| 324 / | HD | ELECTRICITY: MEASURING AND TESTING |
| 600 | DF | IMPEDANCE, ADMITTANCE OR OTHER QUANTITIES REPRESENTATIVE OF ELECTRICAL STIMULUS/RESPONSE RELATIONSHIPS {8} |
| 629 | DF | .~ Distributive type parameters {6} |
| 637 | DF | .~.~ Using transmitted or reflected microwaves {3} |
| 642 | DF | .~.~.~ Where energy is reflected (e.g., reflectometry) {4} |
| 644 | ![]() | .~.~.~.~ To determine dimension (e.g., distance or thickness) |