PinoyBIX Engineering Problem Solving and Reference

Below are the answers key for Frenzel Self-test in Chapter 14: Modern Communications Applications from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. scanning

2. telephone lines

3. C I TT

4. 2300, 1500

5. 2

6. charge coupled device

7. 3

8. handshaking

9. thermal

10. 9600

11. 200

12.PSK , Q AM

13. half

14. 56K, 400

15. true

16. false

17. true

18. cells

19. mobile telephone switching office

20.more spectrum space at the higher frequencies, frequency reuse of channels.

21. 666

22. true

23. FM

24. 3

25. 825, 845

26. 870, 890

27. 30

28. 45

29. frequency synthesizer

30. 45,82.2, 10.7,0.455

31. change or decrease

32. duplexer or isolator

33. false

34. MT SO

35. transmitter power level received signal level

36. transmit frequency, receive frequency, transmitter power.

37. receive signal strength indicator (RSSI )

38. 82.656

39. logic

40. two

41. control

42. distance or range

43. reflection

44. bearing or azimuth

45. 6.18

46. 3.5

47. 6.1

48. 1.15

49. short

50. microwave

51. true

52. pulse, continuous wave

53. Doppler

54. 589

55. false

56. duplexer

57. magnetron

58. spark gap

59. CRT

60. plan position indicator (PPI )

61. phased array

62. 6 MHz

63. amplitude, frequency

64. 4.5 MHz

65. VHF, UHF

66. luminance Y

67. vidicon, C C D

68. scanning

69. red, green, and blue

70. 525

71. 262 ½

72. 60 (59.94) and 30 (20.97) Hz

73.15,734 Hz (63.6 .s)

74. sync pulses

75. diplexer

76. red, green, blue

77. I, Q

78. balanced modulator, DSB suppressed in-phase and quadrature carrier AM

79. 3.58 MHz

80. phase

81. Y or luminance

82. frequency synthesizer

83. remote control

84. 589.75 MHz

85. 4 MHz

86. 41.25, 45.75 MHz

87. surface acoustic wave (SAW)

88. vestigial sideband AM

89. 4.5 MHz

90. quadrature detector and differential peak detector

91. balanced

92. color burst

93. sync separator

94. 15,734 Hz

95. 59.94 Hz, integrating

96. linear sawtooth

97. yoke

98. cathode, electron gun

99. magnetic fields, yoke coils

100. three

101. convergence

102. horizontal sweep output

103. fly back

104. head end

105. trunk, feeder

106. drops, 75

107. mixer

108. amplifiers

109. mixer, frequency synthesizer channel selector

110. 3, 4, antenna jack

111. less noise and signal attenuation for a better picture, greater reliability of reception, premium cable programming, and no need for an antenna

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 13: Fiber-Optics Communications from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. light

2. voice, video, computer data

3. telephone systems

4. glass, plastic

5. wide bandwidth

6. false

7. true

8. brittleness, difficult to work with

9. LEDs, semiconductor lasers

10. binary or digital pulses

11. photocell or light detector

12. repeaters

13. electromagnetic

14. pipe

15. b (Straight line)

16. micrometers (microns), nanometers

17. a (Red)

18. one-millionth, meter

19. 400, 700

20. b (More than 700 nm)

21. visible, infrared, ultraviolet

22. 300,000,000; 186,000

23. true

24. index, refraction

25. reflection, mirror

26. refraction

27. 30

28. critical

29. reflection

30. index, refraction

31. b (Glass)

32. cladding

33. glass, plastic

34. a (Core)

35. multimode step-index, single-mode step-index, multimode graded-index

36. modal dispersion

37. multimode step-index,

38. multimode graded-index, single-mode step-index

39. b (Decrease)

40. index, refraction

41. c (2 to 15 m)

42. protective coating

43. Kevlar

44. 2, 6, 12, 18, 24

45. attenuation

46. dispersion, absorption, scattering

47. decibels, kilometer

48. 31

49. false

50. a (40 ft.)

51. 76

52. true

53. connectors

54. LED. laser

55. 1.3

56. false

57. gallium arsenide

58. monochromatic

59. coherence

60. laser

61. resonant cavity

62. forward

63. ILD

64. ILD

65. reverse

66. leakage

67. avalanche photodiode

68. amplifier, comparator-or shaper

69. 30

70. 6.17. 18.5 (10 and 30 km)

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 12: Data Communications from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. binary or digital

2. true

3. telegraph

4. continuous wave (CW)

5. dots, dashes

6. K = _._; 8= _ _ _.. ; , = _ _.._ _

7. baudot

8. teletype

9. M

10. ASCII

11. EBCDIC

12. B = 1000010; 3 = 0110011; ? = 0111111

13. 0000111

14. serial, parallel

15. false

16. shift register

17. start, stop

18. bits per second (bits/s)

19. baud rate

20. true

21. false

22. blocks

23. space, mark

24. information theory

25. bandwidth, time

26. 10,000

27. 60,000

28. true

29. less

30. 50

31. 100

32. modulator, demodulator

33. analog, digital (or binary)

34. telephone network

35. computers

36. frequency-shift keying

37. frequencies

38. mark (1), space (0)

39. 1070, 1270, 2025, 2225

40. universal asynchronous receiver transmitter (UART)

41. phase-shift keying

42. 0, 180

43. balanced modulator

44. balanced modulator

45. carrier recovery

46. differential

47. XNOR

48. four

49. 2 bits

50. four

51. bit splitter (or shift register)

52. 2-t0-4 level converter

53. amplitude, PSK

54. true

55. false

56. true

57. false

58. true

59. protocols

60. redundancy, special error-checking codes, parity, block check code, cyclical redundancy check

61. handshaking

62. Xmodem

63. block

64. asynchronous

65. SYN or sync

66. header

67. STX, ETX or ETB

68. redundancy

69. ARQ exact-count

70. noise

71. bit error rate

72. parity

73. block check character

74.

• a. 1
• b. 0
• c. 1
• d. 1

75. vertical redundancy check

76. exclusive OR

77. block check character

78. longitudinal redundancy check

79. cyclical redundancy check

80. shift register

81. true

82. wide area network

83. true

84. local area networks

85. private branch exchange

86. false

87. star, ring, bus

88. star

89. star

90. mainframe (or mini)

91. ring

92. nodes

93. bus

94. bus

95. ring

96. gateway

97. bridge

98. twisted pair, coax, fiber-optic cable

99. tree

100. noise susceptibility, short distances, low data rates

101. coax

102.fiber-optic cable

103. coax

104. 1, 10,50

105. baseband

106. baseband

107. broadband

108. modem

109. modulation, multiplexing

110. frequency hopping, direct sequence

111. frequency synthesizer

112. pseudorandom noise code generator

113. false

114. noise

115. PSN code

116. dwell time

117. X-OR

118. true

119. PSK

120. synchronism

121. correlation

122. security, jam-proof

123. shift register

124. 902- to 928-, 2400- to 2483-, 5725- to 5850-MHz

125. wireless LANs, wireless computer modems

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 11: Satellite Communications from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. centripetal force, gravitational pull

2. posigrade

3. ellipse

4. geocenter

5. period

6. 0,90

7. 5

8. geosynchronous or geostationary

9. attitude

10. spin, three-axis stabilization

11. yaw, pitch, roll

12. subsatellite point

13. latitude, longitude

14. azimuth, elevation

15. apogee kick motor

16. communications

17. relay station

18. earth station

19. down link

20. transponder

21. microwave

22. C

23. X

24. 10.95, 14.5

25. 500

26. 12,36

27. frequency reuse

28. spatial isolation

29. voice, video, computer or digital data

30. low-noise amplifier

31. signal amplification, frequency translation, power amplification

32. mixer

33. TWT

34. double-conversion

35. regenerative

36. bandpass filter

37. broadband, multichannel

38. solar panels

39. batteries

40. monitor, control

41. jet thrusters

42. baseband

43. down converter

44. 70

45. demodulation, demultiplexing

46. modulation, multiplexing

47. FM, QPSK

48. up converter

49. frequency synthesizers

50. transistor, TWT, klystron

51. backup power or uninterruptible power supply

52. false

53. communications

54. film cameras, TV cameras, infrared sensors, radar

55. Global Positioning System (GPS), navigation

56. weather forecasting, spying, earth resources, monitoring

57. TV reception

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 10: Microwave Techniques from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. 1

2. bandwidth or spectrum

3. more difficult to analyze; different measurement techniques; resistors, capacitors, and inductors act

like LCR circuits; conventional semiconductors do not work owing to internal capacitances and long

transit time; special, expensive vacuum tubes are used for power amplification; line-of-sight

transmission differences; excessive signal reflection and absorption

4. telephone, radar

5. television signal relay, space communications, radio telescopes, microwave heating

6. Federal Communications Commission

7. improved receiver selectivity, SSB, multiplexing, reduced FM deviation

8. internal capacitance, long transit time

9. LCR

10. 36, 3.6

11. true

12. attenuation

13. 6

14. waveguide

15. microstrip, stripline

16. probe, loop

17. high-pass

18. 4.921

19. (a) true, (b) false

20. H, E

21.TEO,1

22. transverse magnetic

23. cavity resonator

24. parallel resonant

25. tuned circuits, filters

26. resonant frequency

27. high capacitance, high inductance, long transit time

28. P-type silicon, tungsten whisker

29. Schottky barrier, or hot carrier

30. mixer

31. varactor

32. varactor, snap-off or step-recovery diode

33. Gunn

34. IMPATT, TRAPATT, tunnel

35. negative resistance

36. reverse

37. forward

38. true

39. false

40. amplifier

41. cavity resonators

42. velocity

43. buncher, catcher

44. reflex

45. Gunn diodes, TWTs

46. permanent magnet

47. radar, microwave ovens

48. amplifier

49. helix

50. bandwidth

51. horn

52. increase, decrease

53. 11.8

54. 10, 60

55. 37.5, 13.3

56. wide

57. parabola

58. focal point

59. horn

60. 55.39, 0.242

61. increase, decrease

62. Cassegrain

63. simplicity, low cost

64. 12, 20

65. 12, 45

66. circularly

67. right-hand circular polarization

68. bicone

69. true

70. false

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 9: Antennas and Transmission Lines from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. balanced, coax

2. unbalanced

3. wavelength

4. 0.667

5. 1.475

6. characteristic or surge impedance

7. low-pass filter, capacitors, inductors

8. 75.23

9. 6.25

10. 52

11. constant or fiat

12. standing waves

13. reflected

14. standing waves

15. 1.44

16. 1

17. open, shorted

18. reflection coefficient

19. 1.67,0.25

20. 7

21. 1, infinity

22. tuned or resonant circuits

23. 6.3 [0.07(90)=6.3] (See Fig. 9-12.)

24. high or infinite

25. open, shorted

26. inductors, capacitors

27. series

28. 2.788

29. electric, magnetic

30. electric field

31. transmission or feed line

32. vertically

33. dipole or doublet

34. 3.12

35. 73

36. figure eight

37. beam width

38. omni directional

39. ground plane

40. 3.16

41. earth ground, radials

42. circle

43. 36.5

44. bidirectional

45. one

46. gain

47. elements

48. parasitic, driven

49. director, reflector, driven element

50. director, reflector

51. director

52. 20, 40

53. 2.1

54. collinear, end-fire, broadside

55. true

56. log-periodic

57. antenna tuner

58. balun

59.Q section, matching stub

60. 60.4:1

61. 9.39

62. ground or surface wave, sky wave, direct or space wave

63. ground, surface

64. sky

65. 65. direct or space

66. 3

67. ionosphere

68. F

69. refracted or bent

70. true

71. false

72. 3, 30

73. multiple hop

74. straight line

75. repeaters

76. transmitter, receiver

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 8: Multiplexing from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. c. (Multiplexing uses a single channel to transmit multiple signals.)

2. telephone, telemetry

3. economy

4. demultiplexer

5. time division, frequency division

6. bandwidth

7. subcarriers

8. linear mixer

9. modulate

10. frequency

11. amplifying, filtering

12. subcarrier oscillator or VCO

13. bandpass filter

14. PLL

15. SSB

16.L + R

17.L + R. L - R. 19-kHz pilot, SCA

18. DSB

19. frequency

20. time slots or intervals.

21. pulse-amplitude modulation

22. 14

23. FET or MOSFET

24. clock recovery circuit

25. sync pulse

26. frame

27. low-pass filter

28. switch

29. gate

30. FM

31. phase-locked loop

32. binary codes

33. AID converter

34. 8

35. 8

36. T-1

37. companding

38. codec

39. noise

40. 24, 1.544

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 7: Communications Receivers from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. selectivity

2. increase

3. narrow

4. true (resonant step-up)

5. increase(narrower bandwidth)

6. sidebands

7. 5

8. 0.53 MHz or 530 kHz (fr = 10.6 MHz, XL = 200 , Q = 20)

9. 9.95, 10.05

10. 1333.3

11. decreased

12. 2.4

13. sensitivity

14. tuned radio frequency

15. superheterodyne

16. intermediate frequency

17. local oscillator

18. IF amplifier

19. automatic gain control

20. signal or input, local oscillator

21. IF amplifier

22. c (low)

23. Image

24. 3.5

25. selectivity

26. 28

27. true

28. mixer

29. Intermediate frequency

30. 9,600

31. industrial, atmospheric, and space

32. thermal agitation, shot noise, transit-time noise

33. extraterrestrial or space

34. lightning

35. automobiles, motors, generators, fluorescent lights

36. thermal agitation

37. decibels

38. high

39. increase

40. white, Johnson

41. decrease

42. 1.36

43. shot, transit-time

44. false

45. true

46. noise figure

47. microwave

48. 48.464

49. 49. distortion

50. 50. high

51. RF amplifier, mixer

52. true

53. gain, selectivity, noise

54. MESFET or GASFET, gallium arsenide

55. IF

56. tuned circuits

57. mutual inductance

58. under, over, optimum, critical

59. limiter

60. cutoff, saturation

61. collector current

62. 100

63. automatic gain control

64. IF

65. rectifier, IF amplifier or detector

66. decrease

67. increase

68. constant-current source

69. control gate

70. automatic volume control

71. diode detector

72. reduced

73. local oscillator

74. demodulator

75. voltage-variable capacitor

76. squelch

77. audio, noise

78. tone, squelch

79. SSB, CW

80. the ceramic filter FIL1

81.As the pot arm voltage goes more positive, the reverse bias across D1 increases, thus decreasing its capacitance and the overall capacitance of D1 in series with C14; this in turn increases the local oscillator frequency.

82. volume R2 and squelch R3

83. U2, the MC1350 IF amplifier IC

84. The squelch is signal derived

85. With no BFO, the receiver cannot receive CW or SSB.

86. The gain increases.

87. pin 5 of the U3-b op amp

88.10.7 MHz injected to the ceramic filter FIL1

89. U2, the MC1350 IC, would lose supply voltage at pin 2.

90. A digital counter could be connected to monitor the local oscillator output signal at pin 6 or 7 of the NE602 mixer IC. This would read the local oscillator frequency, which is 10.7 MHz higher than the actual input signal frequency. Therefore, the counter would have to be preset to a value that is 10.7 MHz less than zero count. In this way, the IF value would effectively be subtracted from the input count to read the correct frequency. Assume that the counter is set up to count four digits, 000.0. The counter is preset to 100.0 - 10.7= 89.3, and the input signal frequency is 118 MHz. The local oscillator is tuned to 118 + 10.7 = 128.7 MHz. The counter counts 10.7 to reach 000.0 and then counts 118 more to display a final value of 118.0.

91. power supply

92. crystal filter, local oscillators

93. frequency synthesizer

94. phase-locked loop

95. frequency division ratio

96. 2.86, 10

97. mixer

98. LO for first mixer, LO for second mixer, transmitter

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 6: Radio Transmitters from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. oscillator

2. continuous-wave, CW

3. crystal oscillator

4. buffer

5. drivers

6. final

7. speech-processing

8. frequency multipliers

9. mixer

10. linear

11. class C

12. AM, SSB

13. class C

14. A, B, AB

15. 27

16. 360

17. base-collector capacitance

18. parasitic oscillation

19. neutralization

20. true

21. bridge

22. true

23. push-pull

24. 90, 150

25. pulses

26. tuned or resonant circuit

27. 60, 85

28. harmonics

29. frequency multipliers

30. 180 [2(3)(4)(5) = 120; 120(1.5)=180 MHz]

31. 50.4 [28(1.8) = 50.4 W]

32. equals

33. L network

34.pi ( ), T

35. low-pass

36. Q

37. true

38. L = 108 nH, C = 558 pF

39. L = 106 nH, C1 = 13.5 pF, C2= 34 pF

40. 450

41. 2:1

42. autotransformer

43. toroid

44. balun

45. broadband

46. clipping, compression

47. prevent over modulation and distortion, eliminate out-of-band operation

48. clipper

49. smooth out distortion caused by clipping, restrict signal bandwidth

50. splatter

51. gain

52. power

53. rectifying, filtering

54. collector current

55. automatic gain control

56. more

57. true

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 5: Frequency Modulation Circuits from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. b (decrease)

2. b (decrease)

3. b (decrease)

4. a (increase)

5. a (increase)

6. varactor diode (or varicap)

7. 1,200

8. frequency stability

9. voltage-controlled oscillator

10. VXO

11. frequency multiplier

12. increase

13. resistance, capacitance

14. true

15. false

16. false

17. true

18. indirect

19. true

20. 0, 90

21. resistance, capacitance

22. parallel resonant (or tuned)

23. varactor

24.R04

25. lead

26. decrease

27.C1, C2, Q1 and C1, R1, Q1

28. frequency multiplier

29. phase shift

30. one-shot or monostable multivibrator

31. increase

32. 90

33. lead

34. differential amplifier

35. phase shift

36. low-pass filter

37. peak detector

38.C1, C2, L1

39. phase detector, VCO, low-pass filter

40. phase detector, frequency, phase

41. VCO

42. error

43. lock

44. free-running

45. capture

46. band pass filter

47. modulating signal or information signal

48. FM input

49. true

50. false

51. false

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 4: Frequency Modulation from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. angle

2. true

3. deviation

4. amplitude

5. increases, decreases (the reverse could also be true)

6. phase shift

7. frequency shift or deviation

8. changing or varying

9. amplitude, frequency

10. a

11. b

12. indirect FM

13. true

14. modulation index

15.3 (m = 10/33 = 3)

16. 5

17. 995.5, 1004.5 [3(1.5) = 4.5 KHz; 1000 4.5 = 995.5 and 1004.5 kHz]

18. 0.28

19. Bessel functions

20. 60 [2(5)(6)= 60 kHz]

21. 75 [(3.75/5)100 = 75%]

22. phase inversion or 180° shift

23. false

24. BW = 40 kHz; BW = 28 kHz using Carson's rule; Carson's rule gives narrower bandwidths because sidebands of less than 2 percent amplitude are not considered

25. noise

26. a

27. limiter (or clipper)

28. capture effect

29. C

30. spectrum space

31. false

32. high

33. pre-emphasis

34. high-pass filter

35. de-emphasis

36. 75

37. 2122

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 3: Amplitude Modulation Circuits from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. a

2. b

3. c

4. gain, attenuation

5. square law

6. diode

7. tuned circuit

8. variable resistor

9. gain

10. increase, decrease, increase

11. resistor

12. 100 MHz

13. attenuator

14. low

15. linear amplifier

16. C

17. collector

18. supply voltage

19. 2.5

20. 12

21. driver

22. demodulator

23. diode detector

24.C1

25. ripple, distortion

26. envelope

27. smaller filter capacitor, less ripple and distortion

28. true

29. c

30. d

31. b

32. lattice modulator or diode ring

33. switches

34. 1897.4, 1902.6

35.Q7, Q8

36. switches

37. true

38. filter

39. selectivity

40. 2.9985

41. crystals

42. Use one filter for each sideband; select the carrier frequency so that the desired sideband is in the filter passband.

43.tune, resonant, or LC

44. 1.8 (3.0012- 3.0 = 0.0012 MHz = 1.2 kHz; 1.2 x 1.5 = 1.8 kHz)

45. vibrate or resonate

46. crystal

47. 200 to 500

48. phase shift

49. mixer or balanced modulator

50. product detector

51. b

52. b

53. b

54. heterodyning

55. frequency conversion or translation

56. f₁ ,f₂, f₁ + f₂, f₁ - f₂

57. diode

58. doubly balanced mixer, GaAsFET

59. gain

60. 455 (1845 – 1390 = 455)

61. converter

62. cross-connected differential amplifier

63. local oscillator

64. 21.3 or 32.3 MHz

65. true

66. true

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 2: Amplitude Modulation and Single-Sideband Modulation from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. translated

2. varies, carrier

3. modulator, carrier, modulating signal

4. amplitude

5. false

6. envelope, modulating signal

7. time-domain

8. Vc = sin 2 fct

9. true

10. c

11. c

12. a

13. d

14. modulating signal, carrier

15. 43.4

16. 100

17. 17.34 V

18. 66.67

19. sidebands

20. 635, 625

21. 10

22. time, oscilloscope

23. frequency, spectrum analyzer

24. sidebands

25. d

26. Carrier, upper sideband, lower sideband

27. b

28. b

29. antenna

30. carrier, sideband

31. 0.45

32. 5.06

33. 63.25

34. 236 W

35. 400 W, 89.44 percent

36. 1.8 amperes

37. DSB

38. false

39. b

40. a

41. less spectrum space, more power in the sidebands with greater efficiency, less noise, little or no fading

42. telephone systems, two-way radio

43. c

44. true

45. vestigial sideband

46. 863.7

47. 345

48. 3-, 4-W

49. frequency conversion

50. mixer, converter

51. 4.155 MHz, 7.855 MHz, 455 kHz, 3.7 MHz

52. 117.8 MHz

53. filter or tuned circuit

54. false

55. true

56. heterodyning

Complete List of Self-test and Reviewers in Communications Electronics

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Below are the answers key for Frenzel Self-test in Chapter 1: Introduction to Electronic Communications from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

1. computers, communications, control ; computers

2. exchanging information

3. oral, written

4. distance, language

5. late nineteenth century

6. transmitter, receiver, channel or medium

7. wire, radio, fiber-optic cable

8. transmitter

9. receiver

10. noise, communications channel

11. degrades, attenuates

12. the atmosphere, manufactured equipment, thermal agitation in components

13. simplex, radio and TV broadcasting

14. full duplex, telephone communications

15. half duplex

16. analog

17. digital

18. analog-to-digital converter

19. base band

20. Modulation. base band, carrier

21. demodulation or detection

22. multiplexing

23. facsimile, teletext

24. garage door opener

25. paging

26. telemetry

27. radio waves

28. microwave relay, satellites, cordless phones, cellular phones

29. reflected

30. sonar (active)

31. active, passive

32. amateur or "ham" radio

33. modems

34. local area networks

35. electromagnetic waves or radio-frequency (RF) waves

36. electric, magnetic

37. 16.67 (300/18= 16.67)

38. 50, 60, ELF

39. a. c

40. 20, 20,000

41. 300, 3000

42. false

43. MF

44. short waves

45. VHF

46. land mobile, cellular telephones, military, radar and navigation, amateur radio

47. 1000

48. microwaves

49. radar, satellite

50. millimeter

51. 1 / 1,000,000

52. heat

53. 0.7, 10

54. 1 / 10.000

55. 4000,8000

56. fiber-optic cables, free space

57. bandwidth

58. sidebands

59. 125 (1.175 - 1.050 = 0.125 MHz = 125 kHz)

60. higher

61. lower

62. spectrum space

63. Communications Act of 1934

64. Federal Communications Commission

65. National Telecommunications and Information Administration

66. International Telecommunications Union

Complete List of Self-test and Reviewers in Communications Electronics

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