Powers-Samas was a British company which sold unit record equipment.
In 1915 Powers Tabulating Machine Company established European operations through the Accounting and Tabulating Machine Company of Great Britain Limited, in 1929 renamed Powers-Samas Accounting Machine Limited (Samas, full name Societe Anonyme des Machines a Statistiques, had been the Power's sales agency in France, formed in 1922). The informal reference "Acc and Tab" would persist.
During the Second World War it produced large numbers of Typex cipher machines, derived from the German Enigma, for use by the British armed forces and other government departments. In 1959 it merged with the competing British Tabulating Machine Company (BTM) to form International Computers and Tabulators (ICT).
Powers-Samas equipment was entirely mechanical, unlike IBM equipment where rectangular holes in punched cards were converted into electrical signals as they passed under a row of wire brushes. Pins that could drop through round holes in cards were connected to linkages and their displacement when a hole was present actuated other parts of the mechanism to produce desired results.
Setting up a machine involved building a suitable network of linkages. According to one user, this "was achieved by locating above the reading block, in contact with the tops of the matrix pins, a removable Y-shaped 'connection box' (equivalent to the Hollerith plug board) which was hard-wired spcifically [sic] to the job. The box had at the base as many rods as were needed to read the positions within the used data fields, so that, when forced down, appropriate features of the machine - printheads, counters or control links were physically set as a reaction to the moving tops of the connecting box rods. Thus while many connection wires were straight-through, some sensed holes needed to allow multiple actuation, while some multiple code-punching needed to be combined to achieve a single purpose. Designing the system, including setting up the tabulator, was the sales engineers job, while soldering the 'conn-box' forest of cranked rods to meet the design requirement was down to the skill of the Powers Engineer who was thus the doyen of the machine room."
While Powers-Samas used a variety of card sizes and formats, a 40-column card measuring 4.35 by 2 inches was common. There has been a 21 col. card as well as a 36 col. card with the necessary equipment of machines.
- Powers-Samas Card Punch, ComputerHistory.org, accessed September 2011
- Cortada p.57
- Pugh p.259
- Van Ness, Robert G. (1962). Principles of Punched Card Data Processing. The Business Press. p. 15.
- note from Dennis Hart at computermuseum.org.uk
- http://www.computerhistory.org/collections/accession/102722677 40-column card at Computer History Museum