ABOVE HYDROPHONE 



200 N. M. RADIUS 



400 N. M. RADIUS 



600 N. M. RADIUS 



800 N. M. RADIUS 



0.3 

 0.2 

 0.1 

 0.0 

 -0.1 



0.4 



0.3 



O 0.2 



< 0.1 



0.0 



-0.1 



0.5 



0.4 



y 0.3 



PERIOD OF HIGHEST FREQUENCY 

 OF OCCURRENCE OF 20-C/S SIGNAL- 

 MINIMUM N = 107 



PFRIOD OF LOWEST FREQUENCY 

 OF. OCCURRENCE OF 20-C/S SIGNAL" 

 -MINIMUM N = 106- 



PERIOD OF HIGHEST FREQUENCY 

 OF OCCURRENCE OF 20-C/S SIGNAL- 

 MINIMUM N = 61 



0.2 



0.1 



0.0 



-0.1 



0.4 



0.3 



0.2 



0.1 



0.0 



-0.1 



-0.2 



10 12 16 20 25 32 40 50 63 80 100 126 160 200 250 320 400 

 FREQUENCY, C/S 



Figure 8. (Continued). 



18 



