A Display System for an Acoustic Radar

The facsimile and other display systems used with acoustic radars do not perfectly answer the requirements of real time soundings, principally because of the low pulse repetition frequency of the sounders. The survey of the capabilities and limitations of these apparatus led to develop a new device using a length and thickness modulation - L. T. M. system - of the trace on a storage C. R. T. monitor. This system, without mechanical parts, joins the advantages of the oscilloscopic methods - easy triggering of the sweep. and no maintenance - with those of the facsimile - real time display, possibility of getting paper copies. The main characteristics of the L.T.M. system are given as well as pictures of acoustic soundings thus obtained.