CNN Smerconish April 5, 2014 13:24:00
Oceangraphic gear. we use gear all the time. those are some of the things that come to my mind. again, those could be canceled out if we had more information. >> let me ask arnold carr, you are our sonar expert. what might be triggering this if not the black box? >> it could well be something ship board. a depth sounder. especially longer range, you need a lower frequency that could be down to about 50 kilohertz, which would be within the range of what that hydrophone or device they are using receives. it could just interfere with that signal. the other thing as was just previously said, fishe...
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