Difference between revisions of "RA70 disk drive"

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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.  
 
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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==Further reading==
 
==Further reading==
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* [https://manx-docs.org/collections/mds-199909/cd3/disk/rsa7xpg2.pdf RA7x/SA7x Pocket Reference Guide] (EK–RSA7X–PG–002)
 
* [https://manx-docs.org/collections/mds-199909/cd3/disk/rsa7xpg2.pdf RA7x/SA7x Pocket Reference Guide] (EK–RSA7X–PG–002)
 
   
 
   
[[Category: MSCP Disk Drives]]
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[[Category: SDI Disk Drives]]
 
[[Category: DEC Non-removable-media Disks]]
 
[[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