Powers-Samas was a British company which sold unit record equipment. The company was in competition with the British Tabulating Machine Company (BTM), with which it eventually merged in 1959 to form International Computers and Tabulators (ICT). Powers-Samas was also known as "Acc and Tab" (Accounting and Tabulating).[1]
Unlike IBM equipment where rectangular holes in punched cards were converted into electrical signals as they passed under a row of wire brushes, Powers-Samas equipment was entirely mechanical. 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.
Programming 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 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 'programming' 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."[2]
While Powers-Samas used a variety of card sizes and formats, a 40-column card measuring 4.35 by 2 inches was common.[2][3] There has been a 21 col. card as well as a 36 col. card with the necessary equipment of machines.