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Raw Blame History

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

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SHELTON INSTRUMENTS Sig-Net

Computers

Professional Computer

United Kingdom

1981

Z80-A

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Sig-Net

/media/museum/photos/shelton_signet_system_1.jpg

/companies/shelton-instruments

SHELTON INSTRUMENTS

label	value
NAME	Sig-Net

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MANUFACTURER	Shelton Instruments

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TYPE	Professional Computer

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ORIGIN	United Kingdom

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YEAR	1981

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BUILT IN LANGUAGE	None

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KEYBOARD	Depending on the video terminal used

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CPU	Z80-A (or B)

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SPEED	4 MHz.

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CO-PROCESSOR	None

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RAM	64 KB to 128 KB (one-processor system)

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ROM	4 KB

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GRAPHIC MODES	A graphic card was available - Features unknown

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SOUND	Beeper

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SIZE / WEIGHT	Unknown

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I/O PORTS	2 x Serial RS232, 1 x Parallel Centronics

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BUILT IN MEDIA	1 to 4 200, 400 or 800 KB 5'' floppy disc drives

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OS	CP/M

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POWER SUPPLY	Built-in power supply unit + one power supply per card

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PERIPHERALS	Optional 7 MB hard disk (£3300 + £600 for the controller)

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PRICE	Basic version (200/2) about $2900 + video terminal

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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.

2.5 KiB Raw Blame History

2.5 KiB

Raw Blame History