IBM 036
| Industry | Computer hardware |
|---|---|
| Founded | June 16, 1911 in Endicott, New York, United States |
Key people | Herman Hollerith (inventor of early keypunch devices), Raymond Loewy (industrial designer of IBM 024/026) |
| Products | Keypunch machines (IBM 024, IBM 026, IBM 029, IBM 056) |
| Website | www |
A keypunch is a machine designed to create holes in rigid paper cards at precise spots, determined by keys pressed by an operator. Comparable devices include the gang punch, pantograph punch, and stamp. The term also refers to equipment used for encoding data onto punched tape.
In the context of Jacquard looms, punched cards were assembled into paper chains that served as programs to control loom functions.[1]
For Hollerith machines and similar unit record apparatus, punched cards held information intended for processing. In computing systems utilizing punched card input/output, these cards contained either data or instructions directing machine operations.
Initial Hollerith keypunches operated manually; subsequent versions became electromechanical, integrating a keyboard with feeders for blank cards and collectors for the punched output. Some models printed characters corresponding to the punched holes at the top of each column. The discarded punched paper pieces, known as chad, were collected in a box often referred to at IBM as a chip box or bit bucket.
Verification of data frequently required re-entering information to compare against the punched cards, a process known as two pass verification. There was significant demand for keypunch operators, who were mostly women,[2] employed full-time within extensive keypunch departments responsible for data input tasks.
During the 1950s, Remington Rand launched the UNITYPER, which allowed direct data entry onto magnetic tape for use with UNIVAC systems. Later in 1965, Mohawk Data Sciences introduced an enhanced magnetic tape encoder as a partial substitute for keypunches. The emergence of microprocessors and affordable computer terminals led companies such as Inforex and Pertec to develop key-to-tape and key-to-disk solutions.[3]
Although keypunches and punched cards remained widespread through the 1970s, they were quickly supplanted by cost-effective CRT computer terminals. This transition eliminated the need for card-to-tape or card-to-disk transfers, reducing expenses and enhancing input accuracy. The introduction of video display terminals, interactive timeshared systems, and subsequently personal computers allowed original data creators to enter programs and information directly without intermediary keypunch operators.
Stamping Jacquard cards, 1801 through 1890
Initially, Jacquard cards were manually stamped or cut, sometimes utilizing guide templates. A later development involved sandwiching the card between two hinged perforated metal plates; punches were inserted according to the design before passing through a press. These manual techniques eventually gave way to mechanized methods. The so-called 'Piano machines,' named due to their keyboard-like keys and operation via keyboards, became predominant and operated similarly to unit record keypunch devices.
Hollerith and IBM keypunches, 1890 through 1930s
Herman Hollerith’s early device from the 1890s created round holes measuring 3/16 inch using standard ticket punches. These holes were positioned near card edges to facilitate punching. Hollerith later designed a more precise Keyboard Punch featuring a pantograph mechanism connecting a punch head to a pointer over a 12 by 20 grid, allowing operators to manually align punches.
In 1901, Hollerith patented a system where pressing one of twelve keys would punch a hole and automatically advance the card to the next column. This initial Type 001 keypunch used 45-column cards with round holes. In 1923, The Tabulating Machine Company released its first electric keypunch: the Type 011 Electric Keypunch, where each keystroke engaged a solenoid to punch holes. The widely adopted 80-column punched card format was introduced 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 enabled recording of alphabetic data on tabulating cards so that complete words and names could be printed along with 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 had separate alphabetical and numerical keyboards—the alphabetical resembling a manual typewriter but without shift, tab, backspace, or character keys; instead including skip, release, stacker, and '1' keys." – IBM Archives
Post-World War II IBM Keypunches and Verifiers for 80-Column Cards
The majority of IBM keypunches and verifiers utilized a shared electromechanical keyboard system to encode keystrokes. When a key was depressed, a series of bails activated to close electrical contacts that encoded the character. A feedback loop powered magnets which returned the keystem to its resting position, reset the encoding bails, and provided tactile and audible confirmation to the operator. Each machine developed its own unique tactile response influenced by wear and adjustments to contact points, although there was no direct mechanism for adjusting keyboard feel. Special function keys operated solely through electrical contacts without any mechanical encoding linkage.
Models such as the IBM 024, 026, and 029 keypunches accepted program cards that controlled functions like tabbing and automatic duplication of fields. The later IBM 129 model advanced this concept by employing electronic circuit cards allowing operators to write simple programs.
IBM 024 and 026 Card Punches
Released in 1949, the IBM 024 Card Punch and IBM 026 Printing Card Punch were nearly identical in design except for the addition of a printing mechanism in the 026. Both machines contained twelve precision punch units—one aligned with each card row—powered by robust actuators. Cards advanced one column at a time as punches created holes, producing a characteristic “chunk, chunk” sound during operation. These machines handled cards with 51, 60, 66, and 80 columns.
The IBM 026 had the capability to print characters above each punched column; by 1964, it was available in ten variants featuring different character sets. Scientific versions replaced four less commonly used commercial symbols with parentheses, an equal sign, and a plus sign.
The logic circuitry combined diodes, 25L6 vacuum tubes, and relay components. Vacuum tube circuits operated at approximately 150 VDC primarily for punch-clutch magnet control, while most other circuits ran at 48 VDC.
Printing was achieved through a 5 × 7 dot matrix wire array governed by a metal “code plate” containing up to 1,960 pins (35 pins × 56 characters). Pins corresponding to unprinted dots were machined away; pressing this plate against the wire array selectively engaged wires to imprint characters onto ribbon and card. This system presented maintenance challenges—wire breakage within narrow tubes was frequent and repairs were intricate. Additionally, non-standard punch patterns could damage the code-plate positioning mechanism even when printing was disabled because the mechanism remained coupled with the punch unit.
The external design of the IBM 024/026 Card Punches was crafted by industrial designer Raymond Loewy, renowned for his streamlined designs and railway cars from the 1930s–40s. The machines’ heavy steel frames with rounded edges embodied an industrial Art Deco aesthetic.
IBM 056 Card Verifier
The IBM 056 served as a verifier counterpart to the IBM 024 Card Punch and IBM 026 Printing Card Punch. It resembled the 026 keypunch mechanically and electrically but included a red error indicator lens on its cover. During verification, operators re-entered data which the machine compared against existing punched holes on the card. Verified cards were marked with a small notch along the right edge.
Most mechanical and electrical parts of the IBM 056 were shared with the IBM 024/026 models, except for its punch unit and print head. Instead of punches, it employed sensing pins to detect holes; any mismatch activated a contact bail that halted card advancement and lit an error light in red. The notching mechanism driven by solenoids was installed where the print assembly was located on the IBM 026.
Operators were allowed up to three attempts to correct errors during verification. If discrepancies persisted beyond three tries, an error notch was punched above the problematic card column and the “OK” punch function was disabled. Although both keypunch and verifier operators could make mistakes—meaning data might still be correct—multiple attempts helped reduce repeated errors. Some operators attempted to bypass this by guessing errors; consequently, certain machines restricted entries to a single attempt before error notching occurred.
Cards marked with error notches were generally re-punched using an IBM 024 or 026 by duplicating all correct columns up to the faulty one before manually entering corrected data. Duplication involved passing the card through sensing pins that transferred existing hole data onto a blank card; incorrect columns were then manually adjusted. The revised card underwent re-verification before receiving an “OK” mark.
Typewriter Card Punch Devices
The initial integration of a card punch with a typewriter, allowing specific text to be both typed and punched, was pioneered by Powers in 1925. The IBM 824 Typewriter Card Punch replaced the traditional 024 keyboard with an IBM electric typewriter, whereas the IBM 826 utilized the IBM 026 Keypunch keyboard.
IBM 029 Card Punch
Launched alongside the System/360 in 1964, the IBM 029 introduced new character codes for symbols such as parentheses, equal signs, and plus signs within the EBCDIC encoding system. While mechanically resembling the IBM 026, it featured a larger code plate containing 2240 printing-pin positions to accommodate EBCDIC’s expanded character set, enabling it to print punched characters directly onto the card.
The internal logic of the 029 initially relied on reed relays and diodes mounted on SMS cards, but later models transitioned to more durable wire contact relays. It operated using 48 volts DC power, eliminating the vacuum tubes found in earlier models like the 024 and 026. An optional "Left-Zero" function was available through four extra SMS cards, which automatically punched leading zeros for right-justified numeric fields, streamlining data entry tasks.
IBM 5924 Key Punch
Introduced as a T01 variant of the IBM 029 in IBM’s 1971 IBM Kanji System, the IBM 5924 Key Punch featured a unique keyboard design. Operators could use their left hand to access 15 shift keys while selecting from 240 Kanji characters with their right hand. This advancement facilitated processing of extensive East Asian character sets exceeding 10,000 symbols, meeting essential computing requirements for Chinese, Japanese, and Korean languages.
IBM 059 Card Verifier
The IBM 059 Verifier served as a companion device to the IBM 029 Card Punch but marked a significant departure from its predecessor, the IBM 056. It utilized optical sensing with a single light source distributed through fiber-optic lightpipes to detect card holes, resulting in much quieter operation compared to the mechanically noisy IBM 056. Despite this technological enhancement, its fundamental verification process remained unchanged.
Interestingly, some operators preferred the louder tactile feedback of the older IBM 056 and would press keys more forcefully on the quieter 059, sometimes leading to increased wear on the keyboard.
IBM 129 Card Data Recorder
Released with the System/370 in 1971, the IBM 129 was a transistorized keypunch capable of punching and verifying cards as well as functioning as an auxiliary online reader/punch unit for standard 80-column cards on compatible computers. A console switch allowed users to toggle between punch and verify modes.
Its standout feature compared to earlier keypunches was an electronic buffer that stored an entire card image for all 80 columns. This buffer enabled users to correct keystroke errors using the Backspace key before punching, eliminating the need to manually eject and replace cards after mistakes. Once ready, punching occurred automatically and at high speed upon pressing the Release key.
The logic circuitry was built using SLT modules mounted on a swing-out wire-wrapped backplane. The punching mechanism operated independently from typing speed, which improved overall throughput.
Up to six different programs could be selected via a rotary switch and stored in memory. Unlike previous models that used program drums, program cards were loaded through the card-feed path. The device also supported duplication by utilizing the stored card image and featured an integrated optical reader for card input.
Program card
The IBM 024, 026, and 029 keypunch machines, along with their verifiers (models 056 and 059), utilized Program Cards—also known as drum cards—to automate various tasks such as field skipping, default character insertion, and duplication. This system represented an advancement over the earlier Skip Bars by encoding control instructions on punched cards wrapped around a rotating drum, which were read by starwheels triggering electrical contacts.
Control information was encoded in the upper six rows [12,11,0,1,2,3], while an optional Second Program function employed the lower six rows [4,5,6,7,8,9]. Operators could select desired programs via a switch mechanism; the drums themselves were removable by disengaging a locking lever.
The program card dictated operational functions as outlined below:
| Function | #1 | Char. | #2 | Char. | Description |
|---|---|---|---|---|---|
| Field Definition | 12 | & | 4 | 4 | Punch every column except the first in a field |
| Initiate Automatic Skip | 11 | ||||
| 5 | 5 | Punch the first column of fields designated for skipping | |||
| Initiate Automatic Duplication | 0 | 0 | 6 | 6 | Punch the first column of fields set for duplication |
| Alphabetic Shift Mode | 1 | 1 | 7 | 7 | Switch keyboard to Alphabetic mode for a column |
| Leading Zero Print | 2 | 2 | 8 | 8 | Enforce printing of leading zeros or signs |
| Suppress Printing | 3 | 3 | 9 | 9 | Prevent printing in a given column |
Programming languages such as FORTRAN, RPG, and IBM’s Assembly language assigned specific columns for particular operations—for example, columns 1, 10, and 16. The program cards automated tabbing and field definitions in alignment with these conventions.
An illustrative example:
1.......10........20........30........40........50........60........70........80 1AAAAAAAA1AAAAA1AAAAAAAAAAAAAAAAAAA1AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA &&&&&&&&
In this layout, pressing skip after entering data advances the cursor to column 10; columns 72 through 80 might be configured to define numeric shift fields for special characters or sequence numbering.
It is important to note that "Field Definition" (code 12) and "Alphabetic Shift" (code 1) both print as A.
Use of program code 2 could produce invalid characters that might harm printers.
Program cards simplified operations such as gang punching—where constant fields are added across multiple decks—and could even be programmed to "play music" by rhythmically punching noisy characters.
IBM 5496 Data Recorder for 96 column cards
In 1969, IBM introduced the System/3 series of entry-level business computers featuring a novel smaller format: the 96-column punched card. To support this format, IBM developed the IBM 5496 Data Recorder—a keypunch device with integrated printing and verification capabilities—and the IBM 5486 Card Sorter specifically designed for these cards.
Powers, Remington Rand (UNIVAC) keypunches
Around 1906, James Powers at the United States Census Bureau invented the Powers Keypunch, designed expressly for census data entry. He established the Powers Accounting Machine Company in 1911; Remington Rand later acquired it in 1927.
Remington Rand’s UNIVAC division manufactured keypunches compatible with their own 90-column cards as well as machines supporting IBM’s standard 80-column cards. Their mechanical designs circumvented IBM patents. UNIVAC keypunches recorded an entire card’s data sequence before punching all holes in a single pass—allowing error correction prior to punching and minimizing waste.
Models produced by Remington Rand included: UNIVAC Card Code Punch Type 306-5 (90 Column Alphabetical Types 306-2 and 306-3), 90 Column Numerical (Types 204-2 and 204-3), Portable Electric Punch Type 202, Spot Punch Type 301, and Automatic Verifying Machine Type 313.
The Type 306-2 enabled verification through re-keying cards; correct entries resulted in elongated perforations while errors produced round holes that were mechanically detected by the Automatic Verifying Machine.
The UNIVAC 1710 Verifying Interpreting Punch was introduced in 1969.
Keypunch as a verb
The expression keypunched—originating from the now-defunct device—has come to signify data entry. This change mirrors the evolution from mechanical punched card input to contemporary digital data input techniques. Traditionally, "keypunching" consisted of pressing keys to print characters onto cards and create corresponding holes, which could then be read by a card reader.
Transition to direct data entry
During the 1950s, Remington Rand launched the UNITYPER, allowing data to be entered directly onto magnetic tape for UNIVAC machines. Subsequently, in 1965, Mohawk Data Sciences introduced an enhanced magnetic tape encoder designed as a keypunch substitute. The emergence of microprocessors and cost-effective computer terminals in the mid-1970s led smaller firms such as Inforex and Pertec to produce key-to-tape and key-to-disk solutions.
While punched cards remained widely used for data input and programming through the mid-1980s, removing the intermediate step of transferring data from cards to tape or disk lowered expenses and improved accuracy during entry. The introduction of video display terminals, interactive timeshared systems, and eventually personal computers empowered original data providers to input information directly, streamlining processes and lessening dependence on specialized data entry clerk personnel.
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)