Difference between revisions of "RA70 disk drive"
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| − | + | {{Infobox Disk drive | |
| − | {{stub}} | + | | name = RA70 |
| + | | manufacturer = [[Digital Equipment Corporation|DEC]] | ||
| + | <!-- | year introduced = 198x --> | ||
| + | | controller = [[Standard Disk Interconnect#SDI Family of DSA Products|all SDI controllers]] | ||
| + | | capacity = 280 Mbytes (formatted)<br>350 Mbytes (unformatted) | ||
| + | | transfer rate = 1.4 Mbytes/sec | ||
| + | | average access time = 27 msec | ||
| + | | rpm = 4000 | ||
| + | | revolution time = 7.5 msec | ||
| + | <!-- | one track seek = x msec --> | ||
| + | | average seek = 19.5 msec | ||
| + | <!-- | maximum seek = x msec --> | ||
| + | | surfaces = 11 data, 1 servo | ||
| + | | number of heads = 11 data,<br>1 servo | ||
| + | | tracks = 1507 | ||
| + | | sectors = 34 | ||
| + | | bytes per sector = 512 | ||
| + | | tracks per inch = 1355 | ||
| + | | density = 22,437 | ||
| + | <!-- | recording method = [[Modified Frequency Modulation|MFM]] --> | ||
| + | | start time = 59 secs (avg) | ||
| + | | stop time = 15 secs (avg) | ||
| + | | physical size = 9cm x 14.6cm x 22.4cm | ||
| + | | weight = 10.5 lbs | ||
| + | | power consumption = 264 watts (idle) | ||
| + | }} | ||
| + | |||
| + | [[Image:ra70.jpg|thumb|left|200px|RA70]] | ||
| + | |||
| + | The '''RA70 disk drive''' is a [[Standard Disk Interconnect]] [[non-removable-media disk]] drive from [[Digital Equipment Corporation|DEC]]. Unlike all the other RA-series drives, it is a compact width - 5.25 inches wide. It has no internal [[power supply]]; it gets its power from the host system, or its SA7x enclosure. | ||
| + | |||
| + | Its capacity was 280 Mbytes (formatted). It was internally operated by a [[microprocessor]] which used 32-bit burst [[error-correcting code|ECC]] to invisibly repair simple data errors. | ||
| + | |||
| + | {{semi-stub}} | ||
| + | |||
| + | ==Further reading== | ||
| + | |||
| + | * ''RA70 Disk Drive Technical Description Manual'' (EK–ORA70–TD) - not available online | ||
| + | * ''RA7x Disk Drive Service Manual'' (EK–ORA7X-SM) - not available online | ||
| + | |||
| + | ==External links== | ||
| + | |||
| + | * [http://bitsavers.org/pdf/dec/brochures/DEC-RA-FamilyOfWinchesterDiskDrives.pdf RA Family Of Winchester Disk Drives] - brochure | ||
| + | <!-- * [http://bitsavers.org/pdf/dec/disc/ra70/ ra70] - documentation at [[Bitsavers]] --> | ||
| + | * [https://manx-docs.org/collections/mds-199909/cd3/disk/rsa7xpg2.pdf RA7x/SA7x Pocket Reference Guide] (EK–RSA7X–PG–002) | ||
| + | |||
| + | [[Category: SDI Disk Drives]] | ||
| + | [[Category: DEC Non-removable-media Disks]] | ||
Latest revision as of 00:15, 13 October 2024
| RA70 | |
| Manufacturer: | DEC |
|---|---|
| Drive Controller(s): | all SDI controllers |
| Capacity: | 280 Mbytes (formatted) 350 Mbytes (unformatted) |
| Transfer Rate: | 1.4 Mbytes/sec |
| Average Access Time: | 27 msec |
| Revolutions per Minute: | 4000 |
| 1/2 Revolution Time: | 7.5 msec |
| Average Seek Time: | 19.5 msec |
| Total Surfaces: | 11 data, 1 servo |
| Number of Heads: | 11 data, 1 servo |
| Tracks per Surface: | 1507 |
| Sectors per Track: | 34 |
| Bytes per Sector: | 512 |
| Tracks per Inch: | 1355 |
| Density: | 22,437 |
| Start Time: | 59 secs (avg) |
| Stop Time: | 15 secs (avg) |
| Physical Size: | 9cm x 14.6cm x 22.4cm |
| Weight: | 10.5 lbs |
| Power Consumption: | 264 watts (idle) |
The RA70 disk drive is a Standard Disk Interconnect non-removable-media disk drive from DEC. Unlike all the other RA-series drives, it is a compact width - 5.25 inches wide. It has no internal power supply; it gets its power from the host system, or its SA7x enclosure.
Its capacity was 280 Mbytes (formatted). It was internally operated by a microprocessor which used 32-bit burst ECC to invisibly repair simple data errors.
Further reading
- RA70 Disk Drive Technical Description Manual (EK–ORA70–TD) - not available online
- RA7x Disk Drive Service Manual (EK–ORA7X-SM) - not available online
External links
- RA Family Of Winchester Disk Drives - brochure
- RA7x/SA7x Pocket Reference Guide (EK–RSA7X–PG–002)
