IBM 3480 magnetic tape subsystem
- Model A22 Control Unit announced March 22, 1984
- Model B22 Magnetic Tape Unit announced March 22, 1984
- Models A11 and A12 Magnetic Tape Unit announced September 18, 1986
- Models A11 and B11 withdrawn December 19, 1989
The 3480 Magnetic Tape Subsystem was a major milestone in IBM storage. Two radically new features incorporated into its design were shape and size: square tape cartridges replaced the traditional round tape reels and the overall footprint of the box was reduced. In addition, data storage density and speed were improved.
Previously, the industry standard had been a 10.5-inch round tape reel that stored 160MB of data and had an uncompressed data rate of 1.25MB per second. The new 3480 used a 5.5-inch square cartridge, stored up to 200MB of data and executed at the rate of 3MB a second.
The 3480's rectangular cartridge compared to a standard tape reelAdditionally, the 3480 required less than half the floor space of an equivalent 3420 magnetic tape unit from just a decade earlier.
3480 technological breakthroughs
- First thin-film head in a tape drive.
- Several years ahead of introduction of thin-film heads in disk drives.
- First 18-track head/channel in a tape drive.
- First chromium dioxide media in the industry.
- Twice the data rate of competition.
- New media manufacturing process and patented formulation chemistry.
- Dramatically improved reliability and reduced maintenance costs.
- Significant function and complex system error logging enabled by major advancements in embedded software (microcode).
- Highest linear recording density of any storage device at the time.