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ASSIGNMENT 3
Textbook assignment: Chapter 3, “Demodulation,” pages 3-1 through 3-35.
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3-1. The process of recreating the original
modulating frequencies (intelligence)
from an rf carrier is known by which of
the following terms?
1. Detection
2. Demodulation
3. Both 1 and 2 above
4. Distribution
3-2. When a demodulator fails to accurately
recover intelligence from a modulated
carrier, which of the following types of
distortion result?
1. Phase
2. Frequency
3. Amplitude
4. Each of the above
3-3. In a demodulator circuit, which of the
following components is required for
demodulation to occur?
1. A linear device
2. A nonlinear device
3. A variable resistor
3-4. In cw demodulation, the first requirement
of the circuit is the ability to detect
1. the presence or absence of the carrier
2. amplitude variations in the carrier
3. frequency variations in the carrier
4. phase variations in the carrier
Figure 3A.—Cw demodulation.
IN ANSWERING QUESTION 3-5, REFER TO
FIGURE 3A.
3-5. In the figure, L and C1 form a frequency-
selective network that serves what
purpose?
1. It removes the carrier
2. It rectifies the oscillations
3. It tunes the circuit to the desired rf
carrier
4. It provides filtering to maintain a
constant dc output
3-6. To aid in distinguishing between two or
more cw signals that are close to the
same frequency, which of the following
detectors is used?
1. Diode
2. Crystal
3. Heterodyne
4. Transistor
