Cold War Atomic Bomb Testing – Time Conversion Computer

In October 18, 1947 the U.S. Secretary of Defence established Joint Task Force Seven for the purpose of readying the Eniwetok Atoll for use as a atomic bomb test site.  The task force included representatives from the Atomic Energy Commission, research establishments such as the Naval Research Laboratory and civilian companies; all under the control of the military.

The task force started work when a convoy of four ships sailed from Pearl Harbour. Eventually, some 9,800 people were to be involved in the project. A total of 50,000 tons of material were shipped to Eniwetok. One million feet of submarine cable was laid.

Forty three nuclear tests were conducted at Enewetak between 1948 and 1958. The first hydrogen bomb test, code-named Ivy Mike, was held in late 1952 as part of Operation Ivy, and it vaporized the islet of Elugelab.

Three weapons were detonated on Enewetak Atoll as part of Operation Sandstone in 1948.

Communications must always have been a problem. Multiple organisations were involved in locations which included Bikini, Eniwetok, Kwajalein, Hickam Field on Hawaii, Travis Air Force Base in California, Naval bases in Los Angeles and San Francisco, Washington  and Los Alamos.  Multiple time zones and an International Date Line complicated matters.

The Testing Time Conversion Computer  was used to calculate, convert and coordinate the specific timing of important events between  these locations.

It measures 4 5/8″ in diameter and is made of two white plastic disks held together by a metal grommet. One side performs time conversions, the other side has a map of some of the main locations and the distances between them.

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This is a very rare item.

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