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 re...
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