 |
| |||
| 500/20-signalering | |||
| segnalazione: 165 phrases in 20 subjects |
| Agriculture | 1 |
| Communications | 42 |
| Electronics | 32 |
| Finances | 6 |
| General | 11 |
| Industry | 1 |
| Information technology | 20 |
| Law | 3 |
| Lighting other than cinema | 2 |
| Materials science | 4 |
| Mechanic engineering | 1 |
| Patents | 2 |
| Power lines | 1 |
| Radio | 1 |
| Rail transport | 1 |
| Technology | 1 |
| Telecommunications | 17 |
| Telegraphy | 2 |
| Telephony | 2 |
| Transport | 15 |