IBM 826
| Industry | Computer hardware |
|---|---|
| Founded | June 16, 1911 in Endicott, New York, United States |
Key people | Herman Hollerith (inventor of early punched card devices), Raymond Loewy (industrial designer) |
| Products | Keypunch machines, punched card equipment |
| Website | www |
A keypunch is a mechanism designed to create holes in rigid paper cards at precise points determined by keys pressed by an operator. Comparable devices include the gang punch, pantograph punch, and stamp. The designation also extends to equipment that records information onto punched tape.
In the context of Jacquard looms, punched cards were linked together to form a "chain" that contained a program controlling the loom’s operations.
For Hollerith machines and similar unit record systems, punched cards stored data intended for processing. Within computer systems utilizing punched card input/output, these cards represented either data or software programs.
Initial Hollerith keypunches operated manually; subsequent versions were electromechanical devices resembling compact desks with typewriter-style keyboards, featuring hoppers for blank cards and stackers for those already punched. Certain models printed the character corresponding to the hole pattern at the top of each column. The removed card pieces dropped into a chad container, known at IBM as a chip box or bit bucket.
To ensure data accuracy, re-entry verification—known as two pass verification—was commonly performed. The profession of keypunch operator was in high demand, predominantly filled by women, who worked full-time in 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. By 1965, Mohawk Data Sciences developed an enhanced magnetic tape encoder marketed as a substitute for traditional keypunch machines. The emergence of microprocessors and affordable computer terminals brought about new key-to-tape and key-to-disk solutions from companies such as Inforex and Pertec.
Throughout the 1970s, keypunches and punched cards remained widely used but were swiftly supplanted by cost-effective CRT computer terminals. This transition eliminated the need to transfer data from punched cards to tape or disk, thereby reducing expenses and improving error detection during entry. The introduction of video display terminals, interactive timeshared systems, and eventually personal computers enabled originators to enter data and programs directly, removing reliance on keypunch operators.
Stamping Jacquard cards, 1801 through 1890
Jacquard cards were originally either stamped or cut manually, occasionally employing a guide plate. A later improvement involved placing the card between two hinged perforated metal plates, inserting punches according to the design, then pressing to create holes. These manual techniques were eventually replaced by mechanized processes. 'Piano machines,' named after their piano-like keys operated via keyboards, became predominant and functioned similarly to unit record keypunch devices.
Hollerith and IBM Keypunch Machines, 1890s to 1930s
During the early 1890s, Herman Hollerith developed a punched card device that utilized a ticket punch to create round holes near the edges for improved handling. He subsequently engineered a Keyboard Punch incorporating a pantograph mechanism that connected a punch tool to a guide pointer arranged over a 12 by 20 matrix, allowing manual alignment of punches.
In 1901, Hollerith secured a patent for a device where pressing any of the 12 keys would simultaneously punch a hole and advance the card automatically. This initial Type 001 keypunch featured 45 columns with round holes. Advancing technology, in 1923 The Tabulating Machine Company launched the Type 011 Electric Keypunch, which utilized solenoids activated by key presses to electrically punch holes. The 80-column punched card format made its debut in 1928.
Subsequent Hollerith keypunch models included the Type 016 Motor-Driven Electric Duplicating Keypunch (1929), the Type 31 Alphabetical Duplicating Punch (1933), and the Type 32 Alphabetical Printing Punch (1933).
"Alphabetical duplicating keypunches recorded alphabetic data on tabulating cards so that full words and names, alongside numeric information, could be printed later 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 alphabetical and numeric input; the alphabetical keyboard resembled a manual typewriter but omitted keys such as shift, tab, backspace, and character keys, instead including skip, release, stacker, and '1' keys." – IBM Archives
Post-World War II IBM Keypunches and Verifiers for 80-Column Cards
Most IBM keypunch and verifier keyboards employed a shared electro-mechanical system to encode keystrokes. Pressing a key activated a set of bails that closed electrical contacts to encode characters. A feedback loop energized magnets that returned the keystem to its resting position, reset the bails, and provided tactile as well as audible feedback. Each machine had its own distinctive "touch," influenced by factors such as wear, dirt accumulation, and contact spacing. The keyboards did not allow adjustment of this "feel" beyond minor contact tweaks. Special function keys were equipped solely with electrical contacts and lacked mechanical linkages.
Keypunch models such as the IBM 024, 026, and 029 accepted program cards which controlled features like tabbing and automatic duplication of data fields. The later IBM 129 incorporated electronic circuit cards enabling simple operator-programmed instructions.
IBM 024 and 026 Card Punches
Released in 1949, the IBM 024 Card Punch and IBM 026 Printing Card Punch were virtually identical except that the latter included printing capabilities. Both machines contained twelve high-powered punches—one per card row—that punched holes column-by-column with a characteristic sound. They supported processing of cards with 51, 60, 66, and 80 columns.
The IBM 026 printed characters corresponding to punched data above each column. By 1964, ten variants existed featuring different character sets; versions tailored for scientific use replaced seldom-used commercial characters with parentheses, equal signs, and plus signs.
The logic circuitry combined diodes, 25L6 vacuum tubes, and relays. Vacuum tubes operated at approximately 150VDC mainly powering punch-clutch magnets; most other circuits ran on a separate 48VDC supply.
Printing was accomplished through a 5×7 dot matrix wire array controlled by a metal "code plate" embedded with machined pins representing printable symbols. This plate pressed selected wires against an ink ribbon and card surface. The printing mechanism was notoriously difficult to service due to delicate wires housed within narrow tubes between the code plate and ribbon assembly. Use of non-standard "binary" punch patterns risked damaging the code plate’s positioning system by forcing it beyond its designed movement range; disabling printing stopped pin engagement but did not disengage the mechanism itself.
Renowned industrial designer Raymond Loewy, famous for his streamlined designs including railway cars from that era, crafted the award-winning external appearance of the robust steel IBM 024/026 Card Punches featuring rounded corners inspired by industrial Art Deco aesthetics.
IBM 056 Card Verifier
The IBM 056 served as the verification counterpart to the 024 Card Punch and 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 identical data keyed in by the original punch operator, with the machine confirming that the punched information matched. Cards that passed verification were marked with a small notch along the right edge.
Mechanically and electrically, the IBM 056 shared most components with the 024 and 026 keypunches, except for its punch unit and printing mechanism. Instead of punches, its unit contained sensing pins that detected existing holes; any discrepancies caused a contact bail to halt card feeding and illuminated a red error light. The notching system, powered by solenoids, took the place of the 026’s print head assembly.
If verification errors were found, operators had up to three chances to correctly re-enter data. After three unsuccessful attempts, an error notch was punched over the affected column, and the "OK" notch function was disabled. Although this method reduced mistakes, some operators could infer original errors by trial and error, leading certain machines to restrict verification to a single entry before applying an error notch.
Cards marked with error notches were corrected by re-punching on an 024 or 026 machine. This process involved duplicating columns up to the error point onto a blank card, then manually adjusting data before re-verification and final approval notching.
Typewriter Card Punches
The initial device combining card punching with typewriting capabilities—allowing selective typing and punching—was introduced by Powers in 1925. IBM’s 824 Typewriter Card Punch replaced the 024 keyboard with an IBM electric typewriter unit, while the IBM 826 merged an IBM 026 Keypunch with a typewriter interface.
IBM 029 Card Punch
Launched alongside System/360 in 1964, the IBM 029 introduced new character representations for symbols such as parentheses, equal signs, and plus signs within the EBCDIC character set. Its mechanical design closely resembled that of the IBM 026 but featured a larger code plate with 2240 printing-pin positions to support EBCDIC’s broader symbol range by printing punched characters atop cards.
The logic circuitry of later 029 models utilized wire contact relays; earlier versions employed reed relays combined with diodes on SMS cards. Due to reliability challenges with reed relays, IBM reverted to wire-contact relay technology. Operating at 48 volts DC, it eliminated vacuum tubes previously required in older units. An optional "Left-Zero" function enabled automatic insertion of leading zeros for right-justified numeric fields, streamlining data entry tasks.
IBM 5924 Key Punch
The IBM 5924 Key Punch represented a specialized variant of the Model T01 version of the 029, featuring a unique keyboard introduced during IBM’s 1971 announcement of the IBM Kanji System. This device allowed operators to input extensive character sets—exceeding 10,000 Kanji characters—by utilizing fifteen shift keys combined with up to 240 characters per shift position. This advancement facilitated computer processing for complex East Asian languages including Chinese, Japanese, and Korean.
IBM 059 Card Verifier
The IBM 059 functioned as the verification unit paired with the IBM 029 Card Punch. In contrast to the earlier mechanical-sensing IBM 056, the 059 utilized optical detection of card holes through fiber-optic lightpipes combined with a single light source, which greatly diminished operational noise. Despite this advancement in technology, the method of operation remained largely consistent with that of the 056.
Notably, some operators of the verifier missed the louder tactile feedback characteristic of the older model’s keystrokes when working alongside the quieter IBM 029 keypunch machines. This sometimes led them to press keys more forcefully, which in turn increased wear on the keyboard components.
IBM 129 Card Data Recorder
Launched alongside the System/370 in 1971, the IBM 129 integrated punching, verification, and supplementary online 80-column card reading and punching capabilities. A keyboard toggle switch allowed users to alternate between punch and verify modes.
The transistor-based IBM 129's primary innovation was its electronic buffer for all 80 columns, which enabled correction of typing errors using Backspace before any punching occurred. Earlier IBM keypunch models required removing and manually fixing cards after errors were detected. The entire card was punched automatically upon pressing the Release key.
Its logic circuits were implemented in SLT modules mounted on a swing-out wire-wrapped backplane. Unlike previous devices limited by column-by-column punching speed, the 129 was not constrained in this manner.
The machine could store up to six programs accessible via a rotary selector switch. Unlike predecessors that read program cards using a separate drum, programs were loaded into memory through the standard card path. Copying relied on these stored images, while an integrated optical reading unit allowed "read-in" functionality directly at the punch station.
Program card
Keypunch models such as IBM 024, 026, and 029, along with verifiers including the 056 and 059, employed Program Cards (also known as drum cards) to automate processes like field advancement, default character insertion, and duplication—enhancing earlier Skip Bar techniques.
A program card consisted of a punched card wrapped around a drum, encoding instructions via holes detected by starwheels that triggered electrical contacts. Programs were encoded in the upper six rows [12,11,0,1,2,3], with an optional secondary program available in the lower six rows [4-9], selectable by a switch. The drum was removable for replacement or reprogramming.
Functions programmed on these cards included field definition, automatic skipping or duplication of fields, alphabetic shifting, left zero printing, and print suppression:
| Function | #1 | Char. | #2 | Char. | Purpose |
|---|---|---|---|---|---|
| Field Definition | 12 | & | 4 | 4 | Punch every column except first within a field |
| Initiate Automatic Skip | 11 | - | 5 | 5 | Punch first column of fields designated to skip |
| Initiate Automatic Duplication | 0 | 0 | 6 | 6 | Punch first column of fields set for duplication |
| Alphabetic Shift | 1 | 1 | 7 | 7 | Switch keyboard to Alphabetic mode at specified column |
| Left Zero Print | 2 | 2 | 8 | 8 | Force printing of leading zeros or signs |
| Print Suppression | 3 | 3 | 9 | 9 | Suppress printing output in specified column |
Programming languages such as FORTRAN, RPG, and IBM Assembly language utilized particular card columns for their operations. Program cards could be configured to define these fields; for example:
1.......10........20........30........40........50........60........70........80 1AAAAAAAA1AAAAA1AAAAAAAAAAAAAAAAAAA1AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA &&&&&&&&
In this example, activating skip would advance from column 1 directly to column 10. Columns marked as "Numeric Shift" fields (for instance, columns 72 through 80) could contain continuation characters or sequence numbers.
It is important to note that "Field Definition" (12) and "Alphabetic Shift" (1) print as A. Program cards containing secondary program codes carried a risk of producing invalid characters that might damage printers.
Program cards facilitated automation tasks such as gang punching—applying constant data fields across multiple card decks—and could even be used creatively to generate rhythmic patterns by gang-punching noisy characters for entertainment purposes.
IBM 5496 Data Recorder for 96-Column Cards
In 1969, IBM introduced the System/3 series, a range of entry-level business computers that utilized a more compact 96-column punched card. The IBM 5496 Data Recorder, a keypunch device equipped with printing and verification capabilities, along with the IBM 5486 Card Sorter, were specifically engineered to handle these 96-column cards.
Powers and Remington Rand (UNIVAC) Keypunch Machines
Circa 1906, James Powers, working at the United States Census Bureau, developed the Powers Keypunch designed for census data input, featuring an extensive keyboard with 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, keypunch machines were manufactured for their own 90-column cards as well as compatible models for IBM’s 80-column format. Their mechanical design circumvented IBM’s patents by allowing the entire card’s data to be stored before punching all holes in one pass, facilitating error correction and minimizing card wastage.
Remington Rand’s product range included models such as the UNIVAC Card Code Punch Type 306-5 (covering 90 Column Alphabetical Types 306-2 and 306-3), 90 Column Numerical variants (Types 204-2 and 204-3), Portable Electric Punch Type 202, Spot Punch Type 301, and the Automatic Verifying Machine Type 313.
The Type 306-2 model offered verification by processing cards twice through the keypunch; accurate data entries produced elongated perforations while mistakes resulted in round holes. The Automatic Verifying Machine provided rapid mechanical error detection. Additionally, the UNIVAC 1710 Verifying Interpreting Punch was introduced in 1969.
Keypunch as a Verb
The expression keypunched—meaning to keypunch data—originated from operating keypunch machines but has since evolved to broadly signify data entry. Despite the physical keypunch devices becoming obsolete, this verb remains in use within business environments to describe inputting information into computer systems. Traditionally, keypunching involved pressing keys that simultaneously printed characters atop punched cards and created hole patterns readable by card readers.
Shift Toward Direct Data Entry
During the 1950s, Remington Rand launched the UNITYPER, an input apparatus enabling direct data recording onto magnetic tape for UNIVAC computers. Subsequently, Mohawk Data Sciences introduced an enhanced magnetic tape encoder in 1965 marketed as a replacement for conventional keypunch machines. By the mid-1970s, advances in microprocessors and affordable computer terminals led smaller companies like Inforex and Pertec to develop innovative key-to-tape and key-to-disk systems.
Although punched cards remained widely used for data input and programming through the mid-1980s, eliminating the intermediate step of transferring data from cards to tape or disk reduced expenses and improved error detection during entry. The emergence of video display terminals, interactive timeshared systems, and eventually personal computers allowed originators to enter data directly, bypassing traditional roles performed by 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)