Editing Scientific Data Systems (section)

==SDS in the United Kingdom==
In 1983 Ensor and Hill left Jacq-Rite and formed a company calling itself 'Scientific Data Systems UK Limited' or 'SDS UK' (but actually unrelated to SDS) in [[Crawley, West Sussex]] in the UK. This coincided with SDS's announcement of their 4000 series computer; they hoped to build a business around this machine (including supplying it to Jacq-Rite) and negotiated an exclusive arrangement with SDS.

The SDS 4000 was a complete re-design, both cosmetically and with all-new internal hardware, but the architecture was basically the same as the 400 series - and ran the same software. The machine had a 1/2 height {{frac|5|1|4}}-inch [[hard disk drive]] bay and used [[Seagate Technology|Seagate]] 10 and 20&nbsp;MB hard drives or [[SyQuest Technology|SyQuest]] removable drive units. The 4000 motherboard had a [[SCSI]] interface (still known as SASI at the time) and an [[Adaptec]] 4000 SASI controller board was shoe-horned into the case to connect the drives. The diskette drive was also half-height {{frac|5|1|4}}-inch (the 400 series had used 8 inch diskettes). Like the 410, there was a diskless version too. Local Area Networking capabilities were carried over from the 400 series.

The 4000's major aesthetic departure from its predecessor was the use of a separate 12-inch tilt-and-swivel [[Computer monitor|Visual Display Unit]] (VDU) and CPU case. The keyboard was detachable for the first time and the system had a beige colour scheme (dictated by the colour of the third party VDUs) in place of the black and white appearance of the 400.

However, financial problems at SDS were already substantial, and the UK business only ever received a small number of hastily completed machines. In an attempt to bypass these problems Hill produced a clone of the 4000 series computer by [[reverse-engineering]] an original model with the aid of a set of paper schematics obtained on a visit to SDS. This was neither approved nor supported by SDS, but Mitchell alone [and not Scheding] made a confidential visit to the UK to help debug the new computer. This was fortunate because, being unable to confer with SDS, Hill had unwittingly used schematics referring to a forthcoming revision of the machine, for which no [[firmware]] had yet been completed. Mitchell alone [and not Scheding] finished the new firmware at SDS UK's offices. This meant that Hill's 'unofficial 4000' was actually a later revision than any US machines completed. Hill also improved the board layout, rear-panel connectivity and power supply.

The new machine worked, and a number of examples were made using a prototyping firm in [[Poole, Dorset]]. Several were even sold, including a 5-station network with external storage (see below) to the UK [[Chartered Institute of Legal Executives|Institute of Legal Executives]] ('ILEX') in Bedford which remained in use for several years. This was supplied with bespoke software (also produced by Hill, with the assistance of Paula Flint) to store examination results and print certificates. However, any hope of selling into the lucrative Lloyd's insurance market in conjunction with Jacq-Rite was short-lived as Jacq-Rite had abandoned SDS and moved to the [[IBM PC]] platform, taking their customers with them, as soon as SDS UK was formed. (This decision was also influenced by John McCully, who was now developing his word-processing software for [[MS-DOS]].)

The 'unofficial' 4000 series machine was at least a finished computer, and the small number produced worked reliably. Taking advantage of the [[SCSI]] implementation, Hill added an external connector to his version of the machine and developed a matching hard drive enclosure. This enclosure accommodated higher capacity, full-height {{frac|5|1|4}}-inch drives.

However, the UK company's lack of [[Capital (economics)|capital]] to invest in the machine's manufacture meant that the cosmetic appearance of the computer left a lot to be desired. Furthermore, the machines were extremely costly – IBM's new [[PC/AT|Personal Computer/AT]] was shipping at about half the price SDS UK Limited needed to sell their computer for. Relationships between SDS and its UK namesake had broken down completely by this time, and SDS UK did not have the resources to develop new versions of the hardware or operating system.

SDS went out of business in the US 1984. The UK company of the same name ceased trading in the same year.