| Subject | German | English |
| el. | amplitudenmodulierte Tonfrequenz-Telegraphie | amplitude modulation vf telegraphy |
| commun. | echtzeitnah kompandiertes Tonfrequenz-Multiplex | near-instantaneously companded audio multiplex (digital stereo TV sound system, GB) |
| IT, earth.sc. | Erkennen von Tonfrequenzen | detection of audio frequency |
| tech. | hohe Tonfrequenzen | treble (frequency) |
| automat. | Kommandosignale mit Tonfrequenz | command signals with audio frequency |
| IT, el. | Nummernwahl über Tonfrequenzen | electronic tone dialing |
| IT, el. | Nummernwahl über Tonfrequenzen | electronic tone dialling |
| tech. | Resonanz bei tiefen Tonfrequenzen | boom |
| commun., IT | Tastatur zur Nummernwahl über Tonfrequenzen | voice frequency dialling |
| commun., IT | Tastatur zur Nummernwahl über Tonfrequenzen | voice frequency dialing |
| tech. | Tonfrequenz-Amplitudenbegrenzer | audio peak limiter |
| commun. | Tonfrequenz-Hilfsträger | audio subcarrier |
| commun., el. | Tonfrequenz-Motor | phonic motor |
| meas.inst. | Tonfrequenz-Rufstrommessung | measurement of wire frequency ringing current |
| tech. | Tonfrequenz-Rundsteueranlage | AF ripple control system |
| radio | Tonfrequenz-Schutzabstand | AF protection ratio |
| radio | Tonfrequenz-Schutzabstand | audio-frequency protection ratio |
| tech. | Tonfrequenz-Spektrograph | audio frequency spectrograph |
| radio | Tonfrequenz-Störabstand | AF signal-to-interference ratio |
| radio | Tonfrequenz-Störabstand | audio-frequency signal-to-interference ratio |
| tech. | Tonfrequenz-Telegraphie | audio frequency telegraphy |
| commun. | Tonfrequenz-Uebertragung | voice frequency telegraphy |
| commun. | Tonfrequenz-Uebertragung | tone frequency telegraphy |
| commun. | Tonfrequenz-Uebertragung | carrier telegraphy |
| commun. | Tonfrequenz-Uebertragung | audio frequency telegraphy |
| IT | Tonfrequenz-Vierdraht-Schnittstelle | voice frequency interface 4-wire |
| IT | Tonfrequenzen-Sender-Empfänger-Einheit | frequency sender/receiver unit |
| commun., IT | Verwaltung der Tonfrequenzen | tone management |
| commun., IT | Zeichengabe mit Tonfrequenz | voice-frequency signalling |
| commun., IT | Zeichengabe mit Tonfrequenz | audio frequency signalling |
| commun., IT | Zeichengabe mit Tonfrequenz | voice-frequency signaling |
| commun., IT | Zeichengabe mit Tonfrequenz | audio frequency signaling |