Identifier: belltelephonemag23amerrich (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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e va-garies of radio transmission. More-over, it was fairly obvious at the be-ginning, from a knowledge of theregion and the community of interestbetween the shores of the Bay, thata single voice channel would not ade-quately meet the demand for service.Several channels that could simultane- ZZ 34 Bell Telephone Magazi?7e SPRING ously carry telephone conversations strength of signals made possible would be needed—and of course this more practical and more powerful made the problem even more com- radio telephone transmitters. This plex. same kind of thing has taken place in Complex the problem was, in its many component parts and even in various aspects; but the answers were more complex systems and circuit ar- all found, and the system is working rangements, as the science of teleph- as the engineers planned. How the ony has made its great strides dur- problem was solved Is the subject- ing the past two decades or more, matter of the following pages. Radio telephone systems from the
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In this building at Cape Charles are installed both the radio equipment and theequipment to convert 12 wire telephone channels into the single radio channel An interplay between the alliedtelephone arts of transmission overwires and by radio has long beenfruitful of progress to both. As anexample, the vacuum tube, developedfirst as a radio detector, was improvedand modified to become the re-peater tube used in long wire cir-cuits. And then the ability of thisImproved vacuum tube to increase the first employed different frequencies,or bands, to separate individual sta-tions. One could tune In this sta-tion or that by adjustment of theradio receiving device. The radiotransmitters likewise were tuned tosend their signals on certain frequen-cies, much as one tunes the stringsof a musical instrument to sound cer-tain notes of tlie musical scale. This 1944 A Bridge for Speech Across Chesapeake Bay ZS radio technique of separating chan- and thus to transmit a number of nels for communication

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