configure a system including automatic corrections for gain, speed variation, 

 and slant range by purchasing the necessary options. Other features available 

 include : 



a. Digitally controlled dry paper display. 



b. User friendly operating panel with many presets and battery 

 backup of memorized settings (in case of power interruption) . 



c. Capable of simultaneous 100- and 500-kHz side scan and 3.5-kHz 

 subbottom profiler data collection. 



d. Flexible for adding other processing/convenience modules. 



38. The modularity of the KLEIN equipment can be an advantage or a 

 liability, depending on the user's perspective; from the authors' viewpoint it 

 is somewhat cumbersome for coastal engineering work. Also, the analog tape 

 data recording option is less convenient and reliable than the digital car- 

 tridge recorder available for the EG&G system. However, this system should 

 perform in the manner of all previous KLEIN instruments and can be used in the 

 coastal environment. 



KLEIN Models 520 and 530 Analog SSS 



39. The Klein Models 520 and 530 SSS have been manufactured since 1978. 

 The Coastal Engineering Research Center, US Army Engineer Waterways Experiment 

 Station, owns a Model 530 and has used it successfully on several coastal 

 structure inspection projects and continues to use it. A number of US Army 

 Engineer Districts also own these SSS models. The primary limitation of the 

 Models 520 and 530 SSS is the operator skill required to adjust the approxi- 

 mately 24 knobs associated with variable gain, print intensity, etc. In addi- 

 tion to being considerably more difficult to tune initially, the instrument 

 requires frequent adjustment to obtain the optimum image, particularly when 

 operating in the changing environment near coastal structures. 



40. For occasional users of SSS, it is probably not cost effective to 

 replace the older analog models such as the 520 and 530 with the new digital, 

 self- tuning SSS. Whenever a competent operator is available, the tuning dif- 

 ficulties, wet paper, a hea-vy and bulky receiver, and less precise analog 

 recording capabilities can probably be overlooked. Only those districts con- 

 sidering a new SSS or expecting to perform a significant amount of detailed 

 inspections should invest in a digital SSS. 



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