| Subject | English | German |
| IT | multifrequency code | Mehrfrequenzencode |
| commun. | multifrequency code | Mehrfrequenz-Code (PCM signalling) |
| IT | multifrequency code | Vielfachfrequenzcode |
| tech. | multifrequency code | Mehrfrequenzcode |
| commun. | multifrequency code signalling | Mehrfrequenz-Code-Zeichen (PCM signalling) |