Tom
10-23-2002, 09:02 AM
IPC Advanced Study Guide Page Reference: Pages 237 - 238, Section 4.9
The coupling due to capacitive effects (electric field energy) causes a small reproduction of the active signal to be sent to both the far and near ends of the receptor line. The capacitively coupled pulses are the same polarity as the signal in the source line.
The inductive coupling (magnetic field energy) causes a signal of the same polarity as the source signal to be coupled to the near end of the receptor and a signal of the opposite polarity as the source signal to be coupled to the far end of the receptor.
Since the capacitively coupled energy, at the near end of the receptor, is the same polarity as the inductive energy, the two pulses add together. Hence the backward crosstalk is much larger per unit length of coupling than the forward crosstalk, which consists of the difference between the inductive and capacitive energy.
The coupling due to capacitive effects (electric field energy) causes a small reproduction of the active signal to be sent to both the far and near ends of the receptor line. The capacitively coupled pulses are the same polarity as the signal in the source line.
The inductive coupling (magnetic field energy) causes a signal of the same polarity as the source signal to be coupled to the near end of the receptor and a signal of the opposite polarity as the source signal to be coupled to the far end of the receptor.
Since the capacitively coupled energy, at the near end of the receptor, is the same polarity as the inductive energy, the two pulses add together. Hence the backward crosstalk is much larger per unit length of coupling than the forward crosstalk, which consists of the difference between the inductive and capacitive energy.