PART III: INSTRUMENTATION 



18. This part identifies the instruments used for long-term monitoring 

 of oceanographic and meteorological conditions and briefly describes their 

 design and operation. More detailed explanations can be found in Miller 

 (1980). Equipment (i.e. the surveying system) used for collecting other types 

 of data is discussed in Part IV. 



Wave Gages 



19. Five wave gages were operated in 1980 as part of the FRFMA for 

 monitoring wave conditions in the vicinity of the FRF (Figure 2) . These in- 

 cluded a wave staff gage on Jennette's Fishing Pier in Nags Head, N. C, 

 approximately 40 km south of the FRF; two wave staff gages on the FRF pier 

 (one at station 6+20 (hundreds of feet), the other at station 19+00); and two 

 Waverider buoy gages located 0.6 and 3 km offshore. 



Staff gages 



20. The wave staffs were parallel cable types manufactured by the 

 Baylor Company, Houston, Texas, and were designed for an accuracy and resolu- 

 tion of 1 and 0.1 percent full scale, respectively. The Baylor gages required 

 little maintenance except to keep the cables taut and free of anything which 

 could cause an electrical short across them, i.e. fishermen's nets, ropes, 

 biological fouling, etc. Defective parts required replacement; this type of 

 gage (specifically the transducer elements) is susceptible to lightning 

 damage . 



21. The transducer elements were connected to test cables in the labo- 

 ratory and calibrated prior to installation by placing an electrical short 

 between the cables at known distances and noting the voltage output from the 

 transducer. In the field, electronic signal conditioning amplifiers were used 

 to ensure the output signal from the gage was within a 0- to 5-V range. The 

 transducer elements and signal conditioning electronics held their calibra- 

 tions very well; differences greater than 1 percent full scale were unusual. 

 Table 1 shows the dates when calibration/maintenance was performed for the 

 Baylor staff gages. 



22. Since the Baylor staff gages actually sense the water level on the 

 gage, a 20-minute average of the levels measured four times per second can be 



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