04443789 is referenced by 22 patents and cites 17 patents.

Disclosed herein is an electrical keyboard having five keys arranged conveniently for the fingers of an operators hand, a memory to store the signals from each key, logic circuit to instruct said stored data after release of the last of said keys and an encoder to receive said stored signals and produce electrical output signals corresponding to readable characters; each character signal requiring a single operation of a unique combination of said input keys for production of said signal.

Title
Keyboard
Application Number
542055
Publication Number
4443789
Application Date
November 13, 1981
Publication Date
April 17, 1984
Inventor
Christopher J Rainey
Croydon
GB
Cyril Endfield
London
GB
Agent
LeBlanc Nolan Shur & Nies
Assignee
Microwriter
GB
IPC
G06F 3/02
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