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

UHF Converter for TV {Continiud from page 1J> President and General Mananer of the RCA Victor Division. In the statement, Mr. Buck al^so assured owners of two million RCA Victor television sets that, while such service from UHF stations is not expected before late 1952 or early 19a.S, a simple, high-quality converter will be made available so that telecasts can be received on ultra-hijrh-freiiuency channels with quality comparable to those received from the very-hijrh-frequency bands now in use. Pointing out that every current television set, regardless of make, will require some modification to receive a UHF signal, Mr. Buck added: "Our experiments at Bridgeport and in the laboratory have conclu- sively proved to us that the best way of accomplishing UHF recep- tion on existing receivers, when UHF arrives, is by means of a con- verter. "No receiver currently manufac- tured has provision for conversion to UHF without additional cost for e<iuipment and installation, nor- mally including the addition of a special outdoor antenna." Other points made by the RCA \ictor executive were: Final approval of the new UHF channels as yet has not been given by the FCC. .\ssignments of the new channels lu stations cannot be made until such final approval has been given by the FCC. Aside from delays which may be caused by shortages of critical materials, the time cycle required for construction and installation of transmitting equipment, and erection of transmitting antennas, is such that large-scale telecasts of UHF will not commence before late 10.52 or early 1953. When UHF broadcasts commence, . RCA Victor, and, it is assumed, other manufacturers, will have available an adequate supply of high-quality converters for present VHF receivers assuring full-band reception of all the UHF channels without sacrificing any of the pres- ent VHF channels. Dr. Zworykin Receives I.R.E. Medal of Honor Dr. Vladimir K. Zworykin, Vice President and Technical Consultant of RCA Laboratories, Princeton. N. .1.. received the 1951 Medal of Honor, highest award of the Insti- tute of Radio Engineers, at the organization's annual banquet at the Waldorf-Astoria Hotel, in New- York City on March 21. He was cited "for his outstanding contri- butions to the concept and develop- ment of electronic ai)paratus basic to modern television, and his sci- entific achievements that led to fundamental advances in the appli cation of electronics to communica- tions, to industry, and to national security." In accepting the award, Dr. Zworykin urged his fellow radio scientists to make electronics serve mankind through medicine. "The range of problems in medicine to which electronic methods could be api)lied," he said, "is remarkably broad, embracing both diagnosis and therapy. Increased emphasis on this objective would enhance the service of our profession to man- kind and broaden the base of the electronics industry." Tri-Color Tube Details Revealed C"^OMPLET^: information on the ^ procedure to follow in building the tri-color television picture tube developed by the Radio Corporation of America for the reception of all- electronic, compatible color televi- sion, has been made available by RCA to other television receiving tube manufacturers. This tube, acclaimed a "miracle of science" and recognized as vital for the complete development of a practical, all-electronic color tele- vision receiver, was first demon- strated publicly on March 29, 19-50. A week later it was shown officially to members of the Federal Com- munications Commission. Details disclosing for the first time the full technical characteris- tics and construction of the tri- color tube were contained in a bulletin prepared and issued by the Industry Service Laboratory of the RCA Laboratories Division. This bulletin was the fourth i.s- sued by RCA making known to other manufacturers its progress and methods in developing an all- electronic, compatible color televi- sion system. Previous bulletins contained circuit details of RCA color television sets, demonstrated for the press and television indus- try in December at Washington, D." C. The latest bulletin illu.strated and described steps that may be taken to build engineering models, simi- lar to the RCA experimental three- gun color picture tube of direct- view type used during the Wash- ington demonstrations. It pointed out that a single-gun tube (one having but one emission source of electrons) may be built on the specifications provided, with relatively few modifications, and that many of the techniques u.sed in making present black-and-white picture tubes also may be employed. One of the steps de.scribed in to- day's bulletin lifted the veil on an achievement which has caused wide speculation in the industry. This was how RCA engineers succeeded in placing 600,000 phosphor dots of the primary colors, green, red and blue, in the screen assembly. These diminutive dots are ar- ranged in groups of three and so positioned that the electrons from each of the three electron guns in the base of the tube always strike the dots of its own color. The phosphor dot groups are so small and so close together that when illuminated by the electron streams they present a continuous, smooth, full-color picture. Manufacture of the tri-color tube, the bulletin pointed out, is divided into two parts: 11» fabrication of a screen assembly which includes an aperture mask and a phosphor- dot plate, and (2) the building of this assembly together with elec- tron guns into a metal envelope to form the finished tube. The tri-color tube may be built in sizes comparable to those of pres- ent black-and-white television re- ceiving tubes. [RADIO AGE 29]