The CCITT,unanimously declares the view(1) that the number of characters that the line of text in page-printing equipment may contain should be fixed at 69;(2) that tape- or page-printing start-stop equipment should,with a view to interworking,be fitted with:a) two keys for the transmission of the carriage-return and line- feed signals;Note–New equipment may,in addition,be fitted with a single key for both carriage-return and line-feed,in accordance with the procedures described in Recommendation F.60 [1].b) means to draw attention of the operator to the need to transmit carriage-return and line-feed signals in time to prevent overprinting on the 69th character;Note–New equipment may,in addition,be fitted with means preventing the input of any printing character after the 69th character of a line.This condition is signalled to the operator optically and/or acoustically.The carriage-return function cancels the signal and releases the input of characters.
ITU-T S.5-1988 Referenced Document
ITU-T F.60 Operational Provisions for the International Telex Service (Study Group I) 34 pp*， 1992-01-01 Update
ITU-T S.5-1988 history
1988ITU-T S.5-1988 STANDARDIZATION OF PAGE - PRINTING START - STOP EQUIPMENT AND COOPERATION BETWEEN PAGE - PRINTING AND TAPE - PRINTING START - STOP EQUIPMENT (ITA2)