Simrad ES200-7C - REV E, Installation Manual

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Simrad ES200-7C
Retractable transducer
Hull units allowing the transducer to be lowered and hoisted are
commonly used for horizontal looking sonars. When not in use,
the transducer is retracted into a trunk.
The retractable hull unit is more expensive than a blister, but on
vessels with a hull where it is difficult or impossible to install a
blister, it may still be worth while. The principles of a hull unit
with a retractable transducer is shown below.
Vessels without a keel and with a wide, flat bottom is an example
where a retractable hull unit can be the only acceptable method
for bringing the echo sounder transducer below the boundary
layer.
(CD017012E)
B
E
C
D
A
A
Transducer
B
Trunk
C
Transducer
shaft
D Transducer
shaft sleeve
E Keel
24
307120/B