Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!lll-winken!netsys!vector!telecom-gateway
From: clements@bbn.com
Newsgroups: comp.dcom.telecom
Subject: 5-level TTY code (was Re: The 'Public Telegraph Office')
Message-ID: <telecom-v09i0426m08@vector.dallas.tx.us>
Date: 3 Oct 89 18:41:56 GMT
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X-TELECOM-Digest: volume 9, issue 426, message 8 of 8

andyb@coat.com writes:
>[In the code used on 5-level TTY machines] The most common letters
>of the English alphabet (ETAIONSHRDL....) and the word separators
>(space, return, line feed) have the codes with the fewest number of
>marking bits.
>
>Does anyone know why this is so?

To minimize the wear on the pins in the paper tape punches.
(I know, I've refurbished a number of those punches in my day.)

Bob Clements, K1BC, clements@bbn.com