| |||
| operation and maintenance signal | |||
| |||
| orderwire signal | |||
|
signal d'exploitation : 5 phrases in 3 subjects |
| Communications | 2 |
| Electronics | 1 |
| Information technology | 2 |
| |||
| operation and maintenance signal | |||
| |||
| orderwire signal | |||
|
signal d'exploitation : 5 phrases in 3 subjects |
| Communications | 2 |
| Electronics | 1 |
| Information technology | 2 |