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FIGURE  16-1  Ап example  waveform  of  а broadcast  АМ signal  with  50

            percent modulation.


                                                     ~
                                                      -
                                                         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
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