Guide to the National Company (NATCO) Atomic Clocks Records
Digitized Content

Summary
Collection ID:
NMAH.AC.0547
Creators:
Bagnall, James
Orensberg, Arthur
NATCO, Inc. (National Company, Inc.)
Mainberger, Walter
Lerner, Louis C.
Holloway, Joseph
Grant, Eugene
George, James
Daly, Richard Timothy, Jr.
Bovarnick, Michael
Dates:
1955 - 1968
Languages:
English
Physical Description:
5.5 Cubic feet
16 boxes, 3 oversize folders
Repository:
The records document the development of the first commercial atomic clocks by the National Company, Inc., (NATCO) of Malden, Massachusetts, a company known for producing specialized electronic equipment. The records include blueprints, technical drawings and schematics, technical and research reports, instruction manuals, photographs, and marketing materials.

Scope and Contents
Scope and Contents
The National Company (NATCO) Atomic Clocks Records, 1955-1968, documents the development of the first commercial atomic clocks. Materials were generated by the National Company, Inc. (NATCO) of Malden, Massachusetts which produced the clocks under contract for military branches of the U.S. government and also marketed them on a retail basis. The collection consists of blueprints, technical drawings and schematics, technical and research reports, instruction manuals, photographs, marketing materials, and a stock offering prospectus for NATCO. If one blueprint, drawing or parts list had two or more models listed, it is included under the first model cited.
Series 1, National Company, Inc., (NATCO), 1957-1959, consists of a stock offering prospectus, 1959, which describes the organization of NATCO, its executives and Board of Directors, financial condition, and products. Located in this series is a bound volume of photographs which accompanied NATCO's contract bids. This volume contains photographs of a state-of-the-art machine shop and electronics laboratory of the late 1950s and early 1960s. A blueprint for a radio receiver— the product on which NATCO had built its reputation—is here.
Series 2, Atomichrons, 1955-1968, contains blueprints, original technical drawings and schematics, instruction manuals for setup and operation, technical and research reports, photographs and marketing materials arranged by Atomichron model from the National Atomic Frequency System (NAFS) prototype through the NC3701 and NC3702. The NC1001, the first commercial atomic clock, is fully documented. Technical Memoranda and proposals (TM-) related to particular models have been included with them. Other Technical Memoranda and proposals are in Series 3, Components, 1955-1957, and Series 5, Technical Memoranda and Reports, 1956-1957.
Series 3, Components, 1955-1967, contains materials related to the development of NATCo's Cesium Beam Tube and other parts of the Atomichrons. It includes Technical Memoranda (TM-), blueprints and original drawings, original notes and computations, parts lists, and photographs. Also included in this series is material related to the Production Engineering Measure (PEM), 1962-1967. This was a piece of equipment designed and built by NATCO to measure the accuracy of each Cesium Beam Tube as it was produced.
Series 4, Collision Avoidance System, 1962-1967, consists of material related to James J. Bagnall's patented Collision Avoidance System, using the Cesium Beam Frequency Standard. It includes his research report, the patent assigned to NATCO, and proposals and reports from NATCO representatives to Air Transportation Association conferences and meetings for 1967.
Series 5, Technical Memoranda and Reports, 1956-1967, consists of bound and numbered (TM-) technical memoranda. These are research reports and proposals for future research or products. Other technical memoranda are in Series 2, Atomichrons and Series 3, Components, 1955-1967.
Series 6, Reprints from Massachusetts Institute of Technology (MIT), 1953-1955, contains a bound volume of reprinted or photocopied papers which document research developments in Cesium Beam Frequency Standards at the time NATCO was establishing itself as a commercial producer.

Arrangement
Arrangement
The collection is arranged into six series.
Series 1: National Company, Inc., (NATCO), 1957-1959
Series 2: Atomichrons, 1955-1968
Subseries 2.1, National Atomic Frequency System (NAF), 1956
Subseries 2.2, NC1001, 1955-circa 1959
Subseries 2.3, NC1001, Polaris, 1956-1958
Subseries 2.4, NC2001, Militarized, 1956-1961
Subseries 2.5, NC3001, Airborne, 1956-1961
Subseries 2.6, NC1200, 1959
Subseries 2.7, Missileborne Atomichron, 1959-1960
Subseries 2,8, NC1501, 1958-1964
Subseries 2.9, NC1601, Economy, 1958-1964
Subseries 2.10, Tactical Frequency Standard Drawings, 1959
Subseries 2.11, Tri-Service CBFS, circa 1965
Subseries 2.12, NC3501, circa 1965, 1967
Subseries 2.13, NC3601, Aerospace, circa 1965
Subseries 2.14, NC3701, Commercial, 1964-1968
Series 3: Components, 1955-1967
Series 4: Collision Avoidance System, 1962-1967
Series 5: Technical Memoranda and Reports, 1956-1967
Series 6: Reprints from MIT, 1953-1955

Biographical / Historical
Biographical / Historical
An atomic clock is a cesium-based frequency standard. It operates by exposing cesium atoms to microwaves at one end of their resonant frequencies and then counting their corresponding cycles as a measure of time. In 1955, Louis Essen of Britain's National Physical Laboratory and William Markowitz of the U.S. Naval Observatory collaborated to produce the first measurement of what is now called the atomic second. In 1967, the 13th general Conference of Weights and Measures formally redefined the atomic second as 9,192,631,770. The atomic second became the internationally accepted unit of time. Atomic clocks are the most accurate of all clocks. The first clock in 1949 was based on the microwave resonances of the ammonia molecule. It was patented by Harold Lyons and Benjamin F. Husten. The first commercial atomic clocks were developed at the Massachusetts Institute of Technology (MIT) Research Laboratory of Electronics under J.R. Zacharias, a protégé of I.I. Rabi's, circa 1955-1956 and were manufactured by the National Company, Inc. (NATCO) of Malden, Massachussets. NATCO, founded in 1914, was a well-respected company known for producing specialized electronic equipment in short runs. Prototype clocks bore the working name National Atomic Frequency Standard (NAFS). When the first commercial product was unveiled on October 3, 1956, it bore the trade name "Atomichron" and the model number NC-1001. Between 1956 and 1960, fifty Atomichrons were made and sold to military agencies, government agencies, and universities. Nine other models followed with refinements in size, portability and accuracy. The most radical design departure began with the NC3001 when the beam tube was placed in the horizontal position. Prices ranged from $10,000 to $50,000.
Patents covering NATCO's frequency standards include: 2,960,663, 2,972,115, 2,991,389, 3,258,713, 3,305,290. In 1965, James J. Bagnall was assigned patent 3,167,772 for a Collision Avoidance System to NATCO. It never reached production.
Although supported by research contracts by all three military branches, especially the Army Signal Corps, NATCO failed to achieve a lasting profitability. It was liquidated, and its patents were acquired by Frequency Electronics in 1969.
Sources
1. PEM Drawing C43767, 1967, PEM Drawings (C38037-C43767), 1964-1967, Series 3, Components, 1955-1967, Atomic Clock Collection, Archives Center, Smithsonian Institution National Museum of American History.
2. Forman, Paul. "Atomichron: The Atomic Clock from Concept to Commercial Product," in Proceedings of the IEEE, vol. 73, p. 1181-1204, 1985.

Administration
Processing Information
Processed by Laura Zelasnic, August 1998; supervised by Alison Oswald, archivist.
Author
Laura Zelasnic.
Immediate Source of Acquisition
Materials in this collection were donated to the Division of Electricity and Modern Physics by Louis C. Lerner in December 1984. The bulk of the blueprints were purchased from Robert Reeves in August, 1991.

Using the Collection
Physical Characteristics and Technical Requirements
Gloves must be worn when handling unprotected photographs and negatives.
Conditions Governing Access
The collection is open for research use.
Preferred Citation
National Company (NATCO) Atomic Clocks Records, 1955-1968, Archives Center, National Museum of American History, Smithsonian Institution.
Conditions Governing Use
Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Other intellectual property rights may apply. Archives Center cost-recovery and use fees may apply when requesting reproductions.

Related Materials
Materials at the National Museum of American History
Artifacts related to this collection are located in the Division of Work and Industry.
Materials at Other Organizations
Materials related to MIT staff and departments who were involved in NATCO's Atomic Clock projects also can be found in the Historical Collections at the MIT Museum (http://web.mit.edu/museum/) and in the Institute Archives and Special Collections (http://libraries.mit.edu/archives/) of the MIT Libraries in Cambridge, Mass.

Accruals
Accruals
Additional materials were added to this collection in January 2012. The materials were collected by National Museum of American History Curator, Paul Forman, and were transferred to the Archives Center in 2012.

Custodial History
Custodial History
The collection was transferred from the Division of Electricity and Modern Physics (now the Division of Work and Industry) to the Archives Center in February, 1996.

Keywords
Keywords table of terms and types.
Keyword Terms Keyword Types
Blueprints -- 20th century Type Search Smithsonian Collections Search ArchiveGrid
Atomic clocks Topic Search Smithsonian Collections Search ArchiveGrid
Airplanes -- Collision avoidance -- 1950-1970 Topic Search Smithsonian Collections Search ArchiveGrid
United States -- Air defenses -- Military -- 1950-1970 Topic Search Smithsonian Collections Search ArchiveGrid
Inventions -- 1950-2000 Topic Search Smithsonian Collections Search ArchiveGrid
Frequency standards -- 1950-1970 Topic Search Smithsonian Collections Search ArchiveGrid
Cold War -- 1950-1970 Topic Search Smithsonian Collections Search ArchiveGrid
Clocks and watches -- 1950-1970 Topic Search Smithsonian Collections Search ArchiveGrid
Technical drawings Type Search Smithsonian Collections Search ArchiveGrid
Reports -- 1940-1970 Type Search Smithsonian Collections Search ArchiveGrid
Military-industrial complex -- Massachusetts -- Cambridge Topic Search Smithsonian Collections Search ArchiveGrid
Manuals -- 1950-1970 Type Search Smithsonian Collections Search ArchiveGrid
Photographs -- 1940-1970 Type Search Smithsonian Collections Search ArchiveGrid
Patents -- 1950-1970 Topic Search Smithsonian Collections Search ArchiveGrid

Repository Contact
Archives Center, National Museum of American History
P.O. Box 37012
Suite 1100, MRC 601
Washington, D.C. 20013-7012
archivescenter@si.edu
http://americanhistory.si.edu/archives