c. frequency multipliers.
d. audio-correction network.
8. Most military FM transmitters are restricted to maximum frequency deviation
of 40 kHz.. If the maximum audio signal is 5 kHz, the modulation index is
a. 1/8.
c.
2.
b. 1/4.
d.
8.
9. Assume an FM station with a maximum carrier deviation of 40 kHz.
If the
modulation index (MI) is to be 5, the maximum audio frequency that can cause the
deviation is
a. 4 kHz.
c.
15 kHz.
b. 8 kHz.
d.
20 kHz.
10. Assume that one of your unit's FM transmitters has a 60-MHz carrier frequency
arid its frequency deviation must not exceed 40 kHz.
If the percentage of
modulation is 80 percent, the deviation is
a. 20 kHz.
c.
40 kHz.
b. 32 kHz.
d.
64 kHz.
11. Assume that a military FM transmitter is operating on a channel that extends
from 92.1 MHz to 92.2 MHz. Since military communication standards require a 10-kHz
guard hand on each end of the channel, the maximum permissible frequency deviation
is
a. 20 kHz.
c.
60 kHz.
b. 40 kHz.
d.
80 kHz.
12. An FM transmitter being modulated by a 10-kHz audio tone signal has an MI of
5.
If the MI is increased to 15 by increasing the amplitude of the modulating
signal, the effective bandwidth will be increased from
a. 40 kHz to 70 kHz.
b. 40 kHz to 160 kHz.
c. 160 kHz to 380 kHz.
d. 160 kHz to 480 kHz.
13. Assume that a commercial broadcast FM transmitter has a carrier frequency
(fc) of 97.400 MHz and is modulated with a 3-kHz signal.
A spectrum analysis
indicates that the highest significant frequency (fs) in the output is 97.475 MHz.
The MI of this transmitter is
a. 0.5.
c.
20.0.
b. 7.5.
d.
25.0
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