Interphase Proble Operation Manual page 7

acoustic beam, the phased array has other patent pending
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 Probe 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
Probe.
Please Note:
Learning to properly interpret scanning sonar takes both
patience and experience, but once mastered, the Probe can
offer tremendous operational advantages over conventional
fixed-beam depth sounders. It is also important to realize that
while the Probe 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 the bottom, while the conventional
downlooking view shows a history of repetitive soundings
packed tightly together.
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