Editing Keypunch (section)

==Powers, Remington Rand (UNIVAC) keypunches==
Beginning around 1906, an employee of the [[United States Census Bureau]], James Powers, developed the ''Powers Keypunch'', which was specific to the census application and had 240 keys.<ref>Truesdell (1965) pp.119–126</ref><ref>Aspray (ed.) (1990) pp.124–125</ref>  In 1911, Powers formed [[Powers Accounting Machine Company]]. That company was taken over by [[Remington Rand]] in 1927.<ref>{{cite book |title= A History of Sperry Rand Corporation |publisher= Sperry Rand |year= 1967|version=4th printing}}</ref>  Remington Rand's [[UNIVAC]] division made keypunches for their 90-column cards and similar machines for the IBM 80-column card. Their 90-column keypunches used a mechanical system developed by Remington Rand to avoid IBM patent issues (long before the acquisition of [[Eckert–Mauchly Computer Corporation]]).  UNIVAC keypunches stored the sequence of characters for an entire card, then punched all its holes in a single pass, which allowed for corrections instead of wasting a card in case of error.

Remington Rand keypunches included: UNIVAC Card Code Punch Type 306-5, 90 Column Alphabetical (Types 306-2, 306-3), 90 Column Numerical (Types 204-2, 204-3), Portable Electric Punch Type 202,  Spot Punch Type 301, and the Automatic Verifying Machine Type 313.<ref>{{cite book | editor-last = Mecham| editor-first = Alan D. |title = Data Processing Equipment Encyclopedia Vol.1 Electromechanical Devices |publisher = Gillie Associates | year = 1961 }}</ref>

The Type 306-2 provided for verification; the cards were passed through the keypunch a second time  and keyed again. ''The verify-punching of the same cards in the same  sequence ... results in the elongation of perforations for correct information.  Round perforations indicate incorrect information. Complete and rapid detection of errors is performed mechanically by the Automatic Verifying Machine''<ref>Mecham (ed.) (1961) pp.197, 357</ref>

The UNIVAC 1710 Verifying Interpreting Punch was introduced in 1969.<ref>[http://www.technikum29.de/en/computer/punchcard UNIVAC 1710 keypunch]</ref>