views.
When operating, the Twinscope converts a small amount of
electrical current from your battery into ultrasonic sound
pulses, which are then fed to the phased array transducer.
These acoustic pulses travel out from the transducer in a cone
shaped pattern, called the cone angle. When the sound pulse
strikes an underwater object, it is reflected back (echo return),
received by the transducer and converted back into small
electrical impulses. These impulses are amplified, then
displayed as an image on the LCD screen.
The strength of the echo, the depth of the object, and the angle
of the transducer’s beam all affect how the image appears on
the display. Other factors which affect the image include boat
speed relative to the movement, position of the underwater
target and the number of objects reflecting pulses back to the
Twinscope .
The Twinscope’s forward looking display is new and learning
to properly interpret scanning sonar takes both patience and
experience, but once mastered, the
Twinscope can offer
tremendous operational advantages over conventional fixed-
beam depth sounders. It is also important to realize that while
the
Twinscope shows the bottom in both the forward and the
conventional downlooking mode, the presentations are really
quite different. The forward scan shows a view as the beam
“sweeps” across an arc (just like a radar), while the
conventional downlooking view shows a history of repetitive
soundings packed tightly together.