The IBM 3480 Magnetic Tape Subsystem has achieved significant improvements over its predecessor, the 3420, in speed, data density, and floor-space requirements. The 3-megabyte-per-second data rate of the 3480, which is 2.4 times that of the 3420, was accomplished through the use of chromium-dioxide tape stored in a compact, single-reel cartridge threaded to a take-up reel. A sixfold increase in data density over the 3420 allowed reduction of the size of the 3480 reel, which was essential for rapid acceleration of the tape in the 3480's reel-to-reel transport. The increased data density also demanded substantial improvements in tape guiding and tape-motion control. This paper describes how mechanical analysis and design contributed to the achievement of these advances and aided in overcoming the ensuing problems.
展开▼
