GB818770A - Teleprinter apparatus - Google Patents

Abstract

818,770. Type-printing telegraphy. STANDARD TELEPHONES & CABLES Ltd. Nov. 29, 1957 [Dec. 4, 1956; Dec. 5, 1956], No. 37291/57. Class 40 (3). In teleprinter apparatus, a transmitter effecting transmission by the normal international teleprinter code is arranged to transmit a third shift signal and to transmit in this third case - shift group only those signal combinations having one definite ratio or a limited number of definite ratios between the mark and space elements of the combinations. The third shift signal may be constituted by, for example, the figure - shift signal followed by the letter G, which has no assigned upper case character, or preferably by the allblank signal, and is effective to move a typewheel to a position in which printing is effected from a third row of type. The figures 0 ... 9 may be sent as combinations in the third case group with 2 marks and 3 spaces, and the arrest of the type-wheel in a position corresponding to any other code combination results in an error sign being printed, preferably in red. When an error sign is printed, an alarm circuit may also be actuated. Additionally, signs, such as +, -, may be sent in the third case group as signal combinations with 4 marks and 1 space, all combinations other than those for the signs and numerals resulting in the printing of the error sign and the opertion of the alarm. In the column 3b, numerals are represented by combinations with 3 marks and the special signs have 1 mark and 4 spacing elements.