echo depth sounder

基本解釋

When passing One Fathom Bank, check the depth and variable sand waves below the sea level all the time by echo sounder.
通過(guò)一托淺灘時(shí)，要一直測(cè)深校時(shí)水深及海麪下多變的沙紋。
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Echo Sounder is a kind of acoustic measuring depth equipment, which can measure depth with the time between transmitted wave and echo on condition in which the speed of ultrasonic is fixed.
廻聲測(cè)深儀是用來(lái)測(cè)量水深的一種聲學(xué)測(cè)量設(shè)備，其以水中超聲波的傳播速度爲(wèi)確定條件，利用發(fā)射波與反射廻波時(shí)間差來(lái)測(cè)量水深。