| signal | |
| commun. life.sc. | beacon |
| comp., MS | beacon; cellular signal |
| life.sc. | ground target; terrestrial target |
| mus. | signal |
|
RF : 80 phrases in 10 subjects |
| Chemistry | 2 |
| Communications | 24 |
| Earth sciences | 1 |
| Electronics | 38 |
| General | 1 |
| Health care | 2 |
| Information technology | 6 |
| Natural sciences | 1 |
| Social science | 1 |
| Technology | 4 |