| English | German |
| common-frequency method | Frequenzgleichlageverfahren |
| dual tone multi-frequency DTMF; dialling method | Multifrequenzwählverfahren (CCITT Yellow Book Vol. VI. 1 Recommendation Q.23) |
| dual tone multi-frequency DTMF; dialling method | Multifrequenzverfahren (CCITT Yellow Book Vol. VI. 1 Recommendation Q.23) |
| dual-tone multi-frequency DTMF method | Mehrfrequenz-Verfahren |
| frequency synthesis method | Frequenzsynthese |