Title
Oscillatom B 5000
Authors
Oscilloquartz
LSRH
Date of Issue
1966
Linked Datasets
Device Type
clock
Operating Principle
beam
Reference Species
cesium
Quantum Transition
hyperfine
Reference Frequency
9 192 631 770 Hz
Output Frequency
5 MHz, 1 MHz, 100 kHz
Fabrication Source
commercial
Status Timeline
Built: 1964 (Berger 1967)
Operational: 1966, first Oscillatom put into service at the ESRO satellite launching range in Kiruna, Sweden (Berger 1967)
Public demonstration: 1967, on the way to Montreal it was supposed to be displayed at the newly opened Swiss Center in New York and at the Smithsonian Institution in Washington, D.C. (Walthard 1967)
Exhibited: 1967-04-17–1967-10-29, Oscillatom exhibited in the time centre of the Swiss pavilion at the Montreal Universal Exhibition
Technical Design aspects: size, design etc.
The Oscillatom was constructed as a transportable rack-mounted system measuring 540 × 521 × 1,020 mm.
Initially, its atomic reference was a Varian BLR-2 cesium-beam tube.
The system employed two servo loops: the first locked the excitation-frequency chain to the cesium resonance, while the second controlled a 5 MHz quartz clock against the atomic reference. A numerical selector allowed different time scales to be produced, including atomic time and Universal Time. The quartz clock continued operating when the atomic-control loop was temporarily interrupted to inspect the cesium tube and its associated circuits.
Internal batteries provided approximately three hours of autonomous operation, extendable through external batteries.
Usage History
The first Oscillatom was built for ESRO’s satellite range at Kiruna, where it entered service in 1966. A second instrument formed part of the time centre in the Swiss horological pavilion at Expo 67 in Montreal.
Before its installation at the Montreal exhibition, the Oscillatom was scheduled to take part in a transported-clock comparison campaign in spring 1967. After being set to the time of the Neuchâtel Observatory, it would be compared with clocks and frequency standards at NASA’s Goddard Space Flight Center in Greenbelt, the U.S. Naval Observatory in Washington, D.C., and the National Research Council in Ottawa, to check synchronization between Swiss, American and Canadian time services (Kartaschoff 1966)
Current Location
MIH (B-5000 no. 14, 1969)
Product
berger1967
brandenberger1966
walthard1966
kartaschoff1966a
Identifiers
https://libra.unine.ch/handle/20.500.14713/100556