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FIGURE 16-1 Ап example waveform of а broadcast АМ signal with 50
percent modulation.
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Note
AII the waveforms have the Xaxis denoting time and the Yaxis denoting amplitude.
(16-1 )
This equation describes the waveform in Figure 15-1, with the modulation т of the
carrier equal to 0.5, ог 50 percent. !f т = 100 percent, the carrier momentarily
drops to zero ог gets "pinched" off (Figure 15-2).
FIGURE 16-2 Ап АМ signal with 100 percent modulation.
Figure 15-2 shows ап АМ signal that has Ьееп modulated at а 100 percent level,
which pinches off the carrier but also allows the amplitude of the carrier to increase
to twice its level at О percent modulation. !п general, the equation governing the
standard АМ signal is