13.11.2025 - IBM 3742 Datenerfassungsstation

IBM: The IBM 3742 Data Entry Station Punched cards, used since the 19th century as data storage media for statistical and commercial purposes, have several significant disadvantages in addition to various advantages such as decentralized data entry, readability for humans without technical aids, and sortability. To be processed by machines, very high-quality, expensive paper must be used that does not expand when humidity changes, and errors can generally only be corrected by re-punching. As an alternative to punched cards, IBM introduced the 8" floppy disk, and in 1974, as a counterpart to the card punch, the 3742 data entry station. With this system, data is written to 8" floppy disks, which, in the derived IBM 3742 format, with 77 tracks and 26 sectors, saw their first widespread use. Due to the extensive electronics required, the system was used for two data entry workstations. This is particularly evident in the station's screen: a single screen for two data entry operators, each displaying two lines of logical text! The two screen contents are mirrored to the two workstations. Initially, only 80-column data records could be entered, similar to punch cards. Only a paid add-on option allows full utilization of the 128 bytes of the floppy disk sectors. ~~~~~~~~~~~~~~~~~~~~ Presentation: Martin Kurtz, Klemens Krause Technical support: Ralph Braun, Christian Corti Camera and editing: Katja Stefanie Engstler Music: Ralph Braun ~~~~~~~~~~~~~~~~~~~~ #computermuseum #computermuseumstuttgart #ibm #ibm3741 #ibm3742 0:00 Introduction to 3742 18:52 Searching for a data record 23:54 Duplicating data 37:00 Checksums 38:30 Converting EBCDIC to ASCII