Harold Black and his three-stage feedback amplifier
Abstract/Description: | Photo of Harold Black on the inset. Photograph of Black's three-stage feedback amplifier. Embodying the principle of negative feedback, these amplifiers were first used in 1936 as repeaters in the coaxial cables between the cities of New York, NY and Philadelphia, PA. Negative feedback made it possible for each amplifier to carry 780 telephone messages simultaneously with great clarity. |
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Subject(s): | Equipment and supplies Black, Harold S., 1898-1983 |
Date Created: | circa 1936 |
Credit Line: | Bell Laboratories / Alcatel-Lucent USA Inc., courtesy AIP Emilio Segrè Visual Archives, Lillian Hoddeson Collection. |
Catalog ID: | Black Harold F1 |
Title: | Harold Black and his three-stage feedback amplifier. |
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Type of Resource: | still image | |
Date Created: | circa 1936 | |
Extent: | 1 photographic print (black and white; 8 x 10 inches) | |
Abstract/Description: | Photo of Harold Black on the inset. Photograph of Black's three-stage feedback amplifier. Embodying the principle of negative feedback, these amplifiers were first used in 1936 as repeaters in the coaxial cables between the cities of New York, NY and Philadelphia, PA. Negative feedback made it possible for each amplifier to carry 780 telephone messages simultaneously with great clarity. | |
Identifier(s): | Black Harold F1 (Catalog ID) | |
Note(s): |
Credit Line: Bell Laboratories / Alcatel-Lucent USA Inc., courtesy AIP Emilio Segrè Visual Archives, Lillian Hoddeson Collection. |
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Subject(s): |
Equipment and supplies Black, Harold S., 1898-1983 |
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Held by: | Niels Bohr Library & Archives | |
Related Title: | Lillian Hoddeson Collection. | |
In Collections: |