c. prevent the modulated amplifier from oscillating.
d. prevent the grid from being driven to the zero grid bias point.
7. One favorable characteristic of a transmitter that uses low-level modulation
is that
a. nonlinear amplifiers can be used.
b. the transmitter has high efficiency.
c. audio-frequency power requirements are relatively low.
d. the modulating voltage is applied to the final power amplifier.
8. What are
the
two
types
of
modulation
that
are
combined
in
center
tap
modulation?
a. Plate and screen grid modulation
b. Plate and control grid modulation
c. Plate and suppressor grid modulation
d. Screen grid and control grid modulation
9. The proper phase relationships between input voltage, plate current, and
plate voltage appearing in a grounded-grid amplifier are shown in figure 2-1 in the
sketch labeled
a. A.
c. C.
b. B.
d. D.
10. One of the characteristics of a grounded-grid amplifier is that it
a. requires neutralization to prevent oscillation.
b. operates best on very high frequencies.
c. is best suited for use as a modulator.
d. needs very little RF driving power.
11. Speech amplifiers in radio transmitters often include design features that
accentuate certain frequencies in the usable speech range while attenuating all
other frequencies.
The primary purpose of this type circuit is to reduce the
bandwidth and
a. improve tonal quality.
b. retain intelligibility.
c. strengthen carrier power.
d. improve naturalness of speech.
321 L2
9
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