Page:Open Skies (Kellermann).pdf/25

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K. I. KELLERMANN ET AL.

inaugurated a short wavelength circuit to provide a greater capacity. Although the Bell System transatlantic telephone calls were very expensive, they were subject to interference and fading and were not very reliable. Little was known at the time about short wave radio propagation or the limits to weak signal reception. Some noise originated in the receiver systems, but some was external. Some of the external static clearly came from passing automobiles and airplanes or from local thunderstorms, but some came from an unknown origin (Oswald 1930). According to Al Beck (1984), members of the Bell Labs radio research staff were aware that when connected to an antenna, the receiver noise was greater than when connected to a load, and that the level of noise depended on the antenna and the time of the day. So, it was understood that at least some of the noise was apparently external to the receiver system.

Still only 22 years old, on 20 July 1928, Karl Jansky reported for his first day of work at the AT&T Bell Telephone Laboratories, joining the tightly knit members of the Radio Research Division (Fig. 1.1). By August, after a two-­ week orientation class, Jansky was working at the Cliffwood Laboratory in New Jersey, little realizing that he was about to embark on an engineering

Fig. 1.1 Members of the Bell Labs Radio Research Division. Shown in the first row from left to right: Art Crawford, Carl Feldman, Sam Reed, Joe Johlfs, Lewis Lowery, Russell Ohl, Bill Mumford, Karl Jansky, Merlin Sharpless, Archie King, Edmund Bruce, and Al Beck. In the second row are Carl Englund, Harald Friis, Douglas Ring, Otto Larsen, Carl Clauson, Morris Morrell, Carl Peterson, Maurice Collins, Dan Schenk, and Jim Morrell. Credit: Courtesy of J.A. Tyson