IBM 028
| Industry | Data processing equipment |
|---|---|
| Founded | 1911 |
| Headquarters | Armonk, New York , United States |
| Products | Keypunch machines, punched card equipment |
A keypunch refers to a machine designed to create holes in rigid paper cards at positions determined by keys pressed by an operator. Comparable devices include the gang punch, pantograph punch, and stamp. The designation also extended to equipment that encoded information onto punched tape.
In the context of Jacquard looms, punched cards were linked together to form a "chain" that contained a program guiding the loom’s operation.[1]
For Hollerith machines and other unit record apparatus, punched cards held data that these machines processed. In computing systems utilizing punched card input/output, the cards represented either data or programs controlling the machine's functions.
Initial Hollerith keypunch models operated manually; subsequent versions were electromechanical devices resembling compact desks fitted with keyboards akin to typewriters, complete with hoppers for unpunched cards and stackers for completed ones. Certain models included printing capabilities that displayed the character corresponding to each punched column at the top. The discarded punched pieces collected in a chad box, or in IBM terminology, a chip box or bit bucket.
In numerous data processing scenarios, punched cards underwent verification by re-entering data to confirm accuracy (two pass verification). There was considerable employment demand for keypunch operators, predominantly women,[2] who often worked full-time within extensive keypunch departments responsible for data input.
During the 1950s, Remington Rand launched the UNITYPER, which allowed direct data input onto magnetic tape used by UNIVAC systems. By 1965, Mohawk Data Sciences introduced an enhanced magnetic tape encoder as an alternative to traditional keypunches. The emergence of microprocessors and cost-effective computer terminals motivated smaller companies such as Inforex and Pertec to create key-to-tape and key-to-disk solutions.[3]
Throughout the 1970s, keypunches and punched cards continued to be widely used for entering data and programs but were swiftly supplanted by affordable CRT computer terminals. Removing the step of transferring card data to tape or disk lowered expenses and enhanced error detection during entry. The introduction of video display terminals, interactive timeshared systems, and eventually personal computers facilitated direct data and program input by users themselves rather than relying on keypunch operators.
Stamping Jacquard cards, 1801 through 1890
Jacquard cards were originally created by hand stamping or cutting, occasionally utilizing a guide template. A refinement involved sandwiching the card between two perforated metal plates, inserting punches based on the desired pattern, then passing this assembly through a press to perforate the card. These manual techniques were eventually replaced by keyboard-operated machines known as 'piano machines,' which functioned similarly to unit record keypunch devices.
Hollerith and IBM Keypunch Machines, 1890s to 1930s
During the early 1890s, Herman Hollerith developed a device that punched circular holes measuring 3/16 inch in diameter. These holes were positioned close to the edges of the cards to facilitate easier punching. Subsequently, Hollerith advanced this technology by introducing a more accurate Keyboard Punch employing a pantograph system, which enabled operators to manually punch holes aligned within a 12 by 20 grid.
In 1901, Hollerith secured a patent for a keypunch machine where an operator pressed one of twelve keys to create a hole, with the card automatically advancing after each punch. This Type 001 keypunch utilized 45-column cards with round holes. The Tabulating Machine Company later launched the first electrically powered keypunch in 1923, named the Type 011 Electric Keypunch, which used electrical contacts and solenoids to perform punching operations. The 80-column punched card format was introduced in 1928. Subsequent models included the Type 016 Motor-Driven Electric Duplicating Keypunch (1929), Type 31 Alphabetical Duplicating Punch (1933), and Type 32 Alphabetical Printing Punch (1933).
Alphabetical duplicating keypunches captured alphabetic data on tabulating cards, enabling complete words and names alongside numerical entries to be printed subsequently by an alphabetical accounting machine. IBM introduced the Type 31 Alphabetical Duplicating Punch in 1933; it could automatically eject one card and feed another within 0.65 seconds. These devices featured separate keyboards for alphabetic and numeric input. The alphabetic keyboard resembled a manual typewriter but excluded shift, tab, backspace, and character keys while incorporating skip, release, stacker, and '1' keys. – IBM Archives
Post-World War II IBM Keypunches and Verifiers for 80-Column Cards
Most IBM keypunch machines and verifiers utilized a shared electromechanical keyboard design that encoded keystrokes through mechanical bails activating electrical contacts. Pressing a key triggered these bails to close circuits encoding characters. A feedback loop energized magnets that mechanically restored the keystroke position, reset encoding bails, and delivered both tactile and audible feedback. Each unit developed a distinctive "touch," influenced by wear and contact calibration; however, no direct tactile adjustments existed beyond contact tuning. Special function keys such as shift and duplication operated solely via electrical contacts without mechanical encoding components.
Models like the IBM 024, 026, and 029 keypunches accommodated program cards that controlled operations including tabbing and automatic field duplication. The later IBM 129 model incorporated electronic circuit cards allowing operators to input basic programmable instructions.
IBM 024 and 026 Card Punch Machines
Introduced in 1949, the IBM 024 Card Punch and IBM 026 Printing Card Punch were almost identical except that the latter included a printing feature. Both machines had twelve powerful punches—one assigned per card row—that activated sequentially column by column to produce holes in punch cards, generating a distinctive "chunk, chunk" noise during operation. They supported various card sizes including 51-, 60-, 66-, and 80-column formats.
The IBM 026 model printed characters above each punched column. By the year 1964, ten variants were available featuring different character sets; scientific versions replaced certain commercial symbols with parentheses, equal signs, and plus signs.
The internal logic was composed of diodes, 25L6 vacuum tubes, and relays. Vacuum tube circuits operated primarily at 150 VDC for controlling punch-clutch magnets, while most other circuits functioned at 48 VDC.
Character printing employed a 5 × 7 dot matrix wire assembly controlled by a metal "code plate" embedded with machined pins corresponding to printable characters. This plate pressed selected wires against an ink ribbon and card surface to form printed letters or symbols. The printing mechanism was delicate and difficult to maintain due to fragile wires housed within narrow tubes between the code plate and ribbon. Non-standard punch patterns could damage the code plate's positioning system by forcing it beyond its mechanical limits; disabling printing merely prevented pin pressing but did not disengage the mechanism.
Renowned industrial designer Raymond Loewy, celebrated for his streamlined aesthetics and railway car designs during the 1930s–40s, crafted the acclaimed external appearance of the IBM 024/026 Card Punches. Their sturdy steel framework with rounded edges embodied an industrial Art Deco influence.
IBM 056 Card Verifier
The IBM 056 functioned as the verification counterpart to both the 024 Card Punch and the 026 Printing Card Punch. Visually similar to the 026 keypunch, it was distinguished by a red error indicator lens on its cover. During operation, the verifier operator re-entered the same data keyed in by the original punch operator, allowing the machine to compare entries for accuracy. Cards that passed verification received a small notch along their right edge.
Mechanically and electrically, the IBM 056 shared most components with the 024/026 keypunch models, except that its punching mechanism was substituted with sensing pins designed to detect existing punched holes. When discrepancies occurred, card motion halted and a red error light was illuminated. The device’s notching assembly, positioned where the 026’s printing unit would normally be, utilized solenoids to create either a top-edge notch or an end-of-card notch.
Operators were permitted up to three attempts to rectify any detected errors during verification. If errors persisted after three tries, an error notch was punched above the faulty column at the top of the card, and the "OK" punch function was disabled. Although errors could originate from either operator involved, allowing multiple tries helped minimize repeated mistakes. Some operators attempted to bypass this by guessing corrections; consequently, modifications were introduced to limit re-entry attempts to only one before error notching was enforced.
Cards marked with error notches were typically re-punched—often by replicating data up to the error column using a 024 or 026 device—then corrected and subjected to re-verification before final acceptance.
Typewriter Card Punches
The earliest device combining card punching with typewriter capabilities, which allowed selective typing alongside punching, was created by Powers in 1925. IBM later introduced the 824 Typewriter Card Punch, replacing the 024’s keyboard with an IBM electric typewriter. The IBM 826 model incorporated an IBM 026 Keypunch keyboard, merging typewriter functionality with card punching to enhance data entry efficiency.
IBM 029 Card Punch
Launched alongside System/360 in 1964, the IBM 029 introduced new character codes—including parentheses, equal signs, plus signs, and other symbols—within the EBCDIC encoding scheme. Though mechanically akin to the IBM 026, it featured a larger code plate with 2240 printing-pin positions to support EBCDIC’s expanded character repertoire and printed punched characters atop cards.
The logic circuitry of later IBM 029 models employed wire contact relays; earlier versions utilized reed relays combined with diodes mounted on SMS cards. Due to reliability concerns with reed relays, IBM reverted back to wire-contact relay designs. Powered by 48 volts DC, it eliminated reliance on vacuum tubes found in predecessors such as the 024/026. An optional "Left-Zero" capability—implemented through four extra SMS cards—automatically punched leading zeros in numeric fields, thereby simplifying data entry and enhancing accuracy.
IBM 5924 Key Punch
The IBM 5924 Key Punch was a specialized variant of the IBM 029 model T01 developed for IBM's 1971 IBM Kanji System introduction. It allowed operators to enter complex East Asian scripts—including Chinese, Japanese, and Korean characters—by using one of fifteen shift keys with the left hand combined with selection among 240 Kanji characters using the right hand. This design facilitated processing of extensive character sets exceeding 10,000 symbols within computer systems.
IBM 059 Card Verifier
The IBM 059 functioned as the verification counterpart to the IBM 029 Card Punch. Unlike the earlier 056 verifier, it utilized optical detection of punched holes rather than mechanical pins, which greatly minimized operational noise. This model employed a single light source distributed through fiber-optic lightpipes, preserving similar verification capabilities while improving comfort for operators.
Despite these improvements, some users of the verifier missed the louder auditory signals produced by the 056. In environments where noisy IBM 029 keypunches were also in use, operators occasionally pressed keys more forcefully on the quieter 059, which sometimes led to accelerated wear on the keyboard mechanism.
IBM 129 Card Data Recorder
Launched alongside the System/370 in 1971, the IBM 129 integrated punching, verification, and online 80-column card reading and punching into one unit. A keyboard switch allowed users to toggle between punch and verify modes.
One of the transistorized IBM 129’s key innovations was its electronic buffer capable of storing an entire 80-column card image. Unlike previous IBM keypunch models that required ejecting and re-entering cards to correct keystroke mistakes, the 129 enabled users to erase errors using the Backspace key before automatically punching out the entire card upon pressing Release.
Its internal logic was built using SLT modules mounted on a swing-out backplane. The typing speed was not constrained by punching operations occurring simultaneously with keystroke entries.
The IBM 129 could hold six selectable programs via a rotary switch; unlike earlier machines that read program cards using a drum, this model loaded program cards into memory through the card-feed path. Duplication processes relied on stored images rather than separate read stations. An integrated optical reading unit allowed for "read-in" functionality directly through the punch station.
Program card
IBM keypunches such as the 024, 026, and 029 models, along with verifiers like the 056 and 059, could be programmed using a Program Card or drum card system. This innovation facilitated automatic field advancement, preset character types, duplication from prior cards, and other enhancements beyond earlier Skip Bar techniques.
The program card was punched with control codes and wrapped around a rotating drum; starwheels detected holes that activated electrical contacts encoding instructions within the top six rows [12,11,0,1,2,3]. An optional Second Program feature encoded additional commands in rows [4,5,6,7,8,9], selectable via a switch. The drum could be easily removed by tilting open the keypunch cover.
Functions provided by program cards included Field Definition (punching all but the first column), initiating Automatic Skip or Duplication at designated field start columns, Alphabetic Shift to change keyboard modes, Left Zero Print to enforce leading zeros or signs, and Print Suppression.
Many programming languages such as FORTRAN, RPG, and IBM Assembler designated specific columns on punched cards for coded instructions. Program cards automated repetitive tasks like gang punching constant fields or skipping to particular columns during data entry.
Example coding:
1.......10........20........30........40........50........60........70........80 1AAAAAAAA1AAAAA1AAAAAAAAAAAAAAAAAAA1AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA &&&&&&&&
In this example, pressing skip advances to column 10; columns 72-80 might define a Numeric Shift field used for special characters or sequence numbering.
Note: The "Field Definition" (12) and "Alphabetic Shift" (1) codes print as A. Incorrect application of program 2 codes could produce invalid characters potentially harmful to printers.
Program cards significantly boosted efficiency by automating repetitive data input and enabling complex functions such as gang punching or even generating rhythmic patterns for entertainment purposes.
IBM 5496 Data Recorder for 96-Column Cards
In 1969, IBM introduced the System/3 series of entry-level business computers, which utilized a novel, more compact 96-column punched card. The IBM 5496 Data Recorder—a keypunch device featuring printing and verification capabilities—alongside the IBM 5486 Card Sorter, were engineered specifically to handle these 96-column cards.
Powers and Remington Rand (UNIVAC) Keypunch Machines
Beginning around 1906, James Powers, working at the United States Census Bureau, developed the Powers Keypunch designed for census data collection with a keyboard of 240 keys. He established the Powers Accounting Machine Company in 1911, which was later acquired by Remington Rand in 1927. Under Remington Rand’s UNIVAC division, keypunch machines were manufactured for their proprietary 90-column cards as well as compatible models for IBM’s 80-column cards. These 90-column keypunches employed mechanical methods to avoid infringing on IBM patents. UNIVAC’s machines recorded all characters of a card before punching holes in a single operation, allowing corrections without wasting cards.
Remington Rand's range of keypunch devices included the UNIVAC Card Code Punch Type 306-5 (90 Column Alphabetical), Types 306-2 and 306-3 (90 Column Alphabetical), Types 204-2 and 204-3 (90 Column Numerical), Portable Electric Punch Type 202, Spot Punch Type 301, and Automatic Verifying Machine Type 313.
The Type 306-2 model enabled verification by running cards twice through the keypunch; accurate entries produced elongated holes while mistakes showed as circular perforations. The Automatic Verifying Machine was capable of swiftly identifying errors through mechanical means.
In 1969, the UNIVAC 1710 Verifying Interpreting Punch was introduced.
To Keypunch as a Verb
The verb keypunched originally described the process of encoding data onto punched cards using a keypunch machine. Although physical keypunch devices have become obsolete, the term has evolved to broadly signify data entry. This change mirrors the progression from mechanical input methods to contemporary digital data entry techniques.
Shift Toward Direct Data Input
During the 1950s, Remington Rand launched the UNITYPER, an input device that allowed direct data entry onto magnetic tape for use with UNIVAC systems. Subsequently, Mohawk Data Sciences introduced an enhanced magnetic tape encoder in 1965 that served as a substitute for traditional keypunches. By the mid-1970s, advancements such as microprocessors and affordable computer terminals led to the development of key-to-tape and key-to-disk solutions offered by companies like Inforex and Pertec.
Although punched cards continued to be widely used for data input and programming into the mid-1980s, removing the intermediate step of transferring data from punched cards to tape or disk lowered costs and improved error detection during entry. The introduction of video display terminals, interactive timeshared systems, and eventually personal computers empowered users to input data directly, simplifying workflows and decreasing dependency on specialized data entry clerk roles.
See also
- Punched card
- Punched card input/output
- Hollerith code
- Unit record equipment
- Computer programming in the punched card era
- List of IBM products
- Chad (paper)
Additional resources
External resources
- Columbia University Computing History: IBM Keypunch Devices
- IBM Archives: IBM 029 — Card Punch Machine
- IBM Archives: Railroad Applications (001 keypunch)
- IBM Punched Card Accounting Machines (1955)
- ↑ Bell, T.F. (1895) Jacquard Weaving and Designing, Longmans, Green And Co.
- ↑ IBM Archive: Keypunch operators, 1934, Stockholm
- ↑ Lua error in Module:Citation/CS1/Configuration at line 2123: attempt to index field '?' (a nil value).