Edgetech 3200-XS, User Manual

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Main System Components
1-7
1.4.2 SB-424, SB-216S and SB-512i Tow Vehicles
The SB-424, SB-216S and SB-512i Tow Vehicles are each designed to operate over a
specific frequency range, and as lower operating frequencies generally require longer
hydrophone arrays and larger transducers, they differ primarily in size and weight. The
SB-424 Tow Vehicle, which is the smallest of the three, operates over a frequency range of
4–24 kHz, followed by the SB-216S at 2–16 kHz and then the SB-512i at 0.500–12 kHz. All
three tow vehicles are shown in Figure 1-4. Each is hydrodynamically stable with the
transducers and hydrophone arrays mounted under an acoustic baffle to reject downward
traveling multiple echoes. These components, along with "spider" cable harnesses and a
preamplifier are enclosed in a two-piece fiberglass shell that is fitted with stabilizing fins
and lead ballast. A hinged U-framed tow bridle is used for towing, and the tow point
location can be adjusted to accommodate different towing speeds and depths. The tow
vehicles are each shipped in a wooden crate.
1.4.3 75-Meter Kevlar Reinforced Tow Cable
The tow cable is a 75-Meter Kevlar
Reinforced Cable that includes three
twisted shielded wire pairs. This
cable, which is shown in Figure 1-3
and is available separately, is used
to connect to and tow the SB-424,
SB-216S and SB-512i Tow Vehicles.
However, because of the weight and
drag exhibited by the larger SB-512i
Tow Vehicle, a separate steel cable
is recommended for towing this tow
vehicle. The steel cable can be
attached to the tow cable. In
addition, to increase the life of the
tow cable, which has a tensile
strength of 650 pounds, a separate
steel cable can also be used with the
SB-424 and SB-216S Tow Vehicles.
The tow cable includes a cable grip for attaching to the tow bridle of the tow vehicle and is
shipped in a wooden crate with the tow vehicle.
Figure 1-3: 75-Meter Kevlar Reinforced Tow Cable