音響測深機用航路警報機(日本航海学会第25回講演会)

抄録

The common process of echo sounding is that a pen attached to an echo sounder slides over the recording paper at a uniform speed, marking the times of the transmission of a pulse and the reception of its echo, and the depth of the sea is read off the paper. This method has some disadvantages, the greatest of them being that it requires constant attention during operation and is apt to cause much inconvenience to the ship, especially when she is entering or leaving port. Fishing boats, most of which are insufficiently manned, are always feeling this disadvantage keenly. With a view to remedying this shortcoming, the authors have made an apparatus for tests which will ring a buzzer and light a lamp when the ship comes to a spot of a particular depth.