Broadcasting (Oct - Dec 1949)

iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii^ WU's Telcoarc Lamp THE answers to some of television's more stubborn lighting problems may be provided by a new high-power, high-intensity electric light, named Telcoarc described Friday by W. D. Buckingham, assistant to the electronics research engineer of Western Union Telegraph Co., in a paper presented before the Society of Motion Picture Engineers convention in Hollywood. Light source of the new lamp, which operates in the open air and not in a glass bulb, is a pool of molten zirconium two-tenths of an inch in diameter. Maintained at a temperature near 6500 F, this source is one-eighth as bright as the sun, Mr. Buckingham said. The light, which has a brightness 20 times that of the tungsten filament lamp, totaling 20,000 lumens with a maximum brightness of 130,000 candles per square inch, is an outgrowth of WU's wartime research in military communications, he reported. Asked about the uses of the Telcoarc in TV, Mr. Buckingham said that it will probably be used chiefly for illumination. However, he added, the new light may well be used for the projection of background lighting and scenes for sudio shows. When a 5 kw tung NeW' Technical Developments for TV (Report 81) Telcoaic's small electrode which can be rejolaced when exhausted. sten filament lamp was used for such projections, so much heat was generated that the slides had to be watercooled, he stated. The same light, 2,000 lumens, can be produced by a 1 kw Telcoarc lamp, he said, and comparatively so little heat is produced that a slide can be left in for an hour without harm. The Telcoarc will be "ideal" for flood and spot lighting and searchlights. Dr. Buckingham stated. He predicted that it also will have wide Mr. Buckingham examines the light from the Telcoarc through a dark filter. Working parts of the Telcoarc lamp. * * * medical and scientific use and will be of special importance to color photography. No prices have been set for the Telcoarc lamps as yet, but they will be priced competitively with the tungsten lamps, he said. Manufacturing plans also are unsettled, but it is expected that WU will license lamp companies to produce them rather than enter this field itself. CBS-B&B Projector FOR reportedly the first time in television history, last week during the telecast of This is Show Business, action films were shown on the screen of a studio television set which appeared along with the announcer demonstrating it to home viewers. Heretofore when a video set was presented, the picture inserted in the tube frame was a "still." CBS in collaboration with the Benton & Bowles television department, built a special projector geared down to synchronize with the phasing and pick-up rate of the television camera. The projector slowed the film from 60 frames per second to 30 frames so that the material could be inserted in the tube space of a demonstrated Crosley television set, and the image of the set in its entirety was picked up by the TV camera, giving the effect of another video show being retelecast by the studio camera. As the announcer turned the switch on the Crosley set, the projector inside the set started simultaneously. Herb Leder, director of TV for Benton & Bowles and Bill Valle, technical director of TV for the agency, developed the technique along with Fred Reinhart and John De Mott of CBS. This Is Show Business is sponsored by Avco Corp., Crosley Div. Projectall Dissolve Unit TRESSEL TELEVISION Productions, Chicago, which manufactures the Projectall, plans to release, within two weeks, a new attachment which will make automatic dissolves possible. George Tressel, company president, said the new mechanism adds no bulk to the Projectall as it fits on the back of and in the instrument. It includes a second aperture, lighting system and cooling system, enabling immediate dissolves and use of more title cards, he said. Sergei Fomenko, firm's design engineer, returned recently to Chicago after a two-week trip to northeastern TV stations which telecast Projectall news, time, temperature, music and advertising. He exhibited a working model of the new attachment and explained its operation. All Projectall-injstalled TV stations are expected to use the new device, Mr. Tressel said. Rectangular TV Tube RECTANGULAR TV tube, designed to be used in a cabinet small in proportion to picture size, is ready for mass production at American Structural Products Co., Toledo. Firm is a subsidiary of the Owens-Illinois Glass Co. The rectangular shape will give tube makers "an ideal glass tube" for 100% reception of the transmitted picture, according to Stanley McGiveran, American Structural president. KSL-TV Periscope WHILE covering the Sept. 30, Oct. 1-2 semi-annual conference sessions of the Mormon Church, KSL-TV Salt Lake City employed new methods of telecasting. A periscope-like ins t r u m e n t caught the front-view image of the speaker on the pulpit and sent it by reflecting mirrors to a camera built in the Tabernacle basement. Also used was a special platform erected in front of, and a little lower than, the south balcony of the Tabernacle. The telecast was the first of general sessions in the history of the Church. Receivers were set up in the Assembly Hall on Temple Square for the benefit of overflow crowds, crowds. Page 52 • October 17, 1949 BROADCASTING • Telecasting