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SAMPLE RECORDING
The ideal location for the first "in the water" tow test is in a calm body of water 20 to 30 foot deep. It
could be in a lake, slow moving river, in a harbor, or a bay area of the ocean.
Running the side scan is a full time operation, at least during the learning phase. It is recommended
that one person run the boat while the other operates the side scan.
Unless you have JW Fishers Ultra Bright “Splash Proof” PC, viewing a computer display on a bright
sunny day can be very difficult. Also operating out of an open boat, with splashing water and spray,
could cause serious damage to the computer. Take the necessary precautions to protect the
computer.
Cable up the system and apply 12 vdc to the Sonar Processor (120 vac power from ship power, or
from a small gas generator set, can be used with the optional 120 vac to 12 vdc wall charger). Do not
power up the Sonar Processor at this time (Computer
must be powered
up and running first).
1) Install the tow arm on the fish, fish will not tow correctly without it.
2) With the boat underway 1-3 kt, lower the fish over the side. Let out enough cable so that the fish
is about half way down to the bottom. Position the cable so that it is not running next to the motor
(electrical noise from the ignition). Be careful not to run the cable near the boat’s propeller. If you
are operating the fish close to the prop wash, the display will not show an image from that side
of the fish.
3) If you are operating in very shallow water, 7-10 ft, there is nothing wrong with towing the fish just
below the surface (2-3 ft of cable let out - stay away from prop wash). In this situation you should
be able to operate in the 10 and 25 meter ranges. Because the fish is so close to the bottom, you
will not be able to operate in the longer ranges. The rule of thumb is that the distance the fish should
be towed off the bottom equals 10-15 % of the Range setting. It is
critical
that the fish is not too
close to the bottom (will not get a picture of the bottom), or not too far off the bottom (will miss
targets below the boat). The fish is at the correct distance off the bottom when there is
approximately 10 to 15% of space between the start of the image and the bottom return. See
drawing below. Note: If you are in shallow water you may also see a surface return printed (a
second line printed). The shaded area in the ruler represents 10-15% of the range. The bottom
return should occur in this general area.
Bottom return
Start of Print
Range Ruler
10-15% Area
Bottom return
with bottom
trace active
Surface return
Содержание SSS-100K PC
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