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cesium beam atomic clock, electronic unit
cesium beam atomic clock, electronic unit

cesium beam atomic clock, electronic unit

Datecirca 1960
Inventory NumberRS1502a
ClassificationClock
Subject
    Maker National Company, Inc. 1914 - 1970s
    User Robert Vessot
    User Norman Foster Ramsey Jr. 1915 - 2011
    User Smithsonian Astrophysical Observatory founded 1890
    Associate Name Harvard College Observatory founded 1839
    Cultural Region
      Place of Origin
        Dimensions215 x 46 x 56 cm, 500 lb. (84 5/8 x 18 1/8 x 22 1/16 in., 226.8 kg)
        Material
          DescriptionTall blue metallic rack full of electronic modules. This clock is better known as Atomichron.
          In Collection(s)
          Signedon plate, stamped: MANUFACTURED BY NATIONAL CO. INC. / MALDEN, MASS.
          Curatorial RemarksFor a large collection of atomic clocks and a detailed history, see the following <a href="http://invention.smithsonian.org/Resources/fa_atomic-clock_index.aspx" target="_blank">website</a>.
          FunctionCalculating component of the cesium atomic clock, including most of the electronic units that constitute its operation. Main function is to measure the frequency of microwave emissions from the cesium beam and use this frequency to calculate units of time.

          For more information on cesium beam atomic clocks, see A Brief History of Atomic Clocks at the NIST website.
          ProvenanceFrom Dr. Robert Vessot's laboratory at the Center for Astrophysics, Harvard University.
          Historical AttributesStarting in the 1960s, Robert Vessot, at the Smithsonian Astrophysical Observatory, together with several colleagues including Norman Ramsey, the creator of the Maser, developed the atomic clock based on it. This is one of the atomic clocks that resulted from that process. For more details of this development and its use in the verification of Einstein's General Relativity Theory, see Published References.
          box of nine parts for cesium beam atomic clock
          box of nine parts for cesium beam atomic clock
          National Company, Inc.
          Date: circa 1960
          Object number: RS1502d
          box of nine parts for cesium beam atomic clock
          box of nine parts for cesium beam atomic clock
          National Company, Inc.
          Date: circa 1960
          Object number: RS1502d.1
          transistorized cesium beam atomic clock
          transistorized cesium beam atomic clock
          National Company, Inc.
          Date: 1970
          Object number: RS1502c
          cesium beam for cesium beam atomic clock
          cesium beam for cesium beam atomic clock
          National Company, Inc.
          Date: circa 1960
          Accessories: Screws.
          Object number: RS1502b
          H-10 atomic hydrogen maser, bottom half
          H-10 atomic hydrogen maser, bottom half
          Hewlett-Packard Company
          Date: circa 1965
          Accessories: cavity resonator (1990-7-0004b), name plate (1990-7-0004c)
          Object number: 1990-7-0004a.1
          label from H-10 atomic hydrogen maser
          label from H-10 atomic hydrogen maser
          Hewlett-Packard Company
          Date: circa 1965
          Accessories: cavity resonator (1990-7-0004b)
          Object number: 1990-7-004a.1
          H-10 atomic hydrogen maser, top half
          H-10 atomic hydrogen maser, top half
          Hewlett-Packard Company
          Date: circa 1965
          Accessories: cavity resonator (1990-7-0004b), name plate (1990-7-0004c)
          Object number: 1990-7-0004a.2
          H-10 atomic hydrogen maser
          H-10 atomic hydrogen maser
          Varian Associates
          Date: circa 1964
          Accessories: metal maker's name plate is on top of the other maser's cavity on B18-E5.
          Object number: 1998-1-1628
          "electric eye" slave clock
          "electric eye" slave clock
          George Washington Pierce
          Date: 1920-1928
          Accessories: Inside the clock: long pendulum staff; cylindrical brass weight; knob; an installation plan. in accessories box of master clock RS0116a: some of the suspension and electrical contacts are for the slave clock.
          Object number: RS0116b
          Image Not Available for three large copper templates
          three large copper templates
          Andreas Koehler
          Date: circa 1980
          Accessories: large copper template (3), large circuit board (3), black metal frame (3), metal connectors, Texas Nuclear booklet, catalog sheets from RIDL, a plastic 12-inch ruler
          Object number: 2003-1-0269b
          Image Not Available for three large circuit boards
          three large circuit boards
          Andreas Koehler
          Date: circa 1980
          Accessories: large copper template (3), large circuit board (3), black metal frame (3), metal connectors, Texas Nuclear booklet, catalog sheets from RIDL, a plastic 12-inch ruler
          Object number: 2003-1-0269c
          Image Not Available for two black metal frames
          two black metal frames
          Andreas Koehler
          Date: circa 1980
          Accessories: large copper template (3), large circuit board (3), black metal frame (3), metal connectors, Texas Nuclear booklet, catalog sheets from RIDL, a plastic 12-inch ruler
          Object number: 2003-1-0269d