الزمن: 57 phrases in 12 subjects |
Automatic control | 11 |
Electronics | 4 |
Lighting other than cinema | 1 |
Mathematics | 5 |
Physics | 2 |
Piezoelectric crystals | 3 |
Power lines | 3 |
Power system protection | 11 |
Radio | 3 |
Radiobiology | 1 |
Reliability | 10 |
Vacuum tubes | 3 |