| |||
| NU tone; number-unobtainable tone; information tone; tone; n.u.tone; special information tone | |||
| number unobtainable tone | |||
|
informatietoon : 2 phrases in 2 subjects |
| Communications | 1 |
| Electronics | 1 |
| |||
| NU tone; number-unobtainable tone; information tone; tone; n.u.tone; special information tone | |||
| number unobtainable tone | |||
|
informatietoon : 2 phrases in 2 subjects |
| Communications | 1 |
| Electronics | 1 |