CHAPTER I!, SECTION 3 The roof section in this area was placed on a 2:1 slope with framing members extending down to the ground to provide track support for the sliding roof panels. These roof panels were released by a mechanism utilizing wire signals to a solenoid for each panel. Handoperated winches were fastened on the roof to reposition the panels. The room was grounded using copper screening on the walls, ceiling, and floor. The floor screen was protected with plywood cover. Collimator Room “‘B” was separated from Room “A” by an open stud partition which had a double door. The wall was used to sup- port the screen of Room “A.” Collimator Room A User-furnished motor generator set was located under a shed roof outside but adjacent to the building. This unit, as well as two com- pressors and two pumpsfor the air-conditioning units, was placed outside to reduce vibration to the building. The electrical power and lighting panels were located on exterior building wall under the same shed roof as the eqipment. A personnel shelter was provided outside the building. The shelter was 5x6x7 feet high and was constructed of re-inforced concrete. About one-half of the building was below grade. It contained only a bench and a light and served as an emergency shelter for two people. “B” was not screened, but it was insulated with Celotex throughout. Hinged-down shutters on the front wall and an 8x14-foot sliding roof panel were included similar to that provided in Collimator Room “A.” The Spectrograph Room 12x17 feet, was located directly behind Collimator Room “B.” It was separated from Room “B” by high, 1-foot-thick concrete wall with high insulated plywood panels above wall above the panels. The wall was only on the Collimator Room side. a 2-foot114-footand stud insulated The wall opposite was not insulated. A door was provid- ed in the wall containing the concrete. Adjoining the Spectrograph Room and Colli- mator Room “B” was the Photometric Room, 10x22 feet, with double-door access to the Spectrograph Room. This room wasair-conditioned, but no insulation was provided. The walls were (Neg. No. W-957-1L) covered with plywood, and the roof rafters were exposed. The room had a 6-foot double-door entry from the outside and a workbench, 22 feet Figure No. 2-72. Sliding Hatch Mechanism — Stations J-1030 and J-1810. long. STATION: J-1711 Located behind Collimator Room “A” and adjacent to the Spectrograph Room was Elec- SITE: Johnston Island USER: LASL PURPOSE: Generator Shed and Trailer tronics Room “B,” 12x15 feet. The room was grounded by use of aluminum sheet placed over plywood for the floor and three walls and over Celotex insulation for the ceiling. The fourth wall utilized copper screen on open studs to complete the ground system. The Electronics Support Room was 10x12 feet and was also located behind Collimator Room ‘A” but adjacent to Electronics Room “B.” No insulation was provided on the walls, but the ceiling utilized Celotex. Entry was pro- vided from the outside of Collimator Room ‘“A”’ and Electronics Room “B.’ The room was air- conditioned with large units necessitated by the heat load from electronics equipment; although these units were located in the support room, they exhausted into Electronics Room “B.” Since the wall separating the two rooms was screened on open studs, both rooms were cooled. A small workbench was also provided in the room. Page 134 PARTICIPATION: J-40, J-41 DESIGN PSI: None CONSTRUCTION: 5-2-58/7-7-58 A User-furnished trailer and three antenn: were all placed in line, and a User-furnishe motor generator set was located in a shelter. Two 100-kw, 3-phase generators supplied the power. The motor generator shelter was 8x8: feet high and of wood construction. The thr trailer receptacles provided were located on the exterior of the building. Instrument power in the trailer was supplied from the motor generat set which in turn was supplied power from t : 100-kw generators. User-furnished starter and regulator were installed for the motor generator set.