Electromechanical Computer Component, ASSC Mark I

Electromechanical Computer Component, ASSC Mark I

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This is a component of the IBM Automatic Sequence Controlled Calculator (ASCC), known otherwise as the Harvard Mark I. The electromechanical assembly contains seven commutators, each with a plastic piece on top of it with a hole in it, with numbers stamped around the hole to denote contacts. It has a metal frame, gear, contacts, clutch and brushes.
Currently not on view
Object Name
Computer Component
Electromechanical Computer Component
Date made
Harvard University
place made
United States: Massachusetts, Cambridge, Harvard University
overall: 8 cm x 8 cm x 7.5 cm; 3 1/8 in x 3 1/8 in x 2 15/16 in
ID Number
accession number
catalog number
Credit Line
Gift of President and Fellows of Harvard University
See more items in
Medicine and Science: Mathematics
Computers & Business Machines
Data Source
National Museum of American History
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This is an electro-mechanical multiple output selector/sequencer relay. It is a similar variety to those formally used in analog telephone exchange line switching and in the Japenese PURPLE message encryption device.

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