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Fig. 18.1 {a) Sample of an amplitude-modulated carrier wave, similar to Fig. 15.1c.
The average value of each cycle is zero: but if one half of each is eliminated (b) the
average value of the other halves, shown dashed, fluctuates in the same manner as the
modulating waveform (e.g. Fig. \5.la)
The process of suppressing half of each cycle, converting
alternations of current into a series of pulses of unidirectional
current, is known by the general term rectification already met in
Sec.
5.5. The detector usually consists of a rectifier adapted to the
particular purpose now in view, and may be taken to include means
for extracting the desire ...