327 / | HD | MISCELLANEOUS ACTIVE ELECTRICAL NONLINEAR DEVICES, CIRCUITS, AND SYSTEMS |
100 | DF | SIGNAL CONVERTING, SHAPING, OR GENERATING {29} |
113 | DF | .~ Frequency or repetition rate conversion or control {3} |
117 | DF | .~.~ Frequency division {1} |
118 | .~.~.~ Having discrete active device (e.g., transistor, triode, etc.) |