Sony Microsystems Ltd has duly launched its erasable magneto optic disk drive – together with the 5.25 disks to match – for its range of News workstations as briefly reported here last November. The NWP-539 is intended to combine the capacity and performance of optical storage systems with the erasibility of magnetic storage techniques. It can be used either stand-alone or on a machine that is part of a distributed network, other systems on the network can access the drive for both reading and writing. Sony claims to be the first manufacturer to offer such a drive together with disks – made possible by developments in magnetico-optic film technology and the high power lasers that enable high speed data transfer. The NWP-539 is housed in the NEWS-OS filesystem like a standard Winchester disk, storage capacity on a single sided disk is 297Mb – 594Mb on the double sided version. Data transfer is performed at 620Kb per second and average access time is a slow 90mS. The drive costs UKP2,500 and the double sided disks (which can’t be used on other machines) cost UKP130 each. This offering seems poised to bridge a gap between traditional magnetic media and full blown read-write optical storage systems. The latter remain somewhat unpopular because they are slow, yet seem set to eventually take over from other methods. Sony is currently reported to be in negotiation with other Japanese manufacturers about magneto-optic standards, presumably trying to ensure it does not get its fingers burnt again, like it did in the videotape world with its Betamax system.