punched paper tape
The punched tape is a storage medium that has been known since the middle of the last century and was still used for special applications until the 1980s. The punched tape existed in various designs, with the classic punched tape for the teleprinter having a width of 17.4 mm.
In addition to a Sprock row of holes for the feed, the perforated tape has up to 5 more rows of holes lying crosswise next to each other. The perforated strip is coded by means of punched holes according to the Baudot code or the teletype code. A total of 32 characters can be encoded with the 5- channel teletype punched strip. Since this is not sufficient for letters, numbers and special characters, a changeover signal, similar to a typewriter, was used to approximately double the number of combinations.
Besides the 5-channel punched tape, there are also the 6-, 7- and 8-channel punched tape. The latter has a width of 25.4 mm and was mainly used in computer technology from about 1950. Due to its low capacity and speed, it was soon replaced by magnetic tapes, magnetic drums and magnetic disks.