Radio age research, manufacturing, communications, broadcasting, television (1941)

TELEVISION CAMERA OPERATOR POINTS THE SENSITIVE ICONOSCOPE THROUGH NOSE OF PLANE TO PICK UP TERRAIN BENEATH. RIGHT: DIAGRAM SHOVT- ING HOW AIRBORNE TELEVISION SYS- TEM WOULD BE UTILIZED IN AN AM- PHIBIOUS OPERATION TO TRANSMIT SCENE OF ACTION TO COMMAND POSTS ON SHIP OR LAND. The Block television unit pro- duces 40 frames a second in sequen- tial scanning, with 350 lines on the receiving screen. Its transmitter has a peak power output of 60 watts at 264 to 372 megacycles, and spe- cial transmitting antennas have been designed for each of its 10 workable channels. NBC began work on the Ring System in 1939, and had succeeded in testing airborne transmission and reception before the war halted commercial research. The Navy be- came interested in the project in 1942, and in 1943 NBC installed a unit in a Navy plane for experimen- tal purposes. Tests Made Over Washington In tests over Washington, D. C, last July, Ring showed its capabil- ity of transmitting high quality television pictures over a 200-mile radius from an altitude of 22,500 feet. Even at dusk, it was able to observe movements of traffic and recognizable landmarks. The Ring equipment employs two cameras, one in the nose and one in the waist of a plane. Ring uses interlaced scanning such as that in commercial televi- sion broadcasting. But even great- er resolution is achieved, it was said, by reducing the field fre- quency from 60 to 40, and the frames from 30 to 20 a second. This enables production of 567 lines on the receiver screen, as compared with 525 lines in commercial tele- vision. The Ring transmitter pro- duces a peak output of 1.4 kilowatts at 90 or 102 megacycles and a spe- cially designed antenna gives uni- form radiation in all directions from the plane. "Walkie-Lookie" is a Prospect General Sarnoff, who is Chair- man of the Board of the National Broadcasting Company, said that he foresees airborne television opening the way for coverage of events with instantaneous trans- mission of eyewitness views at the scene and at the exact time of their occurrence. This coverage can in- clude fires, floods, train wrecks or other happenings of public interest and, he added, the way is opened for development of the "walkie- lookie" — a light-weight, portable television camera with which a re- porter might cover street scenes as readily as he does now with a news camera. 0. B. Hanson, Vice President and Chief Engineer of NBC, described the Ring development as "a major pioneering achievement which greatly enhances television's flexi- bility." Mr. Hanson said the work on the Ring system was conducted under the direction of Robert E. Shelby, NBC Development Engineer, G. M. Nixon, Assistant Development En- gineer, Harold P. See, senior tele- vision supervisor, and others in- cluding F. J. Somers, L. R. Moffett, A. L. Hammerschmidt, W. L. States and A. E. Jackson of the NBC en- gineering staff. Credit for developing the Block system went to Dr. Zworykin, for originating the idea; R. D. Kell, of RCA Laboratories Division, and W. J. Poch, RCA Victor engineer, for advance developments; Merrill Trainer, David Cole, Anthony Wright and Kenneth Chittick, RCA Victor engineers, for product and design; and Otto H. Schade, Dr. R. B. Janes and C. E. Haller, of the RCA Tube Division, for electron tube development. Navy personnel who assisted greatly in the development of the two airborne television systems in- clude: Lieutenant Commander For- rest Griffiths and Lieutenant W. E. Thorp, electronics design engineers of the Bureau of Aeronautics, and R. S. Taylor, civilian Navy engi- neer, who assisted in Block tele- vision arrangements for this show; also Commander T. W. Chew and C. L. Stec, of the Special Weapons Section, Electronic Division, Bureau of Ships. [RADIO AGE 5]