 |
|
signal lights : 93 phrases in 14 subjects |
| Aviation | 1 |
| Chemistry | 1 |
| Communications | 28 |
| Construction | 3 |
| Electronics | 5 |
| General | 6 |
| Lighting other than cinema | 1 |
| Natural sciences | 1 |
| Nuclear physics | 2 |
| Rail transport | 7 |
| Road works | 1 |
| Telecommunications | 3 |
| Transport | 33 |
| Vacuum tubes | 1 |