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CHAPTER V 



LABORATORY DEVELOPMENT, CALIBRATION, AND TESTING 

 OF THE INSTRUMENT 



A. Introduction 



Some modifications to the instrument were made during the 

 fluid back-filling of the sensors. These changes, as well as the 

 static bench calibration of the DPG instrument are documented and 

 discussed in this chapter. The preliminary wave-tank tests carried 

 out at the Coastal Engineering Research Center (CERC) , Fort Belvoir, 

 Virginia, are also described. 



B. Fluid Back-Filling the Sensors 



System Modifications 



Certainly the most difficult problem encountered during the 

 assembly of the DPG was the fluid back-filling of the sensing 

 diaphragms. The frustration and numerous failures during the very 

 intense six-week period of back-filling attempts led to two changes 

 each of the type of fluid and tubing used. 



