 |
| resonance frequency: 50 phrases in 15 subjects |
| Air defense | 4 |
| Automobiles | 1 |
| Earth sciences | 1 |
| Electric machinery | 1 |
| Electronics | 8 |
| Engineering geology | 1 |
| Explosives and Explosive Ordnance Disposal | 2 |
| General | 1 |
| Metallurgy | 2 |
| Oil / petroleum | 2 |
| Piezoelectric crystals | 7 |
| Space | 1 |
| Technology | 16 |
| Telecommunications | 2 |
| Wind Energy | 1 |