hard drive history

smaller, faster: early 3.5 inch drives

Kalok Octagon KL-230

Photo: Red Hill.

Kalok Octagon KL-230

Kalok was founded by a former Seagate engineer, the same man who had been largely responsible for the pioneering ST-225. Kalok seemed to live on the edge of bankruptcy most of the time, and later morphed into JTS.

Like all Kalok drives, the KL-230 had a dreadful reputation in the trade but we always found that this model went OK. We never saw new ones, only second-hand examples, so maybe all the duds had already expired by then!

Picture: A Kalok Octagon 330 — essentially an RLL certified 230 — with Western Digital 1002A-WX1 MFM XT controller. Western Digital had missed out on the biggie — the IBM contract for the PC-XT, but the company soon established itself in the industry as the hard drive controller manufacturer of choice.

Data rate5 Mbit/secSpin rate3600 RPM
Seek time48msActuatorStepper
Platter capacity10.5MBInterfaceMFM
AT drive type2 or 6Form3.5" half-height
KL-23021MB4 thin-film heads
KL-33030MB4 thin-film heads