 |
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| 标准频率和计时信号; 标频时号 | |||
| 标准频率与时间信号 | |||
| |||
| 标准频率和时间信号 | |||
| 校准频率和时间信号; 标频时号 | |||
| standard frequency and time signals: 5 phrases in 3 subjects |
| Space | 1 |
| Technology | 3 |
| Telecommunications | 1 |
|
| |||
| 标准频率和计时信号; 标频时号 | |||
| 标准频率与时间信号 | |||
| |||
| 标准频率和时间信号 | |||
| 校准频率和时间信号; 标频时号 | |||
| standard frequency and time signals: 5 phrases in 3 subjects |
| Space | 1 |
| Technology | 3 |
| Telecommunications | 1 |