PART IV: DATA COLLECTION AND ANALYSIS 

 Data Acquisibion System/Digital Data Collection 



33. The primary data acquisition system was a Data General Corporation, 

 Westboro, Mass., NOVA-4 minicomputer located in the FRF Laboratory building. 

 The backup system consisted of a WICAT Systems Incorporated, Orem, Utah, 



150 WS minicomputer. Signals from the air temperature and atmospheric pres- 

 sure sensors, the anemometer, and wave gages were routinely sampled four times 

 per second for 20 min every 6 hr beginning at or about 0100, 0700, 1300, and 

 1900 hours Eastern Standard Time (EST); these hours correspond to the time 

 that the NWS creates daily synoptic weather maps. During storms, hourly data 

 recordings were made. Prior to collection, each gage signal was first ampli- 

 fied and biased to ensure a 0- to 5-V range. 



34. Data were recorded on nine-track magnetic tapes having the follow- 

 ing format: first, two header records of information were written, which in- 

 clude (a) the sensor identification number; and (b) the date, time, cali- 

 bration, and signal bias factors, followed by 13 records of data for each 20- 

 min recording interval. Each data record contained 384 data values in a bi- 

 nary format, such that each value represented the computer units corresponding 

 to the instantaneous voltage output of the sensor. The above sequence of 15 

 records per file was repeated for each sensor and recording interval until the 

 data tape was filled, a total of 600 to 700 files per tape. 



Meteorological Data Collection 



Maximum and minimum thermometers 



35. High and low temperature values were read daily directly from 

 the instruments and represent the extreme temperature values since the last 

 reading. 



Microbarograph and rain gage 



36. Each instrument used for monitoring the meteorological conditions 

 at the FRF was read and inspected daily. For those instruments with analog 

 chart recording capabilities, (a) the pen was zeroed (where applicable); 



(b) the chart time was checked and corrected, if necessary; (c) a daily read- 

 ing was marked on the chart for reference; (d) the starting and ending chart 



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