Journal of the Society of Motion Picture Engineers (1930-1949)

taxed the engineering facilities of the system to the utmost. The production portrayed tactical television as it might function in the future. Cameras were concealed in a barn loft observation post, and by utilizing some eighty enlisted men as friendly and aggressor troops, along with tanks and planted charges, it realistically demonstrated how television front line cameras could send information back to division level where it could be analyzed by the Division Commanding General and his staff and acted on accordingly. While this production fulfilled the unit's primary mission of stimulating thinking about the tactical use of television, it also emphasized to the engineer the need for simple, compact portable equipment with a low power drain. In May 1952 the unit participated in several exhibitions including the Armed Forces Day Exhibition at Boiling Field, Washington, D.C. The unit then departed for West Point, where it provided television facilities and was on exhibition for June Week. Closed-Circuit Television Demonstration at NOL The use of short-range closed-circuit television for scientific and plant operation demonstrations is attracting wide attention in many areas today. The 72nd Semiannual Convention of the SMPTE held one meeting in the U.S. Naval Ordnance Laboratory. Since security restrictions and time would not have permitted the members to visit the large wind tunnel facilities, a telecast was arranged through the medium of a closed-circuit television system provided by the Army Signal Corps. The audience of approximately 150 persons was addressed by Dr. H. H. Kurzweg, Chief of the Aeroballistics Research Division, in the NOL auditorium. * Then the program was switched to the wind tunnel building about onehalf mile away. The picture and sound for the telecast from the wind tunnel were transmitted over an interconnecting relay link. The picture was viewed on Supplied by Mary T. Kanagy, Public Information Officer, U.S. Naval Ordnance Laboratory, White Oak, Silver Spring 19, Md. * For auditorium details see D. Max Beard and A. M. Erickson, "Auditorium specifically designed for technical meetings," Jour. SMPTE, 59: 205-211, Sept. 1952. theater projector system and several standard television receivers in the auditorium. Sound was heard through the auditorium sound-reinforcing system and was recorded through the plant sound-recording system. A communication system was set up to interconnect the wind tunnel program director, link transmission truck, link receiver truck, auditorium moderator and the recording facility. Included in the system were extensions to dial phones, special telephone lines and radio transceivers where telephone lines were not feasible. Through television, the audience saw and heard actual wind tunnel operations explained by the Chief of the Design and Operations Division, J. R. Lightfoot. Schematic diagrams were used to demonstrate the essential components of the large supersonic wind tunnels for research and development testing at equivalent air speeds up to five times the speed of sound and of the similar hypersonic tunnel at speeds up to ten times that of sound. The working section of the large Tunnel 1 was kept open to show the nozzle contour and the missile model positioned on its support. Tunnel 2, also a 40 X 40 cm tunnel and identical John S. Auld: Mobile Television System 469