echo sounder

音标发音

Use echo sounder frequently when passing shallow water.
通过浅水域时，要常用回声仪测深。
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The echo sounder is now gradually out of use in navigation, because it has many errors.
回声测深仪在导航仪器中的地位在下降，其原因是它存在着较多的误差。
A multi-channel data acquirement and process system was developed to meet the need of the portable echo sounder in the dissertation.
本论文针对某便携式测深仪的需要，设计开发了一种多通道的数据采集和处理系统。

a piece of equipment, especially on a ship, that uses sound waves to discover water depth or the position of an object in the water

a navigation and position-finding device that determines depth by measuring the time taken for a pulse of high-frequency sound to reach the sea bed or a submerged object and for the echo to return