IBM 129
| Industry | Computer hardware |
|---|---|
| Founded | 1911 |
| Headquarters | Armonk, New York , United States |
| Products | Keypunch machines, punched card equipment |
A keypunch refers to a mechanism designed to create holes in rigid paper cards at specific spots determined by keys pressed by an operator. Comparable devices include the gang punch, pantograph punch, and stamp. The designation also extends to machines that encode information onto punched tape.
In the context of Jacquard looms, punched cards were linked together forming a "chain" that contained a program to control the loom’s operation.[1]
For Hollerith machines and similar unit record devices, punched cards held data processed by these systems. When used in computers with punched card input/output, cards could represent either data or software instructions.
Early Hollerith keypunches operated manually; subsequent versions were electromechanical units resembling small desks equipped with typewriter-style keyboards, along with hoppers for blank cards and stackers for punched cards. Certain models also printed the character corresponding to each punched column above the holes. The discarded punched fragments, known as chad, were collected in a chad container or, at IBM, referred to as a chip box or bit bucket.
Many data processing workflows implemented two-pass verification, where data was entered twice to ensure correctness. This practice generated significant demand for keypunch operators, frequently women,[2] who were often employed full-time within large keypunch departments responsible for data entry tasks.
During the 1950s, Remington Rand introduced the UNITYPER, which allowed direct data input onto magnetic tape for UNIVAC machines. In 1965, Mohawk Data Sciences developed an enhanced magnetic tape encoder marketed as a substitute for traditional keypunches. The emergence of microprocessors and affordable terminals led smaller companies such as Inforex and Pertec to create key-to-tape and key-to-disk solutions.[3]
Although keypunches and punched cards remained widely used through the 1970s, they were swiftly supplanted by cost-effective CRT computer terminals. This shift eliminated the need for physical card transfer, reducing expenses and enhancing error correction during data entry. The introduction of video display terminals, interactive timeshared systems, and eventually personal computers enabled users to input data or programs directly rather than relying on keypunch operators.
Stamping Jacquard cards, 1801 through 1890
Initially, Jacquard cards were either stamped or manually cut, occasionally using a guide plate for precision. A later advancement involved positioning the card between two hinged perforated metal plates, inserting punches according to the design, then passing the assembly through a press to create the holes. These manual techniques were eventually replaced by keyboard-operated machines called 'Piano machines,' which functioned similarly to unit record keypunches.
Hollerith and IBM Keypunch Machines, 1890 to 1930s
During the early 1890s, Herman Hollerith created a device that utilized a standard ticket punch to produce circular holes near the edges of punched cards. He advanced this concept by inventing a more accurate Keyboard Punch, which incorporated a pantograph mechanism connecting a punching tool to a guiding pointer arranged over a 12 by 20 matrix, ensuring precise alignment of punches across 20 columns.
In 1901, Hollerith secured a patent for a system where operators would press one of twelve keys to punch holes, with the card automatically advancing after each punch. This initial Type 001 keypunch represented the first generation and employed 45-column cards with round holes. By 1923, The Tabulating Machine Company launched the first electrically powered keypunch, named the Type 011 Electric Keypunch. In this model, pressing a key closed an electrical contact that triggered a solenoid to create the hole. The 80-column punched card format was introduced five years later, in 1928.
Subsequent Hollerith keypunch models included the Type 016 Motor-Driven Electric Duplicating Keypunch (1929), followed by the Type 31 Alphabetical Duplicating Punch and Type 32 Alphabetical Printing Punch in 1933.
"Alphabetical duplicating keypunches captured alphabetic data on tabulating cards so that full words and names could be printed alongside numerical information by an alphabetical accounting machine. IBM introduced the Type 31 Alphabetical Duplicating Punch in 1933; it automatically ejected one card and fed another within 0.65 seconds. These machines featured separate keyboards for alphabetic and numeric input; the alphabetical keyboard resembled that of a manual typewriter but omitted keys such as shift, tab, backspace, and character keys, replacing them with skip, release, stacker, and '1' keys." – IBM Archives
Post-World War II IBM Keypunches and Verifiers for 80-Column Cards
Most IBM keypunches and verification machines employed a shared electromechanical keyboard design to encode keystrokes. When a key was pressed, it engaged a series of bails that closed electrical contacts to encode the character. A feedback mechanism activated magnets that mechanically returned the keystem to its resting position and reset the encoding bails, offering both tactile and audible feedback. Each unit developed its own distinctive "touch," influenced by wear patterns and contact adjustments; however, there were no options for customizing this feel beyond aligning contacts. Special function keys operated exclusively through electrical contacts without any mechanical linkage.
IBM models such as the 024, 026, and 029 supported program cards that controlled functions like tabbing and field duplication. The later-introduced Model 129 incorporated electronic circuit cards enabling operators to input simple programming instructions.
IBM Models 024 and 026 Card Punches
Introduced in 1949, the IBM 024 Card Punch and IBM 026 Printing Card Punch were largely similar except for the inclusion of a printing mechanism in the latter. Both machines contained twelve precision punches—one corresponding to each card row—that operated sequentially column-by-column to create holes in punched cards, producing their characteristic sound during operation. They were compatible with cards having 51, 60, 66, or 80 columns.
The IBM 026 featured a printing system that displayed punched characters above each column using a 5×7 dot matrix array controlled by a metal "code plate" embedded with machined pins representing various characters. By 1964, ten different versions existed featuring diverse character sets; scientific versions replaced some commercial symbols with mathematical ones such as parentheses and plus signs.
The underlying logic circuitry consisted of diodes, vacuum tubes (25L6), and relays. The tube circuits ran on approximately 150VDC primarily powering the punch-clutch magnet; most other circuits operated at around 48VDC.
This printing assembly was intricate and susceptible to damage—especially when duplicating "binary" cards containing irregular punch patterns—which could cause misalignment or breakage within components of the code plate mechanism. Even disabling printing did not eliminate mechanical stress since the code plate remained engaged during operation.
Renowned industrial designer Raymond Loewy applied his acclaimed streamlined aesthetic to these robust steel IBM punches. His design incorporated rounded corners reflecting industrial Art Deco influences while maintaining their heavy-duty construction.
IBM 056 Card Verifier
The IBM 056 functioned as a verification device designed to complement the 024 Card Punch and the 026 Printing Card Punch. Much like the 026 keypunch, it included a red error indicator lens on its casing. During operation, the verifier operator re-entered the data originally punched by the keypunch operator, allowing the machine to confirm accuracy. Cards that passed verification were marked with a small notch along the right edge.
Mechanically and electrically, the 056 was largely identical to the 024 and 026 models, with the primary differences found in its punch unit and print head components. Instead of punches, its punch unit was equipped with sensing pins that detected punched hole patterns. Any discrepancy between entered data halted card feed and activated a red error light. The mechanism responsible for notching, powered by solenoids, occupied the space where the 026’s printing mechanism was located.
Operators were permitted up to three attempts to correct errors during verification; if errors persisted beyond three tries, an error notch was punched above the problematic column, and the "OK" punch at the card’s end was disabled to prevent further processing. Although this system reduced repeated mistakes, some operators managed to guess errors correctly, prompting modifications that limited input to a single attempt before error notching occurred.
Cards marked with error notches were usually reprocessed on an 024 or 026 by duplicating verified columns and correcting erroneous ones before undergoing another verification cycle and receiving an "OK" notch. This duplication process involved reading existing holes through sensing pins and transferring data onto a blank card, applying corrections as necessary.
Typewriter Card Punches
The earliest device combining card punching with typewriter functionality for selective text entry was developed by Powers in 1925. IBM later introduced the 824 Typewriter Card Punch, which replaced the traditional 024 keyboard with an IBM electric typewriter. Similarly, IBM’s 826 model paired an electric typewriter with the IBM 026 Keypunch.
IBM 029 Card Punch
Launched alongside System/360 in 1964, the IBM 029 incorporated new character representations for symbols such as parentheses, equal signs, and plus signs within the EBCDIC encoding scheme. Though mechanically resembling the IBM 026, it featured a larger code plate accommodating 2240 printing-pin locations to handle EBCDIC’s expanded character repertoire, printing punched characters atop each card.
The control logic of early IBM 029 units employed reed relays combined with diodes mounted on SMS cards. Due to reliability concerns with reed relays, later models transitioned back to wire-contact relay technology. Powered by a 48-volt DC supply, it eliminated vacuum tubes previously required by earlier devices like the 024 and 026. An optional "Left-Zero" feature—implemented through additional SMS cards—enabled automatic insertion of leading zeros to right-justify numeric fields, streamlining data entry tasks.
IBM 5924 Key Punch
The IBM 5924 Key Punch was a specialized adaptation of the IBM 029 model T01 introduced in IBM’s 1971 IBM Kanji System. It featured a unique keyboard layout allowing operators to select one of fifteen shift keys using their left hand while choosing from among 240 Kanji characters with their right hand. This advancement facilitated computer processing for complex East Asian languages—including Chinese, Japanese, and Korean—each requiring extensive character sets surpassing ten thousand symbols.
IBM 059 Card Verifier
The IBM 059 functioned as the verification unit paired with the IBM 029 Card Punch, yet it differed considerably from its predecessor, the 056 verifier. Rather than relying on mechanical pins, it utilized optical detection to read card holes, which resulted in a much quieter operation. This optical system was powered by a single light source distributed through fiber-optic lightpipes. Despite this technological advancement, the fundamental verification method closely resembled that of the 056 model.
Interestingly, some users of the verifier missed the louder auditory feedback provided by the 056, especially when working alongside the quieter 029 keypunch machines. This absence of sound sometimes caused operators to press keys more forcefully, potentially accelerating wear on the keyboard.
IBM 129 Card Data Recorder
Launched alongside the System/370 in 1971, the IBM 129 was a transistor-based keypunch capable of punching, verifying, and functioning as an auxiliary online reader/punch for 80-column cards. The keyboard featured a switch to alternate between punch and verify modes.
A major innovation was its electronic buffer that stored an entire 80-column card image. Unlike previous IBM keypunches that required manual correction of keystroke mistakes, the 129 allowed users to erase errors using the Backspace key and re-enter data before automatically punching the full card upon pressing Release.
The device’s logic circuits were built with SLT modules mounted on a swing-out wire-wrapped backplane. Its input speed was not constrained by punching each column immediately at keystroke time.
Up to six programs could be saved in memory and selected via a rotary switch. Unlike earlier models where program cards were read using a drum mechanism, the 129 loaded programs through the standard card path.
Duplication was streamlined by using the stored image of the preceding card, removing the need for a separate reading station. Additionally, cards could be optically read through an integrated unit.
Program card
IBM keypunches such as the 024, 026, and 029 models—as well as verifiers like the 056 and 059—could be programmed using a Program Card or drum card. These cards automated various functions including field advancement, default characters, duplication, and more, representing an improvement over earlier Skip Bars.
The program card was created on a standard punched card wrapped around a rotating drum. Holes were detected by starwheels triggering electrical contacts that encoded programming instructions in rows [12,11,0,1,2,3]. An optional Second Program mode utilized rows [4,5,6,7,8,9], selectable by a switch. The drum could be detached easily via a locking lever for replacement.
Functions encoded by program cards included:
| Function | #1 | Char. | #2 | Char. | Description |
|---|---|---|---|---|---|
| Field Definition | 12 | & | 4 | 4 | Punch all columns except first in field |
| Start Automatic Skip | 11 | - | 5 | 5 | Punch first column to skip fields |
| Start Automatic Duplication | 0 | 0 | 6 | 6 | Punch first column to duplicate fields |
| Alphabetic Shift | 1 | 1 | 7 | 7 | Shift keyboard to Alphabetic mode for column |
| Left Zero Print | 2 | 2 | 8 | 8 | Force printing of leading zeros or signs |
| Print Suppression | 3 | 3 | 9 | 9 | Suppress printing in column |
Programming languages such as FORTRAN, RPG, and IBM Assembly language often used specific columns (e.g., columns 1,10,16) for particular functions. Program cards could be tailored accordingly to automate tabbing and field setup.
For instance:
1.......10........20........30........40........50........60........70........80 1AAAAAAAA1AAAAA1AAAAAAAAAAAAAAAAAAA1AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA &&&&&&&&
In this example, pressing skip after entering initial characters would tab directly to column 10. Fields defined by "Field Definition" (12) frequently marked numeric shift areas for special symbols or sequence numbers.
Note that "Field Definition" (12) and "Alphabetic Shift" (1) characters print as A. Improper use of program code 2 could generate invalid or harmful printer characters.
Program cards facilitated automated operations such as gang punching—entering constant data across multiple decks—and could even be arranged to produce musical rhythms by punching patterns of noisy characters.
IBM 5496 Data Recorder for 96-Column Cards
In 1969, IBM introduced the System/3 series of entry-level business computers that utilized a more compact 96-column punched card. Specifically designed for these cards were the IBM 5496 Data Recorder, a keypunch device equipped with print and verification capabilities, along with the IBM 5486 Card Sorter.
Powers and Remington Rand (UNIVAC) Keypunch Machines
Around 1906, James Powers, working at the United States Census Bureau, created the Powers Keypunch tailored for census data processing, featuring 240 keys. In 1911, Powers established the Powers Accounting Machine Company, which was later acquired by Remington Rand in 1927. Under Remington Rand’s UNIVAC division, keypunches were manufactured to handle their 90-column cards as well as compatible devices for IBM’s 80-column format. Their mechanical design successfully avoided infringing on IBM patents well before the acquisition of Eckert–Mauchly Computer Corporation. UNIVAC keypunches operated by capturing the entire character sequence of a card before punching holes in a single pass, allowing for error correction without wasting cards.
Remington Rand’s keypunch lineup included models such as the UNIVAC Card Code Punch Type 306-5 (covering 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 Automatic Verifying Machine Type 313.
The Type 306-2 model supported verification through re-keying cards to detect mistakes; correct entries produced elongated perforations while errors were marked by round holes. The Automatic Verifying Machine could mechanically identify discrepancies at high speed.
In 1969, the UNIVAC 1710 Verifying Interpreting Punch was launched.
To Keypunch as a Verb
The verb keypunched—derived from keypunch—initially described the process of inputting data onto punched cards using keypunch machines. Although these devices have become obsolete, the term endures in describing data entry activities. This linguistic shift mirrors the transition from mechanical punched card input to contemporary digital data capture methods.
Shift Toward Direct Data Entry
During the 1950s, Remington Rand developed the UNITYPER, an input device that allowed direct data entry onto magnetic tape for UNIVAC systems. Subsequently, in 1965, Mohawk Data Sciences introduced an enhanced magnetic tape encoder marketed as a substitute for traditional keypunch machines. The mid-1970s witnessed the rise of microprocessors and affordable terminals facilitating key-to-tape and key-to-disk solutions from manufacturers like Inforex and Pertec.
Although punched cards remained prevalent for data entry and programming until the mid-1980s, eliminating the intermediate step of transferring data from punched cards to tape or disk lowered costs and improved accuracy during input. The advent of video display terminals, interactive timeshared systems, and eventually personal computers empowered users to enter data directly at its source, streamlining operations and reducing dependency on dedicated data entry clerks.
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)
Further reading
External links
- Columbia University Computing History: IBM Keypunch Devices
- IBM Archives: IBM 029 — Card Punch Machine
- IBM Archives: Keypunch Operation in the Railroad Industry (001 Model)
- IBM Punched Card Accounting Machines from 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).