multi-frequency code
| signalling
| multi-frequency code abbr. | |
| telecom. | 多频编码 |
| signalling abbr. | |
| hydroel.st. | 信号设备; 发信号 |
| met. | 信号; 通信 |
| space | 发码; 信号传输; 信令 |
| tech. | 直流振铃 |
| |||
| 多频编码 | |||
|
multi-frequency code : 5 phrases in 2 subjects |
| Space | 1 |
| Telecommunications | 4 |