by a complement of motion picture camera bells and deep-water still- 

 photography systems. There are also facilities for same day film pro- 

 cessing on the Island for a quick look at black and white or color films. 



The commxmications system has several radio frequencies which are 

 assigned for use at SCI and at companion facilities on the mainland. 

 These frequencies are so distributed that they provide reliable long-range 

 and short-range communications under all atmospheric conditions. On- 

 Island communication occupies a main transmitter-receiver building at 

 Station Peak with a backup utilized by several stations through a direct- 

 wire link. 



Available oceanographic instrumentation can provide pertinent infor- 

 mation for any imderwater test program. Among the primary equipments 

 ready for use are Roberts' electric current meters, Savonius-type direc- 

 tion and velocity and recording meters, a portable precise echo-sounder, 

 sound velocity and salimetry meters, optimal transmission meters, elec- 

 tronic thermistors, and oceanographic winches. Supplemental equipment 

 includes items such as a Phleger-sediment corer and bathythermographs. 

 Also, the SCI meteorological station is equipped for complete surface and 

 upper air weather observation. 



Now, the human element of the Ocean Engineering Range is introduced. 

 Underwater projects at SCI that require diving service may draw upon a 

 contingent of three officers and 24 Navy divers (including a medical diving 

 officer and four hospitalmen) assigned to NUC. This group is based at 

 the Long Beach Naval Station and serves requirements at Morris Dam, 

 Long Beach Sea Range, and San Clemente Island. Personnel are rotated 

 between the four areas as the work load requires. Military diving activi- 

 ties at the Island began in 1958 with the inception of Pop-Up Facility 

 installation and have expanded ever since. Nearly 200 man-hours of 

 imderwater work are performed weekly by NUC divers in one of the 

 largest Navy diving efforts in the United States. Diving requirements at 

 the Island include numerous trade skills. Routine work includes periodic 

 inspection and maintenance of sea-cable installations, inspection and re- 

 placement of underwater winch cables, maintenance of the imderwater 

 launcher complex, installation and final adjustment of underwater instru- 

 mentation, photographic work, welding and salvage, hardware search 

 and recovery, heavy-equipment rigging, and observation of experimental 

 submerged equipment for proper functioning. Both scuba and helmet 

 diving capabilities and shore-based and ship-based recompression cham- 

 bers are available. 



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