RL01/02 disk drive
From Computer History Wiki
RL01 | |
Manufacturer: | Digital Equipment Corporation |
---|---|
Drive Controller(s): | RL11 (UNIBUS) |
Capacity: | 5.2 Mbytes (formatted) |
Transfer Rate: | 512 Kbytes/sec 3.9 usec/word (peak) |
Average Access Time: | 67.5 msec |
Revolutions per Minute: | 2400 |
1/2 Revolution Time: | 12.5 msec |
One Track Seek Time: | 15 msec |
Average Seek Time: | 55 msec |
Maximum Seek Time: | 100 msec |
Total Surfaces: | 2 |
Tracks per Surface: | 256 |
Sectors per Track: | 40 |
Words per Sector: | 128 |
Tracks per Inch: | 125 |
Density: | 3725 bpi (maximum) |
Recording Method: | Modified Frequence Modulation (MFM) |
Physical Size: | 19" W x 10-1/2" H x 25" L |
Weight: | 55 pounds |
Power Consumption: | 160W (running); 550 VA (starting) |
The RL01 is a 5MiB, single platter, removable pack disk drive introduced in 1976 by Digital Equipment Corporation. It used an IBM 5440 type pack, as used on the IBM System/3.
To keep the heads properly aligned on the tracks, it used a servo system driven by servo data written on the pack (along with sector headers) at the factory; packs cannnot be low-level re-formatted in the field.
The QBUS controllers are the RLV11 and RLV12, the latter being the Q22 version.
The RL02 is a higher density version, with twice as many tracks.