ruggedized
| transistor
| ruggedising | |
| chem. | irrigidimento per pastiglie |
| transistor | |
| antenn. | triodo a cristallo |
| el. | transistore |
| |||
| irrigidimento per pastiglie | |||
|
ruggedized : 4 phrases in 3 subjects |
| Communications | 1 |
| Earth sciences | 1 |
| Electronics | 2 |