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Color TV, Conversion and Power Tubes

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Color TV, Conversion and Power Tubes Electron Tubes: A Constant Challenge When the history of our time is analyzed in future centuries, I feel certain that communications will be singled out as the key factor in making possible the "one world" concept-the basis for man's best hopes for the future. RCA's business is communications, and the people of our Lancaster plant have been a strong link in the development of modern systems through which men ex- change ideas and convey information. Lancaster contributed to the success of the rapidly growing television indus- try by establishing the first automatic high -volume production facilities for black -and -white picture tubes immediately following World WarII. This was a major milestone in industrial progress. Later, during 1954 to 1961, Lancaster built the first automatic high -volume production facilities to produce shadow -mask color picture tubes. The worldwide industry was skeptical about the practicality of the shadow - mask precision tolerances and complexity. Lan- caster effort proved to be so successful that the H. R. Seelen entire industry has adopted the design and fol- Division Vice President and General Manager lowed RCA's pioneering leadership. Color tele- Television Picture Tube Div. vision was one of the major growth industries of Electronic Components the 1960's. To the engineer goes the credit for the indispensible design of the tube and the tube processing equipment. And yet all that has gone before is only a fore- runner of communications systems still waiting to be developed. Some systems will incorporate computers; some will, perhaps, have solid-state display panels; but without doubt, whatever their nature, the engineers at Lancaster can be ex- pected to play a key development role. The Lancaster operation is an ultra -modern industrial and engineering com- plex producing a wide variety of electron tubes for a myriad of exciting and important applications in many fields of modern technology; for example, new medical diagnostic techniques; night vision employinglight from the stars as the only source of illumination; power amplification for linear accel- erators used to probe the secrets of the atom; surveillance satellite cam- eras used to better identify the natural resources of the world,just to name a few. The advent of solid-state devices and technologies which was reputed to sound the death knell of tubes has, in fact, accel- erated the growth of the industrial tube business. Combining the older tube technologies with new solid-state knowledge has advanced the fields C. H. Lane Division Vice President and in which electronics participate and we at Lan- General Manager caster look forward to many new advances in Industrial Tube Division the tube art. Electronic Components At Lancaster, the engineer can pursue his profes- Our Cover The three tubes superimposed above the engi- sional career in an amazing number of fields neering scene on our cover are but a small sam- ranging from mechanical design to new optical ple of the myriad tube types designed and pro- techniques. The Lancaster Plant is unique in the duced by the RCA Lancaster facility. Yet, these the three tubes-a color TV tube, an L -band module, range of professional skills demanded by and an image orthicon-set the theme for this products designed and manufactured here. No issue by representing the three principal areas of where is the engineering challenge so varied or engineeringcompetenceat Lancaster:color, power, and conversion tubes. The engineers work- the opportunity for professional recognition so ing at the image isocon test set are E. M. Mussel - great. The engineer is limited only by his own man (seated) and 0. Choi, both of RCA Lancaster. ambition and aspirations. Photo credit: Tom Cook, RCA Laboratories. Contents Papers Milestones in color -picture -tube development H. R. Seelen 2 Development of cathodoluminescent phosphors A. L. Smith 5 Gases and getters in color picture tubes Dr. J. C. Turnbull, Dr. J. J. Moscony, A. Month, J. R. Hale 10 Colorimetry and contrast performance of color picture tubes G. M. Ehemann, W. G. Rudy 14 Autotest-automatic production -test and process -control system for color picture tubes 18 W. E. BahIs, F. C. Fryburg, A. C. Grover, J. F. Stewart, N. A. Teixeira, E. D. Wyant Vidicon photoconductors J. F. Heagy 22 The image isocon-an improved image orthicon E. M. Musselman, R. L. VanAsselt 24 Ceramic -metal tetrodes for distributed amplifier service C. E. Doner, W. R. Weyant 29 Klystron for the Stanford two-mile linear accelerator A. C. Grimm, F. G. Hammersand32 Environmental engineering laboratory J. M. Forman, J. B. Grosh36 Design of a 915 -MHz power triode for microwave cooking W. P. Bennett, D. R. Carter, I. E. Martin, F. W. Peterson, J. D. Stabley, D. R. Trout38 RCA Lancaster -25 years of engineering excellence 43 The heat pipe, an unusual thermal device R. A. Freggens, R. C. Turner 44 Ruggedization of camera tubes for space applications J. G. Ziedonis48 The Coaxitron J. A. Eshleman, B. B. Adams 52 Noble -gas -ion lasers R. J. Buzzard, J. A. Powell, J. T. Mark, H. E. Medsger 56 Design of cermolox tubes for single-sideband A. Bazarian 60 A sterilizable and ruggedized vidicon Dr. S. A. Ochs, F. D. Marschka64 Broadband, high -gain, L -band, power amplifier module R. L. Bailey, J. R. Jasinski68 Copyright 1969 RCA Corporation All Rights Reserved Milestones in color -picture- tube development H. R. Seelen Frequently a company, however heterogeneous its output, becomes identified in the mind of the public with a single, best-known product. The RCA Lancaster plant's life -span has encompassed many developments of high interest to scientists, engi- neers, the military services, and ordinary laymen. But of all the Lancaster products, the public is most aware of television picture tubes, and, in particular, color tubes. The 19 years during which Lancaster engineers have been engaged in developing and producing color tubes has been an eventful period. 'NROM THE BEGINNING,effort has to aid continued development of the r been applied principally to the RCA colorTVsystem as a whole, and shadow -mask type, which appeared to permit additional demonstrations of most suitable for development of the the system at various stages beginning several forms of color tubes investi- in the Spring of 1950. Ultimately, the gated by the RCA Laboratories. We system developed by RCA served as are often asked, today, why RCA has the "backbone" of the National Tele- adhered steadfastly over the years to vision Systems Committee recommen- this tube. The answer has good tech- dations, which were finally adopted nical and commercial foundations: no by the F.C.C. late in 1953. RCA thus other type has shown so desirable a became the major contributor to for- combination of good performance mulation of the present national stand- characteristics and mass -production ards for colorTVtransmission. suitability, brought about by a long series of engineering developments. Early color tubes Admittedly, the three -beam shadow - In addition to furnishing tubes for the Harry R. Seelen mask system is less efficient than other RCA color program, it was, of course, Division Vice President and General Manager systems as regards light output, and it an important part of Lancaster's as- Television Picture Tube Division has convergence complexities. But its Electronic Components signment to develop the color -tube received the BS in Physics from Providence Col- advantages are dominant: high con- design, with a view to eventual mass lege, and in June, 1968, Mr. Seelen received an trast and resolution, capabilities for production. The approach followed Honorary Doctor of Business Administration de- gree fromit.Mr. Seelen was appointed Division uniform color fields and high color during this early period beginning in Vice President and General Manager, Television saturation(whichisbuiltinto the 1949 was to explore the potentials of Picture Tube Division, of Electronic Components tube), fine dot -screen structure, and the flat -screen, flat -mask system. Be- on August 20, 1965. Previously, he had been Gen- eral Manager of the division since July 20, 1965. moderate circuit requirements, consid- cause accurate positioning of mask Mr. Seelen joined RCA in 1930 as a tube design ering both complexity and stability. apertures with respect to the phosphor - engineer at the Harrison, New Jersey, plant. Sub- screen dots(register) sequently he became Manager of the Tube Devel- Pioneering work in color Tv had been is extremely im- opment Shop.In 1942, he organized and set up done by RCA prior to World War II, portant, great emphasis was placed on the Engineering organization and laboratories at mounting arrangements for the thin, the new Lancaster plant. In 1943, with the transfer but the major advances in the com- of all non -receiving tube engineering to Lancaster, mercial program occurred after 1945. rather flexible, metal mask. In this con- he assumedchargeof EngineeringServices. An important milestone was passed in nection it was felt that tensioning the Seven years later, he was appointed Manager of all mask in a frame would provide great- Laboratory Engineering at Lancaster. In 1954, Mr. 1949 when field tests began and the Seelen became Manager of the Color Kinescope first demonstrations of the RCA com- est accuracy and stability of aperture Operations Departmentandlaterreturnedto patible system were held for the Fed- position. As a correlative advantage, a Harrison as Manager, Kinescope Operations.In flat screen opened up various possi- 1963, he was appointed Manager, Television Pic - eral Communications Commission. For tube Tube Operations Department ofthe RCA bilities for high-speed phosphor appli- Television Picture Tube Division, until his promo- this early work, the receivers used a separate picture tube for producing cation:initially, silk-screening; later, tion to General Manager of the division. He is a letter -press or offset methods.
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