The F6484, which began shipping in June 1999, was Fujitsu’s high-speed magnetic tape unit that used IBM 3590-format tape media. Fujitsu already had the F6470 magnetic tape unit (which started shipping in September 1987) that worked with IBM 3480-format tape media, the F6473A (which started shipping in March 1991), which could be expanded to house up to four drives, and the F6473K (which started shipping in July 1993), which recorded in a 36-track format. The F6484, however, dramatically increased the storage capacity per tape over 36-track magnetic tape units by recording in a 128-track format and, thus, met mounting needs for more data storage.
- The F6484 had the following features:
- （1）The 128-track magnetic head, which used thin-film technology, could record 86,360 bytes per inch, allowing up to 10 GB of data to be written to one tape
- （2）The F6484 recorded 128 tracks by making eight 16-track passes in a serpentine pattern
Note: The name serpentine came from the snake-like pattern that resulted from multi-pass tape recording - （3）The F6484 could transfer data at 13.5 megabytes per second
| F6484 magnetic tape unit |
(for reference) F6473K magnetic tape unit |
(for reference) F6473A magnetic tape unit |
|
|---|---|---|---|
| Initial shipping date | June 1999 | July 1993 | March 1991 |
| Tape media | Single-reel tape cartridges (width: 1/2nch, length: 2,070 feet) |
Single-reel tape cartridges (width: 1/2nch, length: 1,080 feet*1) |
Single-reel tape cartridges (width: 1/2 inch, length: 540 feet) |
| Cartridge dimensions [mm] | 110 x 128 x 26 (w x d x h) | 110 x 128 x 26 (w x d x h) | 110 x 128 x 26 (w x d x h) |
| Number of drive decks [decks/unit] | FACOM6484B4:4 FACOM6484B22:2 |
FACOM6473A4:4 FACOM6473A2:2 |
FACOM6473A4:4 FACOM6473A2:2 |
| Recording density [bytes/inch] | 86,360 | 75,742 | 37,871 |
| Recording tracks | 128 (eight-pass 16-track serpentine) | 36 (two-pass 18-track serpentine) | 18 |
| Recording format | RLL | GCR | GCR |
| Data transfer speed [MB/s] | 13.5 | 3.0 | 3.0 |
| Tape speed [inches/s] | 156 | 78.7 | 78.7 |
| Storage capacity [per cartridge] | 10 GB max.*2 (~20 GB with data compression) |
800 MB max.*2 (~2,400 MB with data compression) |
200 MB max.*3 (~400 MB with data compression) |
| Access time [ms] | 20 | 25 | 25 |
| Rewind time [s] | 55 | 40/80（*1） | 40 |
| Unload time [s] | 20 | 7/10*1 | 7 |
| Autoloader | Autoloader with 12-cartridge capacity | Autoloader with six-cartridge capacity | Autoloader with six-cartridge capacity |
*1. With double-length tape.
*2. When recording data in 32 Kbyte blocks with double-length tape.
*3. When recording data in 32 Kbyte blocks.
