G09CCIPHERING OR DECIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHER PURPOSES INVOLVING THE NEED FOR SECRECYIn this subclass non-limiting references (in the sense of paragraph 39 of the Guide to the IPC) may still be displayed in the scheme. G09C1/00 G09C1/00Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system cryptographic typewriters G09C3/00 G09C1/02by using a ciphering code in chart form G09C1/04with sign carriers or indicators moved relative to one another to positions determined by a permutation code, or key, so as to indicate the appropriate corresponding clear or ciphered text G09C1/06wherein elements corresponding to the signs making up the clear text are operatively connected with elements corresponding to the signs making up the ciphered text, the connections, during operation of the apparatus, being automatically and continuously permuted by a coding or key member G09C1/08the connections being mechanical G09C1/10the connections being electrical G09C1/12comprising contact-bearing permutation discs G09C1/14involving removable or interchangeable coding numbers, e.g. master tapes, punched cards G09C3/00Typewriters for ciphering or deciphering cryptographic text marking record carriers G06K G09C3/02with auxiliary keys or keyboards acting on the original keys or keyboards G09C3/04wherein the operative connections between the keys and the type-bars are automatically and continuously permuted, during operation, by a coding or key member G09C3/06the connections being mechanical G09C3/08the connections being electrical G09C3/10involving removable or interchangeable coding members, e.g. master tapes, punched cards G09C5/00Ciphering apparatus or methods not provided for in the preceding groups, e.g. involving the concealment or deformation of graphic data such as designs, written or printed messages