Aft ballast tub and light for TV cameras 



complete tub by opening the holding magnetic circuit. The 

 tubs are each filled with 8 tons of steel shot. Located at 

 the bottom of each tub is an orifice surrounded by an elec- 

 tromagnet. When the magnetic circuit is energized, the 

 shot is held in the orifice and cannot flow. When the cir- 

 cuit is turned off, the shot is no longer magnetized and is 

 able to flow. The magnetic valve in each of these circuits 

 is double-wired to prevent accidental loss of the tubs 

 through wire failures. An arrangement of pins, turn- 

 buckles and gates mechanically secures the system during 

 nonoperating periods. 



Closed-Circuit Television 



The closed -circuit television system allows an expan- 

 sion of the viewing area at both the sea floor and in mid- 

 water. The vidicon tube camera unit, designed to withstand 

 over 16, 000 psi, is located beneath the entrance tube of the 



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