TEINFIDENTIAU PART II], CHAPTER 8 8.15 The submarine cable program cost approximately $2 million for Operation HARDTACK. Two new 26-pair cables were in- stalled around both atolls to provide required pairs for the TG 7.1 timing and firing mission. Additions were made to the telephone cable plant to provide a minimum of 16 pairs at most off-island locations. Studies indicate that it costs from $14 to $% million to maintain the submarine cable system for each operation. TG 7.5 is considering microwave to back up and eventually replace major submarine cable runs utilized to provide communications services. TG 7.5 has also recommended that TU-5, TG 7.1, conduct tests to determine the feasibility of eventually replacing the cable timing and firing system with microwave. Microwave has ;roved dependable in telephone company commiunications and tele- vision applications and is portable to meet the changing requirements of test programs. 8.16 Augmentation of the Sites Elmer-Fred cable plant was accomplished byinstalling JTF-Seven-furnished telegraph carrier equip- ment to derive additional teletype quality channels. Installation of JTF-Seven microwave provided the required additional telephone channels. and back-up to the submarine cable plant. Both of these facilities functions] as designed, providing a high grade of communications service. MOBILE RADIO SERVICE 8.17 TG 7.1 was provided the following commercial VHF mobile type communications networks at a cost of approximately $200,000: Command Net. ..... Both Atolls TU-4 (Sandia) Net... Both Atolls Rad-Safe Net... 0.2... Both Atolls TU-1 (LASL) Net...Eniwetok Atoll TU-2 (UCRL) Net... Bikini Atoll Administrative Net. Bikini Atoll 8.18 In many cases, these radios paralled dial telephone service at Eniwetok Atoll, and in other cases radios on several different nets were installed in an office to supplement tele- phone service. The number of mobile-type installations was limited. Traffic studies taken under varying operationa! conditions revealed that only a small percentage of the system capacity was utilized. 8.19 VHF-FM tactical-tyvpe military radio equipment (AN,VRC series), on loan from military sources. was installed in TG 7.5 Boat Pools, TG 7.5 Air Dispatcher nets, and TU-3, TG 7.1 nets. Approximately 200 units were installed, mostly afloat. These units pro- vided a flexible means of communications, be- cause they could be pretuned to operate on several different nets. All nets were considered adequate. INTERFERENCE DETECTION SERVICE 8.20 Since a considerable portion of the scientific diagnostic data was obtained through the use of microwave telemetry, it was of prime importance that these channels be protected from interference by radar and other radio sig- nals. At Site Elmer, a military-furnished interference measuring and locating set was installed in REDWING Station 1518. This installation protected the telemetry circuits located on the adjacent 300-foot tower. A similar installation. made in Building 204, Nan, was transferred to Johnston Island during June. Portable units covering 0-300 megacycles were operated at both atolls, as required. This equipment was utilized to locate radio interference to any authorized radio facility. The interference detection team identified the offending signal, pinpointed its location, and advised JTF-Seven for regulatory action. 8.21 Considerable difficulty was experienced in bringing the older type of equipment up to satisfactory operating standards. The equipment furnished to protect the microwave telemetry lacked the sensitivity and operating efficiency of later model equipment. TG 7.5 is investigating the availability of commercial-type interference-detection equipment; it is planned that such a system mounted in trailer will be procured for use in future Nevada and Eniwetok programs. 8.22 conan m nnn nnnen on oe SUBMARINE CABLE SERVICES NEWSREEL OPERATION Although the original delineation of TG 7.5 communications responsibilities with respect to the transfer of the TEAK and ORANGE events to Johnston [sland was very minor, requirements increased as program planning developed. A telegraph circuit was esta- blished between Johnston Island and Site Elmer to handle traffic during the initial entry until the projected military voice circuits were esta- blished in May. A harbor control station, using HF and VHF radio equipment, was established to handle marine traffic. 8.23 Approximately 25 VHF-FM-VRC-18 type radio units were installed and maintained to support TG 7.1. Ship-shore radiotelephone service was provided the USS BOXER by installing AN/’TRC-24-type equipment and telephone carrier to provide four voice channels. In mid-June. a requirement was received to provide and install single side-hand HF transmitters and receivers for a count-down circuit covering a 90degree sector between Johnston Island and the Hawaiian Islands. Emergency procurement action was initiated by the Contractor’s Los An- geles Office, and the equipment was purchased, Page 58 G!