website/content/museum/shelton-instruments-sig-net.md

title, categories, types, origins, years, cpus, params

title	categories	types	origins	years	cpus	params
SHELTON INSTRUMENTS Sig-Net	Computers	Professional Computer	United Kingdom	1981	Z80-A	name image company company_name specs comments oc_id source Sig-Net /media/museum/photos/shelton_signet_system_1.jpg /companies/shelton-instruments SHELTON INSTRUMENTS label value NAME Sig-Net label value MANUFACTURER Shelton Instruments label value TYPE Professional Computer label value ORIGIN United Kingdom label value YEAR 1981 label value BUILT IN LANGUAGE None label value KEYBOARD Depending on the video terminal used label value CPU Z80-A (or B) label value SPEED 4 MHz. label value CO-PROCESSOR None label value RAM 64 KB to 128 KB (one-processor system) label value ROM 4 KB label value GRAPHIC MODES A graphic card was available - Features unknown label value SOUND Beeper label value SIZE / WEIGHT Unknown label value I/O PORTS 2 x Serial RS232, 1 x Parallel Centronics label value BUILT IN MEDIA 1 to 4 200, 400 or 800 KB 5'' floppy disc drives label value OS CP/M label value POWER SUPPLY Built-in power supply unit + one power supply per card label value PERIPHERALS Optional 7 MB hard disk (£3300 + £600 for the controller) label value PRICE Basic version (200/2) about $2900 + video terminal author date text Ross Milbourne (United Kingdom) Monday 26th October 2020 I own a Shelton Signet 200 cabinet, with twin floppy disk drives built-in and a separate monitor. I am trying to find out if anyone has a copy of CP/M, or other software for this machine please? Best wishes, Ross author date text Jayesh Shah (london) Friday 17th April 2020 I used to build the signets. I started working with Chris Shelton in 1981 building the signet3 systems and was the main person doing customer support. It was very sad to see the end of the signet in 1994. I was the only one from the early years still supporting the product. I ended up buying all the stock, some 300 units in various forms and provided support to the various end users still using the Signet3 multiuser systems. I would love to hear from any one who might have spoken to me. author date text gary smith (United Kingdon) Sunday 1st July 2018 I spent many years programming and selling Shelton Sig-net they were designed by a guy called Chris Shelton of Shelton Instruments and they had CPM operating system. I used to program in Microsoft Compiled Basic and the biggest system I sold was a 48 user to Sunseeker Travel in Huddersfield in 1988. Originally it was one processor per screen all connected to a hard disk using sheltons purpose designed ringring system which was a bus between the processors and the z80 running the hard disk. Rhodime made in scotland in 7/14/21 megabytes that formated down to 5/10/15 MB. I have lots more information if your interested. author date text Webmaster (France) Saturday 5th June 2010 It would be nice if you could send us some pictures of this rare system! author date text Dylan Malama Saturday 5th June 2010 I Currently own one of these-\ without a diskette drive. The case to this machine is easy to remove because it has a little button you can push to unlock it. I''ve been trying to find out who made my system$ and this is the same exact model. thanks old-computers.com! 810 url date https://web.archive.org/web/20230528100258/http://www.old-computers.com/museum/computer.asp?c=810 2023-05-28

Shelton Instruments were the people behind the original design of the Nascom 1. They were based in London.

Sig-Net was a totally new concept, whereby a series of boards - processor, interface, memory, etc. - were interconnected by flexible wires.

Each board had its own power supply and many variations of computer could be evolved from the basic system components.

The Sig-Net 200 series computer had a number of these modules housed in an enclosure that can have two integral floppy disc drives. The system came with 64 KB of RAM and up to 4 KB of ROM. There were two RS232 interfaces and a 4-channel real-time clock.A hard disk controller could be connected on-board.

The system was indefinitely expandable, even to a multi-processor system, using Sig-Net modules. CP/M 2.2 operating system came with the computer allowing the vast CP/M library of software to be used.