Code convertors for the interconnection of Morse and teleprinter systems

Abstract

Automatic convertors from international 5-unit teleprinter code to international Morse code, and vice versa, are described, different equipments being used for the two directions of conversion. Since the transmission speeds of teleprinter and Morse circuits are not, in general, the same, some form of storage is necessary when information in one code has to be received over a circuit, converted to the other code and retransmitted over another circuit. Morse (or Wheatstone) perforated tape is the form of storage adopted.Where an electro-mechanical device already in production could be simply modified to perform a function required in either of the convertors, it has been utilized in the designs. The input to the Morse-teleprinter code convertor is in the form of Morse perforated tape, and the tape-reading mechanism of a standard Morse printer has been adopted. Similarly, the selecting and perforating mechanism of a Morse keyboard perforator has been incorporated in the teleprinter-Morse convertor to provide the Morse perforated-tape output. The remainder of the equipment is mainly electronic, containing both thermionic and cold-cathode valves.