| |||
signaling system | |||
signalling system | |||
| |||
signaling system 7 | |||
| |||
R1 | |||
| |||
R2 |
信令系统 : 88 phrases in 13 subjects |
Air defense | 3 |
Aviation | 10 |
Business | 2 |
Communications | 1 |
Computer networks | 3 |
Earth sciences | 1 |
Electronics | 40 |
General | 2 |
Information technology | 4 |
Space | 5 |
Technology | 1 |
Telecommunications | 15 |
United States | 1 |