| |||
| frequenza vocale; audio m; frequenza fonica; frequenza telefonica | |||
| frequenza audio | |||
| audiofrequenza f; frequenza acustica | |||
|
Tonfrequenz : 14 phrases in 5 subjects |
| Communications | 4 |
| Electronics | 1 |
| Information technology | 4 |
| Measuring instruments | 1 |
| Radio | 4 |