File:Bell telephone magazine (1922) (14733600936).jpg

Identifier: belltelephonemag22amerrich (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: Internet Archive

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thin another year the tests hadbeen completed and the WesternElectric Company was providedwith the data necessary to beginproduction. Today, three yearslater, many of these instrumentsare in the hands of our armedforces. 26o Bell Telephone Magazine WINTER Thus the Murray Hill grounds be-came a typical anti-aircraft position.Four 90-mm. guns formed a quad-rangle. Dr. Harvey Fletcher, Di-rector of Physical Research, explainedto the audience that the guns areaimed and fired, either automaticallyor under control of the gunners, inaccordance with information calcu-lated and transmitted by the elec-trical director. ing hand-wheels or by setting anautomatic device that aids in thetracking. The man who follows theplane in azimuth—the horizontalangle—holds the vertical cross hairson the target. In doing this the en-tire tracker, including the men on theseats, is rotated to follow the move-ment of the hostile plane. Thesecond man elevates or depresses thetelescopes by holding the horizontal
Text Appearing After Image:
PRESS ASSOCIATION During the demonstration at Murray Hill, President Oliver E. Buckley of theLaboratories (left) and Major General L. H. Campbell, Chief of Ordnance, manipu-late the tracker as Dr. David B. Parkinson, originator of the concept, looks on How the Device Operates Sighting the target is done bymeans of a tracker. Two operatorspeer into telescopes, one on eitherside of the unit, and hold the crosshairs on the moving target by operat- cross hairs on the target—which maybe rapidly changing its elevation.He thus determines the elevationangle. These two angular positions,which fix the direction of the targetfrom the tracker, are automatically 1943-44 Electric Brain 261 and instantaneously converted intoelectrical terms by the device andtransmitted to the computer. In order to determine the exactposition of the plane in space, the and controls, considers the presentposition of the target as well as itsmovement; and from the changes inthe targets position, the computer de-termi

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