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these circuits, the end result of the electronic action within the integrated circuit is the same as it would be
with discrete components.
Q-38.
How does a low-pass filter detect pdm?
Q-39.
How is conversion used in pulse demodulation?
Q-40.
What is the discharge rate for the capacitor in a pcm converter?
SUMMARY
Now that you have completed this chapter, a short review of what you have learned is in order. The
following summary will refresh your memory of demodulation, its basic principles, and typical circuitry
required to accomplish this task.
DEMODULATION, also called DETECTION, is the process of re-creating original modulating
frequencies (intelligence) from radio frequencies.
The DEMODULATOR, or DETECTOR, is the circuit in which the original modulating frequencies
are restored.
A CW DEMODULATOR is a circuit that is capable of detecting the presence of rf energy.
HETERODYNE DETECTION uses a locally generated frequency to beat with the cw carrier
frequency to provide an audio output.
