327 / | HD | MISCELLANEOUS ACTIVE ELECTRICAL NONLINEAR DEVICES, CIRCUITS, AND SYSTEMS |
100 | DF | SIGNAL CONVERTING, SHAPING, OR GENERATING {29} |
172 | DF | .~ Rectangular (e.g., clock, etc.) or pulse waveform width control {5} |
177 | .~.~ Having inductive device (e.g., transformer, etc.) |