美国克莱英公司最近研制成功的590型克莱英数字声纳系统,包括一台海底地形记录仪一台浅地层剖面仪以及电缆、绞车等附件。该设备用单频(100kHz或500kHz)或者双频(100kHz和500kHz)拖鱼。单频拖鱼的功能受到一定的局限,使用单频100kHz拖鱼有较远的探测距离,而分辨率则较低;而使用单频拖鱼探测距离较近,但分辨率则较高。双频拖鱼装有500kHz和100kHz的换能器,它既有较远的探测距离,又有较高的分辨率。双频拖鱼仍用一根电缆与图形记录仪 The recently developed Craley British Model 590 digital sonar system by the United States Craley British Company includes a shallow terrain recorder and a cable, winch and other accessories. The device uses single-frequency (100kHz or 500kHz) or dual-frequency (100kHz and 500kHz) fish. The function of single-frequency dragged fish is limited. The use of single-frequency 100kHz dragged fish has longer detection range and lower resolution, while the use of single-frequency dragfish has a shorter detection range and a higher resolution. Dual-band trailers equipped with 500kHz and 100kHz transducers, which have longer detection range, but also a higher resolution. Dual-frequency fish are still using a cable and graphics recorder