| |||
| secondary echo | |||
| |||
| reflected echo | |||
|
отраженное эхо : 5 phrases in 4 subjects |
| Antennas and waveguides | 1 |
| Electronics | 1 |
| Military | 1 |
| Nautical | 2 |
| |||
| secondary echo | |||
| |||
| reflected echo | |||
|
отраженное эхо : 5 phrases in 4 subjects |
| Antennas and waveguides | 1 |
| Electronics | 1 |
| Military | 1 |
| Nautical | 2 |