| |||
| ★ 方波电流 | |||
|
rectangular wave : 13 phrases in 8 subjects |
| Air defense | 3 |
| Construction | 1 |
| Electric machinery | 1 |
| Electronics | 2 |
| Geophysics | 1 |
| Metallurgy | 1 |
| Space | 1 |
| Technology | 3 |
| |||
| ★ 方波电流 | |||
|
rectangular wave : 13 phrases in 8 subjects |
| Air defense | 3 |
| Construction | 1 |
| Electric machinery | 1 |
| Electronics | 2 |
| Geophysics | 1 |
| Metallurgy | 1 |
| Space | 1 |
| Technology | 3 |