Mark 5 and Distributors were made by Systemation Developments Ltd – also in Brighton. Back to Top What mass storage was available?
The above answer is not quite correct about the Molecular 18 storage. Only the Molecular 18 MK1 used the front loading DRI D400/D800 disc drives. The M18 MK2, 3ME/6ME, MK4 and early MK5’s used the CDC Hawk designated the DD1600 and or the CDC multi platter drive designated D8000. The later MK5’s and the Distributor used the the CDC Lark
Mark One to Mark Three machines used a D400 front loading cartridge. Capacity of 875KB. The D800 was also available with doubled capacity – some 1.75MB. The DD800 had the same capacity as the D800, but was top loading, with a fixed disk inside the cabinet. (Much like the popular DD1600 referred to later.) Not often seen was the D8000 – this was a multi-platter disk pack, equivalent in both software and hardware to ten DD1600 packs bolted together! (I remember visiting a customer in Wembley with one of these drives, and being frightened witless by it!) Mark Four machines were normally supplied with CDC Hawk drives. (Code name DD1600) Up to four drives could be supported, but two was the usual. The Hawk drive had an internal 3.5M disk and an exchangeable top loading disk pack, also 3.5M. The two platters shared the same spindle, and the two sets of heads moved in synch. (Each sector was 128 x 17 bit words. i.e. 272 bytes per sector. The disk had 12992 sectors, equating to 3.5MB.) Mark Fi
