signal is required?
a.
Heterodyne method
c.
Basic modulation method
b.
Phase-lock method
d.
Harmonic generation method
7. A common
method
of
generating
harmonics
is
to
apply
the
fundamental
frequency to a
a.
fixed filter.
c.
nonlinear device.
b.
variable filter.
d.
stabilized master oscillator.
8. Assume that the frequency of the input generator in the circuit shown in
figure 3 of IT 51048 is changed from 4 kHz to 3 kHz. The harmonic filters would
have to be changed to pass the output frequencies of
a.
3, 4, 6, and 8 kHz.
b.
3, 6, 9, and 12 kHz.
c.
6, 9, 12, and 15 kHz.
d.
6, 10, 14, and 18 kHz.
9. A multivibrator is a good source of a square-wave signal.
One reason for
using a square-wave signal source in a frequency synthesizer is to produce an
output signal that is
a.
free from noise.
c.
rich in odd harmonics.
b.
extremely stable.
d.
rich in even harmonics.
10. The typical synthesizing circuit that uses the heterodyne method is divided
in three sections. These three sections are the
a.
1st mixer, 2d mixer, and 400-kHz amplifier.
b.
harmonic generating section, filter section, and output section.
c.
harmonic amplifier section, 10-kHz multivibrator section, and 100-kHz
oscillator section.
d.
filter section,
output
amplifier
section,
and
carrier
oscillator
section.
11. The output signal from the carrier oscillator is used in two stages of the
heterodyne-type frequency synthesizer (fig. 6). These two stages are the
a.
400-kHz amplifier and second mixer.
b.
first mixer and harmonic amplifier.
c.
second mixer and tuned amplifier.
d.
first mixer and second mixer.
327 L1
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