as an integral part of the Bikini timing system. The installation was com- pleted and operationally checked out in preparation for the scheduled Teak and Orange events. With the cancellation of the Teak and Orange events from Bikini schedule, it was necessary to remove that part of the timing system from the Bikini installation. A redesign of this equipment to provide for ita independent operation was accomplished in the Forward Area, utilizing the spare components of the Bikini and Eniwetok timing systems. The sys- tem was operationally checked out at Eniwetok prior to its shipment to Johnston Island. Late in June 1958 a group of fleld personnel was sent to Johnston Island to start field installation of the timing system, which was installed at Station 70 in Building 6002. Preliminary dry runs started on July 10. Dry runs and special rehearsal tests were continued throughout the Teak and Orange series. A world time rack identical to that used at EPG on the Hardtack series was included in the design of the Johnston timing system to record actual zero time with respect to WWVH. This measurement was obtained through the use of a 10-ke oscillator, driving the world time clock, synchronized to WWVH and located in the control room. The initial flash of the detonation triggered a fiducial marker on the roof of the CP. This in turn stopped the clock and produced a photographic record of the clock face at zero time. Voice-time announcements were made from a script by the timing system control operator, referencing the timing sequence indicators. These announcements were transmitted to the remote stations on 153.89 Mc, 243 Me, 7411 ke, and 1468 kc, In order to transmit timing signals to the two RB-36 experimenter stations, a radio timing system was provided. This system was synchronized to the master timing system and transmitted various tone frequencies to radio receivers located aboard the RB-36's, which in turn activated equipment at the station. Both ac and de type Blue Boxes were used on both events to provide experimenters with a zero signal of millisecond accuracy. The following timing signal sequence was provided for the Task and Orange events: Teak Orange —60 min ~30 min —15 min -5 min —170.3 sec, lift off ~165.0 sec —151.4 sec —137.2 sec —131.6 sec ~76.2 sec —70.0 sec ~66.6 sec ~60.0 sec —57.8 sec -51.4 sec —60 min —30 min —-15 min -—5 min —153.8 sec, lift off —145.0 sec —110.0 sec -—98.0 sec —95.5 sec —66.6 sec -—60.0 sec —43.0 sec —40.6 sec -15.0 sec —5.0 sec 125