IBM 1403

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The IBM 1403 line printer was introduced as part of the IBM 1401 computer in 1959 and had an especially long life in the IBM product line. The original model could print 600 lines of text per minute and could skip blank lines at up to 75 inches/second. The standard model had 120 print positions. An additional 12 positions were available as an option. A print chain with at least five copies of the character set spun horizontally in front of the ribbon and paper. Hammers struck the paper from behind at exactly the right moment to print a character as it went by. In later models, the print chain was replaced by a print train; print slugs instead of being mounted on a chain were placed in a track.

The standard 1403 chain or train could print 48 different characters: 26 letters, 10 digits, and 12 special characters: & , . - $ * / % # @ ≠ ⌑. Special chains or trains could be ordered for other character sets. Scientific users, for example, would use a chain that had the left parenthesis, the right parenthesis, and the plus sign in place of the per cent sign (%), the lozenge (⌑), and the ampersand (&). The numerics chain had more copies of fewer characters. (The "lozenge" is the square lozenge (U+2311) that resembles an overstuffed pillow, not the diamond-shaped one. Some Unicode typefaces do not render it correctly.)

The ink ribbon was a long roll the width of the print area that was positioned between the print chain and the paper. The roll came in two parts, the feeder roll and take-up roll. The roll was constantly wound and rewound during printing.

An IBM 1403, foreground, part of an IBM 7040 system used from 1964 to 1974 at the German university Technische Hochschule Darmstadt

Like most IBM printers of the era, the 1403 used fan-folded paper with perforated edges for tractor feeding. A carriage-control tape or, later, a buffer, under program control^[1], specified form length and the form line where printing was to begin so that paper of various sizes could be used.

An IBM 1403 printer played a cameo role in Stanley Kubrick's 1964 movie Doctor Strangelove, serving as a hiding place for a portable radio.

People with too much time on their hands were able to utilize the overstrike capability of the printer to generate a wide range of grey-scale equivalents. Many images were scanned, pixelated and could be reproduced on the 1403, most notably the Mona Lisa.^{[citation needed]}

These were huge and noisy machines, especially when the cover was raised. See the link below to learn how some people were able to use the timing of the print hammers to generate desired frequencies and actually play music.