Editing Scientific Data Systems (section)

==A new start==
Former SDS employees restarted the company with funding from Max Palevsky, Sanford Kaplan, Dan McGurk, and others in 1979. Jack Mitchell, William L. Scheding, and Henry Harold, along with some other former SDS engineers introduced a microprocessor-based computer called the SDS-420<ref>{{cite news|last1=Rosenberg|first1=Marcy|title=SDS Resurfaces With Same Name, New Target|url=https://books.google.com/books?id=sglMaWvdPEUC&q=%22SDS+420%22&pg=RA1-PA111|access-date=Nov 6, 2015|work=Computerworld|volume=XIII|issue=7|date=Feb 12, 1979|archive-date=September 9, 2023|archive-url=https://web.archive.org/web/20230909011940/https://books.google.com/books?id=sglMaWvdPEUC&q=%22SDS+420%22&pg=RA1-PA111|url-status=live}}</ref> built on a [[MOS Technology 6502|6502A-based]] processor design with up to 56&nbsp;KB of memory and a proprietary OS, SDS-DOS, along with the [[BASIC programming language]] from [[Microsoft]]. The SDS-420 featured a dual single-sided-double-density (400&nbsp;KB per side) [[floppy disk]] drive, Model 70, manufactured by PerSci (Peripheral Sciences), of [[Santa Monica, California|Santa Monica]] and [[Marina del Rey, California|Marina del Rey]], California. The SDS-422 Model offered some of the first dual double-sided-double-density floppy drives. Other hardware options were a [[MOS Technology 6551|6551]]-A [[Universal synchronous and asynchronous receiver-transmitter|USART]] and a proprietary network SDS-NET using a [[Zilog SCC|Z8530]] SDLC/HDLC chip and software patterned after the early Xerox 3.0&nbsp;[[Mbit/s]] [[Ethernet]] and [[transceiver]]s produced by Tat Lam of the Bay Area.

The company sold about 1,000 machines worldwide, including Tahiti, London, Italy, New York City and Los Angeles. The 400 Series had little to do with [[scientific computing]] and more with word processing and business services.

SDS announced a fully operational [[local area network]] (LAN)-based [[file server]] called SDS-NET at [[COMDEX]] in the early 1980s. SDS-NET was based on a Model 430 and written by Sam Keys, of [[Westchester, California]]. The SDS 430 Server offered [[file sharing|file]] and [[printer sharing]] services over SDS-NET or using a [[modem]] and was based upon a 10&nbsp;MB hard disk manufactured by Micropolis of Chatsworth, California. SDS Offered other models, including the SDS-410, a [[diskless workstation]] that booted and ran off the SDS-NET or optionally could boot off-of and run over a 1200 bit/s modem link.

Products offered were: Word (word processing, written by John McCully, formerly of [[A M Jacquard Systems|Jacquard Systems]], [[Manhattan Beach, California]]), and fully functional accounting software: balance-forward and open-item accounting with [[General Ledger]], [[Accounts Receivable]], [[Accounts Payable]], and [[Payroll]] (written by Tom Davies and Sandra Mass, both formerly with Jacquard Systems).

Other offerings included: Legal Time and Billing, Medical Time and Billing, and ''TTY'' an early terminal emulation program using the 6551 USART. Through partnerships with their [[value-added reseller]]s (VARs) other software product offerings included a [[solid-waste management]] system with automated truck routing and a country-club accounting package. One UK-based VAR was Jacq-Rite, a vertical market software house run by Ken Groome and Vivienne Gurney and based in [[Dorking]], [[Surrey]]. Jacq-Rite had developed a range of specialist insurance software for the Jacquard machine but transferred to the SDS 400 following the advice of John McCully. Jacq-Rite installed several SDS 400 series networks in [[Lloyd's]] Managing and Members Agencies during 1982 and 1983. One of Jacq-Rite's programming staff that worked on the software porting was Justin Hill. Jacq-Rite's hardware sales were managed by David Ensor.