IBM 002
| Industry | Computer hardware |
|---|---|
| Founded | June 16, 1911 |
| Founder | Charles Ranlett Flint (Tabulating Machine Company predecessor) |
| Headquarters | Armonk, New York , United States |
| Products | Keypunch machines, punched cards, data processing equipment |
| Website | www |
A keypunch refers to a machine designed to create holes in stiff paper cards at precise points determined by keys pressed by an operator. Comparable devices include gang punches, pantograph punches, and stamping tools. The term also encompasses equipment that transcribes information onto punched tape.
In the context of Jacquard looms, punched cards were linked together to form a "chain" that controlled the loom's functions.[1]
Within Hollerith machines and other unit record systems, punched cards stored data for processing purposes. When used as input/output media for computers, these cards represented either programs or data.
The earliest Hollerith keypunches operated manually; subsequent versions became electromechanical, resembling compact desks equipped with typewriter-style keyboards, input hoppers for blank cards, and output stackers for punched cards. Certain models also printed the character atop each column. The discarded punched fragments (chad) were collected in a chad box or, in IBM terminology, a chip box or bit bucket.
In numerous data processing environments, punched cards underwent verification by re-entering the data and comparing the results—a process known as two pass verification. There was considerable demand for keypunch operators, predominantly women,[2] employed full-time within extensive keypunch departments responsible for data input tasks.
During the 1950s, Remington Rand introduced the UNITYPER, which allowed direct data input onto magnetic tape for use with UNIVAC systems. In 1965, Mohawk Data Sciences advanced magnetic tape encoders marketed as alternatives to keypunch machines. The emergence of microprocessors and affordable terminals gave rise to key-to-tape and key-to-disk solutions from manufacturers such as Inforex and Pertec.[3]
Although keypunch devices and punched cards remained widely utilized through the 1970s, they were swiftly replaced by cost-effective CRT computer terminals. This transition eliminated the need for card transfers and enhanced error detection during data entry. The introduction of video display terminals, interactive timeshared systems, and eventually personal computers enabled originators to enter data or programs directly without relying on keypunch operators.
Stamping Jacquard cards, 1801 through 1890
Initially, Jacquard cards were manually stamped or cut by hand, occasionally guided by a template. A refinement involved sandwiching the card between two perforated metal plates, inserting punches according to the desired pattern, then passing the assembly through a press to create holes. These manual techniques were eventually supplanted by machinery. Commonly used were 'piano machines,' named after their keyboard-like keys; they operated similarly to unit record keypunches.
Hollerith and IBM keypunches, 1890 through 1930s
Herman Hollerith's initial card-punching apparatus from the 1890s utilized a standard ticket punch to create circular holes near the edges of cards. He later engineered a more accurate Keyboard Punch employing a pantograph system, which precisely positioned punches within a 12 by 20 grid for manual use.
In 1901, Hollerith secured a patent for a device where an operator pressed one of twelve keys to produce a hole, with the card automatically advancing to the next column. This inaugural Type 001 keypunch supported 45 columns and round holes. The Tabulating Machine Company introduced the first electric keypunch in 1923—the Type 011 Electric Keypunch—where each key press activated a solenoid to punch holes. The 80-column punched card format debuted in 1928. Subsequent Hollerith keypunch 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 information, to be printed by an alphabetical accounting machine. IBM introduced the Type 31 Alphabetical Duplicating Punch in 1933, which automatically ejected one card and fed another within 0.65 seconds. These devices featured separate keyboards for alphabetical and numerical input; the alphabetical keyboard resembled a manual typewriter but excluded shift, tab, backspace, and character keys while incorporating skip, release, stacker, and '1' keys.” – IBM Archives
IBM keypunches and verifiers for 80-column cards after World War II
The majority of IBM keypunches and verifiers employed an electromechanical keyboard design where keystrokes were encoded through mechanical bails that triggered electrical contacts. Each key actuation energized magnets responsible for mechanically returning the key to its original position and resetting encoding bails, thereby providing tactile feedback to the user. Differences in the "feel" of these keyboards resulted from wear and adjustments to contacts; however, no direct method existed for tuning this tactile response. Special function keys operated electrically without mechanical linkages.
Models such as the IBM 024, 026, and 029 allowed program cards to be mounted to automate tasks like tabbing and duplicating fields. The later IBM 129 incorporated electronic circuit cards enabling operators to write simple programs.
IBM 024 and 026 Card Punches
Launched in 1949, the IBM 024 Card Punch and IBM 026 Printing Card Punch were virtually identical except that the latter included a printing unit. Both machines contained twelve high-powered punches aligned with card rows, punching columns sequentially across multiple card formats including 51-, 60-, 66-, and 80-column cards. The characteristic “chunk, chunk” noise accompanied each column punch.
The IBM 026 printed characters corresponding to punched data above each column using a 5×7 dot matrix created by a metal "code plate" embedded with pins that selectively activated printing wires. Although innovative for its time, this printing mechanism was complex and susceptible to wire breakage or damage when duplicating non-standard "binary" cards, as forcing the code plate beyond its limits could cause malfunction.
Internally, logic circuits utilized diodes, vacuum tubes (specifically type 25L6), and relays powered mainly by 48V DC, with punch-clutch magnets operating at 150V DC.
Industrial designer Raymond Loewy was responsible for the acclaimed external styling of the IBM 024/026 punches, which featured robust steel construction with rounded edges embodying an industrial Art Deco aesthetic.
IBM 056 Card Verifier
The IBM 056 served as the verification counterpart to the 024 Card Punch and the 026 Printing Card Punch. Visually similar to the 026 keypunch, it was distinguished by a red error indicator on its cover. Verification operators duplicated the data entry performed by keypunch operators, with the verifier machine conducting a comparison to ensure punched information matched. Cards that passed verification were marked with a small notch along the right edge.
Most mechanical and electrical parts of the 056 were shared with the 024/026 units, except for its punch mechanism and print head. Instead of punches, its punch assembly contained sensing pins designed to detect existing holes; any mismatches halted card progression and illuminated a red error signal. The notching apparatus, which replaced the 026’s printing mechanism, utilized solenoids to select between placing a top notch or an end-of-card punch.
When verification errors were detected, operators had up to three chances to accurately re-enter data. If all three attempts failed, an error notch was punched over the problematic column, and the machine disabled the "OK" notch function. Although this procedure minimized repeated mistakes, some operators circumvented verification by guessing values, prompting modifications in certain machines to permit only one data entry attempt and apply error notching on a second try.
Cards flagged with error notches were generally re-punched using either an 024 or 026, copying data up to the error point before correcting it. This duplication process involved reading holes from the original card through sensing pins and transferring the data onto a blank card. The corrected cards then underwent re-verification to confirm accuracy and receive an "OK" notch.
Typewriter Card Punches
The initial integration of a card punch with a typewriter—allowing selective text to be both typed and punched—was introduced by Powers in 1925. IBM later released the 824 Typewriter Card Punch, which replaced the 024’s keyboard with an IBM electric typewriter. Likewise, the IBM 826 combined an IBM electric typewriter with an IBM 026 Keypunch.
IBM 029 Card Punch
Launched alongside System/360 in 1964, the IBM 029 supported new character symbols such as parentheses, equals, plus signs, and others within the EBCDIC character set. Mechanically akin to the IBM 026, it printed punched characters directly onto cards using an enlarged code plate featuring 2240 printing-pin positions to accommodate EBCDIC’s broader range of characters.
The logic circuitry of later 029 models employed wire contact relays, while earlier versions used reed relays paired with diodes on SMS cards. Due to reliability concerns associated with reed relays, IBM reverted back to wire-contact relay technology. Operating at 48 volts DC, the 029 eliminated the need for vacuum tubes found in prior models like the 024/026. An optional "Left-Zero" feature programmed via SMS cards enabled automatic punching of leading zeros, streamlining numeric data entry by right-aligning fields.
IBM 5924 Key Punch
The IBM 5924 Key Punch was a specialized version of the model T01 029 designed for IBM’s 1971 introduction of the IBM Kanji System. It featured a unique keyboard layout allowing operators to input complex Kanji characters—exceeding 10,000—in Chinese, Japanese, and Korean language scripts by combining fifteen shift keys with a selection of 240 characters. This innovation marked a significant advancement in processing extensive Asian character sets via computer systems.
IBM 059 Card Verifier
The IBM 059 functioned as the verification unit paired with the IBM 029 Card Punch. Unlike the earlier mechanical IBM 056 verifier, it utilized optical detection of card perforations through a single light source distributed by fiber-optic lightpipes, which greatly minimized operational noise. Despite this advancement in technology, its operational method closely resembled that of the 056.
Interestingly, some users preferred the louder feedback of the previous model and would press keys more forcefully on the quieter 059, sometimes leading to accelerated wear on the keyboard components.
IBM 129 Card Data Recorder
Launched alongside the System/370 in 1971, the IBM 129 integrated punching, verification, and an online 80-column card reading/punching capability tailored for specific computers. A keyboard toggle switch allowed users to alternate between punch and verify modes.
The transistor-based IBM 129's primary improvement over earlier IBM keypunch machines was its electronic buffer capable of storing an entire 80-column card image. Unlike previous models where correcting keystroke errors involved complex manual procedures, the 129 enabled users to erase mistakes using the Backspace key and re-enter data prior to automatic punching upon pressing Release.
Its circuitry employed SLT modules mounted on a swing-out, wire-wrapped backplane. The punching speed was no longer constrained by column-by-column processing. The 129 supported up to six stored programs selectable via a rotary switch; program cards were loaded into memory through the card-feed path rather than a dedicated program drum.
Thanks to its electronic memory, duplication was achieved by referencing the stored image of the preceding card instead of relying on a separate reading station. Additionally, cards could be optically read through a built-in unit located at the punch station.
Program Card
IBM keypunches such as the 024, 026, and 029 models, along with verifiers like the 056 and 059, utilized Program Cards (also known as drum cards) to automate functions including field advancement, default character types, and field duplication—offering enhancements over earlier "Skip Bars."
The program card was punched on any keypunch and wrapped around a rotating drum synchronized with card movement through the punch mechanism. Holes in the card were detected by starwheels activating electrical contacts. Programs were encoded within the top six rows [12,11,0,1,2,3]; an optional "Second Program" used rows [4-9] at the bottom and could be selected via a switch. The drum was removable for replacement using a locking lever.
Common program functions included:
| Function | #1 | Char. | #2 | Char. | Purpose |
|---|---|---|---|---|---|
| Field Definition | 12 | & | 4 | 4 | Punches every column except the first within a field |
| Start Automatic Skip | 11 | - | 5 | 5 | Punches first column of fields designated to skip |
| Start Automatic Duplication | 0 | 0 | 6 | 6 | Punches first column of fields set for duplication |
| Alphabetic Shift | 1 | 1 | 7 | 7 | Switches keyboard to Alphabetic mode in a column |
| Left Zero Print | 2 | 2 | 8 | 8 | Forces printing of leading zeros and signs |
| Print Suppression | 3 | 3 | 9 | 9 | Suppresses printing in a specific column |
Programming languages like FORTRAN, RPG, and IBM Assembly language assigned particular columns (such as 1,10,16,36,72) for coded instructions. An example program card configuration might specify numeric shift fields or continuation characters to facilitate efficient data entry.
It is noteworthy that "Field Definition" (12) and "Alphabetic Shift" (1) print as A. Utilizing program codes from set 2 could result in invalid characters or damage printers.
Program cards automated processes such as "gang punching," which involved inserting constant data fields across multiple cards in a deck. They also found creative applications like generating rhythmic patterns by alternating between noisy and quiet punched characters.
IBM 5496 Data Recorder for 96-Column Cards
In 1969, IBM introduced the System/3 lineup of entry-level business computers, which utilized a novel, more compact 96-column punched card format. To support these cards, IBM developed specialized equipment including the IBM 5496 Data Recorder—a keypunch machine featuring both printing and verification capabilities—and the IBM 5486 Card Sorter.
Powers and Remington Rand (UNIVAC) Keypunch Machines
Circa 1906, James Powers at the United States Census Bureau created the Powers Keypunch, designed specifically for census data with a keyboard comprising 240 keys. Powers established the Powers Accounting Machine Company in 1911, which was later acquired by Remington Rand in 1927. The UNIVAC branch of Remington Rand manufactured keypunch devices compatible with their 90-column punched cards as well as machines that could process IBM’s 80-column cards. To circumvent IBM’s patents, their 90-column keypunches utilized a mechanical approach distinct from IBM’s technology. These UNIVAC keypunches collected all card data before punching holes in a single operation, allowing users to correct errors without wasting cards.
Models produced by Remington Rand included: UNIVAC Card Code Punch Type 306-5 (with alphabetical versions 306-2 and 306-3), numerical models 204-2 and 204-3, Portable Electric Punch Type 202, Spot Punch Type 301, and Automatic Verifying Machine Type 313.
The Type 306-2 supported verification through a two-pass process where cards were run twice; accurate entries resulted in elongated perforations, while mistakes generated round holes. The Automatic Verifying Machine offered rapid mechanical error detection.
In 1969, the UNIVAC 1710 Verifying Interpreting Punch was released.
Keypunch as a Verb
The word keypunched—derived from the verb to keypunch—initially described the act of encoding data onto punched cards using a keypunch device. As physical keypunch machines became obsolete, this term evolved to broadly signify data entry itself. This linguistic shift mirrors the move from mechanical data input toward contemporary digital systems, where "keypunching" now generally refers to entering information directly into computers rather than onto punched cards.
Evolution Toward Direct Data Entry
During the 1950s, Remington Rand launched the UNITYPER, an input tool that allowed direct recording of data onto magnetic tape for use with UNIVAC computers. Subsequently, in 1965, Mohawk Data Sciences introduced an enhanced magnetic tape encoder marketed as a replacement for traditional keypunch machines. By the mid-1970s, advances in microprocessors and affordable computer terminals led firms such as Inforex and Pertec to develop key-to-tape and key-to-disk data entry solutions.
Although punched cards remained prevalent for programming and data input until the mid-1980s, bypassing the intermediate step of transferring data from cards to tape or disk reduced expenses and improved accuracy during entry. The rise of video display terminals, interactive timeshared systems, and eventually personal computers empowered users to input data directly at its source. This innovation streamlined workflows and diminished dependence 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)