>> obviously, we have to wait and see or get evidence of what was heard for how long. is it a very unique sound at a very fixed frequency. and the ticking of a clock. it's very repeatable and very continuous in that way. so even if they heard it partially over the course of 90 seconds, it would -- you -- is it unique to the device itself. obviously there are many things in the water that can generate sound. but this is unique in what it produces. >> the device a chinese ship used is hand held and meant for divers. a news conference is scheduled for the bottom of the hour, 11:30 eastern time here in the united states. our special coverage of what happened to flight 370 continues. if the new pulse signals are real what do they say about