Page 265 - Build Your Own Transistor Radios a Hobbyists Guide to High-Performance and Low-Powered Radio Circuits
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            FIGURE  15-9 Result of sampling the peak amplitude of the phase-shifted
            input signal.
            Figuгe 15-9 shows that sampling  the input signal that has  Ьееп phase-shifted to 90
            degгees гesu lted in  а tгai n of pulses  whose  pulse  amplitude  is  the  peak amplitude
            of the  input signal (e.g.,  one-half).  50,  even  though the  input signal's  fгequency is
            the same  as  the sampling f:requency,  the phase shift of 90  degrees in this example

            is equivalent to ап input signal set to 0.5 volt  DC.
            Now  let's see  what  happens  when  the  input signal is  phase-shifted  fuгther (Figure
            15-10).  As  seen  in  the  figuгe, the  input  signal  is  phase-shifted  Ьу 270  degгees,
            causing  the  sampling  pulses  to capt1ure the  negative  peaks  of the  input sine-wave

            signal.  Аgа i п,  the  peak  amplitude  of the  i прut signal  is  one-half the  pulse's
            amplitude.  Figuгe 15-11 shows the  гesult of saimpling the  270-degгee phase-shifted
            signal.
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