in a watertight housing with a thirteen conductor cable connecting it 

 to DAS. Special connectors on the lamp housing a I low the cable to be 

 joined or removed while under water. Following is an explanation of 

 how the lights are "read" in terms of octal numbers and then converted 

 to dec ima I . 



For a lamp display such as the synchronous timing lights (Figure 12) 

 the octal count of any vertical column of three lights is given as: 



Col umn 



Octal count 12 3 4 5 6 7 



where "x" indicates a lighted lamp and "o" indicates an unllghted lamp. 



Each column represents an octal digit. The equivalent decimal count 

 of each octal digit is found by multiplying the octal count by the appro- 

 priate factor. The total decimal count is the sum of the individual 

 decimal counts for all columns, as shown below: 



o 



o 



o 



o 



o 



o 



X 



o 



o 



X 



X 



X 



SYNCHRONOUS 



TIMING LIGHTS 



(d i sp I ay of 12 bits) 



Octal count 

 Factor 

 Total decimal count =0x512+ 1 x64+3x 



I 3 

 o3 „2 „l 



+ I X 



Section IV. PROGRAMMING TIME SERIES 



A "program" is a I ist of instructions that enables the computer to 

 read and manipulate input data and to write or print-out the processed 

 data. The programming of time series* to obtain wave spectra and cross- 

 spectra utilizes the harmonic analysis by digital methods developed by 

 Tukey (Blackman and Tukey, 1959) (Munk, Snodgrass and Tucker, 1959). This 

 method is the basis for the development of a versatile computer program, 

 BOMM, which facilitates the manipulation of large numbers of synoptic time 

 series. The following incomplete treatment of wave analysis by digital 

 manipulation is intended only as an outline to aid in interpreting the 

 programmed results from the data acquisition system. The original refer- 

 ences should be consulted for a more detailed treatment of the subject. 



*Since the writing of this manuscript much interest has developed around 

 a more efficient method for performing a Fourier transformation with a 

 digital computer. (See Appendix A.) 



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