Title
NBS ammonia atomic clock
Alternative Title
The first atomic clock
Authors
NBS (Washington, D.C.)
Date of Issue
1948-08-12
Device Type
clock
Operating Principle
cell
Reference Species
ammonia
Quantum Transition
J=3, K=3
Reference Frequency
23 870 megacycles (23.870 GHz)
Output Frequency
50 Hz
1000 Hz
Fabrication Source
noncommercial
Host Institution
NBS (Washington, D.C.)
Status Timeline
Design: 1947–1948 (Forman 1985)
Operational: 1948-08-12 (Forman 1985)
Public demonstration: 1949-01-06 (Forman 1985)
Technical Design aspects: size, design etc.
See: Lyons 1949; Forman 1985.
Technical specifications: stability, precision
Stability of 1 part in 10 million, during a six-hour test run (Lyons 1949, 20).
Current Location
National Museum of American History, Smithsonian Institution
Product
lyons1949
forman1985b
Identifiers
https://libra.unine.ch/handle/20.500.14713/100455