Epson HC-20 (HX-21-UA)

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The Epson HC-20 (also known as the HX-20 in the rest of the world) is regarded by some as the first laptop computer. It was invented in 1980 by Yukio Yokozawa, who worked for Suwa Seikosha, a branch of Japanese company Seiko (now Seiko Epson), receiving a patent for the invention. In 1981 it was announced as the HC-20 in Japan, and the HX-20 at the COMDEX computer show in Las Vegas, and went on sale in Japan and worldwide the following year. A lack of software and distribution meant it was not sold widely until 1983. It was hailed by BusinessWeek magazine as the "fourth revolution in personal computing".

The HX-20 was advertised as the "world's first 'note-book size' portable computer"; despite being the same size as an A4 sheet of paper and weighing 4lb [1.8kg], the computer housed a full-size keyboard, built-in display and printer. It was priced at under £500, and aimed at the business user. The LCD screen provided 20-character by 4-line display with a 120 x 32 dot graphics resolution. The built-in inked-ribbon matrix printer prints graphics and upper- and lower-case characters. The space to the right of the screen can be occupied by either a microcassette drive for program or data storage, or a plug-in ROM cartridge. The built-in NiCad batteries had a battery life of about 50 hours before they needed to be recharged.

The system came with 16K RAM, which can be expanded to 32K, and 32K ROM containing Microsoft Basic and the operating system. The HX-20 uses two 6301 processor chips from Hitachi, one to look after all I/O and housekeeping tasks, and the other for language processing. The computer was also equipped with a date and time clock, audio cassette interface, built-in speaker, RS-232C port, high speed serial interface and a barcode reader port for greater versatility in special applications.

Our HC-20 is clearly marked on the back as model number HX-21-UA with a date of 19th October 1986. It has a serial number of 002 on a label marked "Epson Sample".

Manufacturer: Epson
Date: 19th May 1986

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Magazines RELATED to Epson HC-20 (HX-21-UA) in our Library

Item Manufacturer Date
Personal Computer World - December 1982 Dec 1982

Other Systems Related To Epson HC-20 (HX-21-UA):

Item Manufacturer Date
Epson HX-20 Epson November 1981
Epson Executive HX-20 Epson 1982
Epson HX-20 with Hard Case Epson November 1982
Epson QX-10 Epson 1983
Epson PX-8 Epson 1984
Telsoft Epson PX-8 Computer + Epson P80-X Printer in Samsonite Case Telsoft Epson 1984
Epson PX-4 Epson 1985
Epson PX-4B Epson 1985
Epson PC-Portable Q150A Epson 1989
Epson Equity LT Epson 1989
Epson PC Club PC-286C Epson 1990

This exhibit has a reference ID of CH7038. Please quote this reference ID in any communication with the Centre for Computing History.


Epson HC-20 (HX-21-UA)

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