{"id":224,"date":"2019-06-09T21:00:52","date_gmt":"2019-06-10T02:00:52","guid":{"rendered":"https:\/\/www.computercollection.net\/?page_id=224"},"modified":"2021-03-26T12:42:30","modified_gmt":"2021-03-26T17:42:30","slug":"disk-drives","status":"publish","type":"page","link":"https:\/\/www.computercollection.net\/index.php\/disk-drives\/","title":{"rendered":"Minicomputer Disk Drives"},"content":{"rendered":"\n

My collection has a fair number of floppy disk and disk drives on both minicomputers and microcomputers. For the most part, the microcomputer drives are not pictured here, but are instead pictured with their individual microcomputers.<\/p>\n\n\n\n

Digital Equipment RX01<\/a><\/h2>\n\n\n\n
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Digital Equipment RX01 Dual Floppy Drive<\/figcaption><\/figure>\n\n\n\n

The RX01 is an “interesting” device. It has a DEC formatter board which does most of the work, and a relatively simple, non-DMA interface on the computer side. It handles single density IBM-3740 format compatible floppy disks. DEC also made a double-density RX02 – but it recorded the first track in single density.<\/p>\n\n\n\n

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Diablo Model 30 \/ DEC RK03<\/a><\/h2>\n\n\n\n
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Diablo Model 30 \/ DEC RK03 Disk Drives<\/figcaption><\/figure>\n\n\n\n

Before Digital Equipment came up with the RK05 disk drive, they used a Diablo Model 30 drive, which was used by other minicomputer manufacturers as well. Those two – the RK03 and RK05 – are compatible and can interchange packs. Each pack stores about 2.4MB of information. It’s track to track seek time was a respectable 15ms, with an average seek time of 70ms. This pair are part of Hannes’ PDP-11\/20<\/a>, and sports the older RK11-C controller. At one time they were working, and one still did spin up the last time I tried it. There may be power supply issues.<\/p>\n\n\n\n

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Digital Equipment RK05<\/a><\/h2>\n\n\n\n