1983 DEC RA60
Last disk pack disk drive
Last not Winchester technology i.e., relatively high mass and highly loaded head.

Why it’s important

Marks the end of an era that began with the 1301 (heads) and 1311 (removable disk packs).


It was an short 3330 style (SMD) 14" pack drive, with a unique embedded servo, and used a modified 3330 type head. It was a member of the Digital Storage Architecture (DSA) family, which included fixed block sizes, logical block addresses, automatic bad block revectoring, and Reed-Soloman ECC. The electrical interface was 4 pair serial radially connected to Unibus, BI Bus, and Cluster controllers (HSC series). A conventional moving voice coil linear motor was the actuator.

Bert Miller, a Mechanical Engineer, led the project.

According to Disk/Trend it was first shipped in1983 and is one of the last disk pack disk drive products to enter into new production.

The RA60 turned out to be a very reliable drive, except for some contaminated packs that DEC got from suppliers. Bankers Trust and Citibank on Wall Street used the product, taking 205MB RA60 packs across the river to New Jersey all day, via taxi cabs, as their defense against brown outs.

No successor product was released.

Additional information

1987 Disk/Trend Report, Hard Disk Drives

Edited by: T. Gardner

Contributors: G Saviers, Tom Burniece

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