Difference between revisions of "RA70 disk drive"

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[[Image:ra70.jpg|thumb|right|200px|RA70]]
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{{Infobox Disk drive
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280MB SDI HD with compact 5.25" size, 27 msec acces time, 1.4 BM/sec transfer rate
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| name = RA70
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| manufacturer = [[Digital Equipment Corporation|DEC]]
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<!-- | year introduced = 198x -->
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| controller = [[Standard Disk Interconnect#SDI Family of DSA Products|all SDI controllers]]
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| capacity = 280 Mbytes (formatted)<br>350 Mbytes (unformatted)
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| transfer rate = 1.4 Mbytes/sec
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| average access time = 27 msec
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| rpm = 4000
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| revolution time = 7.5 msec
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<!-- | one track seek = x msec -->
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| average seek = 19.5 msec
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<!-- | maximum seek = x msec -->
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| surfaces = 11 data, 1 servo
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| number of heads = 11 data,<br>1 servo
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| tracks = 1507
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| sectors = 34
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| bytes per sector = 512
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| tracks per inch = 1355
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| density = 22,437
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<!-- | recording method = [[Modified Frequency Modulation|MFM]] -->
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| start time = 59 secs (avg)
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| stop time = 15 secs (avg)
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| physical size = 9cm x 14.6cm x 22.4cm
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| weight = 10.5 lbs
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| power consumption = 264 watts (idle)
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}}
  
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[[Category:DEC Disk Drives]]
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[[Image:ra70.jpg|thumb|left|200px|RA70]]
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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.
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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.
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{{semi-stub}}
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==Further reading==
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* ''RA70 Disk Drive Technical Description Manual'' (EK–ORA70–TD) - not available online
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* ''RA7x Disk Drive Service Manual'' (EK–ORA7X-SM) - not available online
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==External links==
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* [http://bitsavers.org/pdf/dec/brochures/DEC-RA-FamilyOfWinchesterDiskDrives.pdf RA Family Of Winchester Disk Drives] - brochure
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<!-- * [http://bitsavers.org/pdf/dec/disc/ra70/ ra70] - documentation at [[Bitsavers]] -->
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* [https://manx-docs.org/collections/mds-199909/cd3/disk/rsa7xpg2.pdf RA7x/SA7x Pocket Reference Guide] (EK–RSA7X–PG–002)
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[[Category: SDI Disk Drives]]
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[[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)


RA70

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

Retrieved from "https://gunkies.org/w/index.php?title=RA70_disk_drive&oldid=35323"