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Linę charging waveforms

The solution defined by equation 2.26 has the graph shown in Figurę 2.10. The fol łowi ng

observations may be madę about the diagram.

•    There is no activity at the load until the time T for a one-way propagation of signals on the linę has elapsed.

•    The initial step at that time is the product of two factors, one being the initially launched forward wave on the linę and the other being the sum of unity and the reflection factor at the load, this sum being known as the transmission factor at the load junction.

•    Although in this diagram it is shown that the initial step is to a voltagc less than the eventual load voltage, the factors controlling the size of this initial step are such that in sonie circumstances the step is to a value greater than the evcntual load voltagc.

•    Subsequcnt steps in the load voltagc occur at times 2T, 4T, etc. after the initial step, that is at total times 3T, 5T, etc.

•    Each of those subsequent steps is a common factor times the amplitudę of the preceding step. That common factor is the product of the reflection factors looking back toward the load and looking towards the source.

•    Those subsequent steps form a geometrical progression of which the common ratio happens to be positive in this illustration, but can be either positive or negative in the generał case.