BS ISO 4057:1986

Describes the characteristics of a 6,30 mm magnetic tape cartridge for data interchange and physical interchangeability between information processing systems utilizing the ISO 7-bit coded character set its extensions and/or the 8-bit coded character set. Covers references, definitions, environment and transportation, characteristics of the tape, characteristics of the cartridge, recording and format.

This International Standard specifies the characteristics of a 6.30 mm (0.25 in) magnetic tape cartridge intended for data interchange and physical interchangeability between information processing systems utilizing the ISO 7-bit coded character set (ISO 646), its extensions (ISO 2022) and/or the 8-bit coded character set (ISO 4873).

The cartridge is of the twin-hub coplanar type, loaded with a 6.30 mm (0.25 in) magnetic tape for digital recording using the 63 bpmm¹⁾ (1 600 bpi²⁾ phase-encoding method. The tape is transported between hubs by an internal belt capstan to the external drive. No tape driving or position sensing elements penetrate the cartridge. The direction of magnetization is in the longitudinal direction of the tape.

This International Standard applies to cartridges used for data interchange. Where it applies for testing only, this is specifically stated.

NOTE - Numeric values in the SI and/or Imperial measurement system in this International Standard may have been rounded and therefore are consistent with, but not exactly equal to, each other. Either system may be used, but the two should be neither intermixed nor reconverted. The original design was made using the Imperial measurement system.