Modern Electronic Communication by Gary Miller Chapter 7 with Answers

Chapter 7 Communication Technique

1	Why are image frequencies somewhat less of a problem in FM receivers than they are in SSB or AM receivers?
	a. SSB uses less bandwidth than does FM.
	b. FM signals have a capture effect characteristic.
	c. FM mixer stages are square-law devices.
	d. FM receivers do not use the superheterodyne design.
2	The tuned circuits prior to the mixer in a superheterodyne receiver are called the
	a. Front end
	b. Tuner
	c. Preselector
	d. All the above
3	The signal-strength meter that shows the relative signal-strength level is called the ________ .
	a. S meter
	b. Signal meter
	c. Strength meter
	d. All the above
4	An AM broadcast receiver has two identical tuned circuits with a Q of 50 prior to the IF stage. The IF frequency is 460 kHz and the receiver is tuned to a station on 550 kHz. The image-frequency rejection is
	a. 41 dB
	b. 36.2 dB
	c. 72.4 dB
	d. 82 dB
5	An AGC that causes a step reduction in receiver gain at some arbitrarily high value of received signal in order to prevent overloading the receiver is known as
	a. Arbitrary AGC
	b. Auxiliary AGC
	c. Delayed AGC
6	Up-conversion offers the following advantage(s):
	a. Less expensive filters
	b. Good image-frequency rejection
	c. Minimized tuning range for the LO
	d. .b and c
7	The range over which the input to a receiver or amplifier provides a usable output is called the
	a. Level of acceptability
	b. Dynamic range
	c. Degree of usefulness
	d.Specified input
8	A receiver has a 30-dB noise figure, a 1.5 Mhz bandwidth, a 6-dBm third intercept point, and a 3-dB signal-to-noise ratio. Its sensitivity is
	a. –94 dB
	b. –82.2 dB
	c. –79.2 dB
	d. –81 dB
9	Two-modulus dividers are used in the synthesis of frequencies into the VHF band due to
	a. Its ability to work at practical power consumptions
	b. Its ability to work at practical speeds
	c. The insufficient speed and power of the basic programmable divider designs
	d. All the above
10	The disadvantage of direct digital synthesizers (DDS) over analog frequency synthesizers is
	a. Its complexity and cost
	b. Its limited maximum output frequency
	c. Its higher phase noise
	d. All the above
11	The G.E. Phoenix radio is an example of
	a. An HF amateur transceiver using AM and SSB modulation modes
	b. A VHF commercial transceiver using the FM modulation mode and a channel guard function
	c. A military transceiver using all modes on HF frequencies
	d. A cellular telephone transceiver
12	The type of radio transmission that uses pseudorandomly switched frequency or time transmissions is known as
	a. Synthesizing
	b. Facsimile
	c. Spread spectrum
	d. Compression
13	The acronym CDMA refers to ________.
	a. Carrier-division multiple-access systems
	b. Capture-division multiple-access systems
	c. Code-division multiple-access systems
	d. Channel-division multiple-access systems
14	A typical problem encountered when troubleshooting a frequency synthesizer is
	a. A small frequency error
	b. A large frequency error
	c. No output
	d. All the above
15	A transceiver is
	a. A transmitter that can be tuned to several bands of frequencies
	b. A transmitter that transmits digital data
	c. A receiver that receives digital data
	d. A transmitter and receiver in a single package

Answers:

B

C

A

D

B

D

B

C

D

D

B

C

C

D

D