Identifier: bellvol24telephonemag00amerrich ( find matches)
Title: Bell telephone magazine
Year: 1922 ( 1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: BayNet

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he extension of theuseful radio spectrum to wave lengthsat least as short as two or threemeters; advances in electronic and cir-cuit techniques to make possible gen-eration of extremely short pulses ofradio energy at high levels of power;and accurate measurement of timeintervals as short as a few hundred-millionths of a second. Making use of these new elementsof technology as well as of establishedcommunication and electronic art andscience, our Army and Navv labora-tories made remarkable progress dur-ing the 1930s in evolving researchmodels of object-location equipmentusing radio waves. Behind the cloakof secrecy essential to military re-search, they studied various radiomethods of object viewing, and se-lected the preferred system by themiddle of the 1930s. They thenworked intensely, within the limits oftheir resources, to improve and per-fect the system selected. The NavalResearch Laboratory pointed its ef-fort to equipments for use on ships. 1945-46 Radar and Bell Laboratories 225
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Radar development by Bell Laboratories was greatly facilitated by earlier experi-ence with such projects as measurement of the height of the ionosphere (left), andthe radio altimeter (right), both employing the echo technique while the Fort Monmouth SignalCorps Laboratory directed its atten-tion to equipments for army groundforces. On July 13, 1937, at the invitationof Commander (now Captain) W.G. Ruble, some Bell Laboratories en-gineers, accompanied by Commander(now Commodore) J. B. Dow, vis-ited the Naval Research Laboratoryat Anacostia, and were shown theradar work which was in progressthere under the immediate directionof Dr. A. H. Taylor. After thisvisit, as is Bell Laboratories practiceat the preliminary survey stage ofany new research program, an ana- lytical study and appraisal were made.A selected group of scientists andengineers made an analysis, as com-plete as was possible with availableinformation, of object locationthrough the use of radio wav^es. Thisincluded re-radiati

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