Modern Electronic Communication by Gary Miller Chapter 5 with Answers

Chapter 5: Frequency Modulation Transmission

1	Angle modulation includes the following types of modulation:
	a. FM
	b. PM
	c. AM
	d. All the above
	e. a and b
2	The amount of frequency increase and decrease around the center frequency in an FM signal is called the
	a. Index of modulation
	b. Frequency deviation
	c. Phase deviation
	d. Bandwidth of the FM signal
3	The amount of frequency deviation is dependent on the intelligence frequency in
	a. An FM signal
	b. A PM signal
	c. Both FM and PM signals
	d. Neither FM nor PM signals
4	An FM signal has an intelligence frequency of 2 kHz and a maximum deviation of 10 kHz. If its carrier frequency is set at 162.4 Mhz, what is its index of modulation?
	a. 10
	b. 5
	c. 2
	d. 20
5	The amount an FM carrier frequency deviates for a given modulating input voltage level is called the
	a. Frequency deviation
	b. Index of modulation
	c. Deviation constant
	d. Deviation ratio
6	Standard FM broadcast stations use a maximum bandwidth of
	a. 150 kHz
	b. 200 kHz
	c. 75 kHz
	d. 15 kHz
7	Carson's rule is used to approximate the necessary
	a. Frequency deviation
	b. Bandwidth
	c. Capture ratio
	d. Modulation index
8	An FM transmitter has an output power of 500 W when it is not modulated. When intelligence is added, its modulation index is 2.0. What is its output power with a modulation index of 2.0?
	a.  250 W
	b. 500 W
	c. 1000 W
	d. 2000 W
9	Another way to describe the modulation index is using the
	a. Deviation ratio
	b. Deviation constant
	c. Capture ratio
	d. Maximum deviation
10	The inherent ability of FM to minimize the effect of undesired signals operating at the same or nearly the same frequency as the desired station is known as the
	a. Capture effect
	b. Signal-to-noise ratio
	c. Noise figure
	d. Bessel function
11	In a Crosby FM transmitter, an FM signal having a center frequency of 2.04 Mhz and a deviation of 69 Hz is passed through four cascaded frequency multiplier stages: two triplers, one doubler, and one quadrupler. What type of signal appears at the output of the last multiplier stage?
	a. Center frequency of 2.04 Mhz and deviation of 4.96 kHz
	b. Center frequency of 146.88 Mhz and deviation of 4.96 kHz
	c. Center frequency of 2.04 Mhz and deviation of 69 Hz
	d. Center frequency of 146.88 Mhz and deviation of 69 Hz
12	The circuitry used to increase the operating frequency of a transmitter up to a specified value is called the
	a. Multiplier
	b. Expander
	c. Pump chain
	d. All the above
13	The purpose of the matrix network in a stereo FM broadcast transmitter is to
	a. Mix the 38-kHz pilot carrier with the L – R audio
	b. Convert the L and R channels to L + R and L – R channels
	c. Separate the left channel from the right channel
	d. Modulate the L + R and L – R signals with the carrier signal
14	An FM signal has an intelligence frequency of 5 kHz and a maximum deviation of 25 kHz. Its index of modulation is
	a. 125
	b. 0.2
	c. 5
	d. 6
15	Frequency multipliers
	a. Are used to multiply the frequency of the carrier signal of an FM signal
	b. Consist of a class C amplifier followed by a tank circuit that filters out a single harmonic
	c. Are used to multiply the frequency deviation of an FM signal d. All of the Above Answers: E B B B C B B B A A B C B C D