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tripod. Any sharp corners on the cradle should be rounded and 



smoothed for safety. 



The DPG might be better protected against high voltage 

 transients, (i.e., lightning), by bonding the steel armor of the 

 cable to the water-tight instrumentation cylinder at the seaward end 

 and to the ground system of the FRF at the landward end of the cable, 

 (J . Anderson Plumer, Lightning Technologies, Inc., personal 

 conversation) . 



Various configurations of the DPG arms used for differential 

 pressure measurements might be considered for investigative purposes. 

 Intuitively, one might expect that the most effective directional 

 measurements made by the DPG would be for the case of a maximum 

 signal reported by each differential pressure transducer. This 

 requires that the differential transducers be oriented 45 degrees to 

 the wave ray or crest. In this way, the peak signals from each 

 transducer would be of the same amplitude, and for sufficiently large 

 wave activity, above the noise level of each transducer channel. If 

 the incident wave direction at a site was normally distributed about 

 the shore normal, then one might expect the most effective 

 directional measurements to be made by a DPG with its arms oriented 

 A5 degrees to the shore normal. The DPG prototype was placed at the 

 FRF (with little consideration for orientation) such that the x-axis 

 (dPl and dP3) arms and the y-axis (dP2 and dPA) arms are 17 and 73 

 degrees from the shore normal, respectively. Various configurations 



