Electronic Systems Electronic Systems and Technologyand Technology

Compiled by: Aaron AgootCompiled by: Aaron Agoot

BSECEBSECE

CHAPTER 1: CHAPTER 1: INTRODUCTION TO INTRODUCTION TO COMMUNICATION SYSTEMCOMMUNICATION SYSTEM

1. In a communication system, 1. In a communication system, noise is most likely to affect the noise is most likely to affect the signalsignal

a. at the transmittera. at the transmitter

b. in the channelb. in the channel

c. in the information sourcec. in the information source

d. at the destinationd. at the destination

1. In a communication system, 1. In a communication system, noise is most likely to affect the noise is most likely to affect the signalsignal

a. at the transmittera. at the transmitter

b. in the channelb. in the channel

c. in the information sourcec. in the information source

d. at the destinationd. at the destination

2. Indicate the false statement. Fourier 2. Indicate the false statement. Fourier analysis shows that the saw tooth wave analysis shows that the saw tooth wave consist ofconsist of

a. fundamental and sub harmonic sine wavesa. fundamental and sub harmonic sine wavesb. a fundamental sine wave and an infinite b. a fundamental sine wave and an infinite

number of harmonicsnumber of harmonicsc. fundamental and harmonic sine waves c. fundamental and harmonic sine waves

whose amplitude decreases with the whose amplitude decreases with the harmonic numberharmonic number

d. sinusoidal voltages, some of which are d. sinusoidal voltages, some of which are small enough to ignore in practicesmall enough to ignore in practice

2. Indicate the false statement. Fourier 2. Indicate the false statement. Fourier analysis shows that the saw tooth wave analysis shows that the saw tooth wave consist ofconsist of

a. fundamental and sub harmonic sine wavesa. fundamental and sub harmonic sine wavesb. a fundamental sine wave and an infinite b. a fundamental sine wave and an infinite

number of harmonicsnumber of harmonicsc. fundamental and harmonic sine waves c. fundamental and harmonic sine waves

whose amplitude decreases with the whose amplitude decreases with the harmonic numberharmonic number

d. sinusoidal voltages, some of which are d. sinusoidal voltages, some of which are small enough to ignore in practicesmall enough to ignore in practice

3. Indicate the false statement. 3. Indicate the false statement. Modulation is used toModulation is used to

a. reduce the bandwidth useda. reduce the bandwidth used

b. separate the differing transmissionsb. separate the differing transmissions

c. ensure that intelligence may be c. ensure that intelligence may be transmitted over long distancestransmitted over long distances

d. allow the use of practicable d. allow the use of practicable antennasantennas

3. Indicate the false statement. 3. Indicate the false statement. Modulation is used toModulation is used to

a. reduce the bandwidth useda. reduce the bandwidth used

b. separate the differing transmissionsb. separate the differing transmissions

c. ensure that intelligence may be c. ensure that intelligence may be transmitted over long distancestransmitted over long distances

d. allow the use of practicable d. allow the use of practicable antennasantennas

4. Indicate the false statement. From 4. Indicate the false statement. From the transmitter the signal the transmitter the signal deterioration because of noise is deterioration because of noise is usuallyusually

a. unwanted energya. unwanted energy

b. predictable in characterb. predictable in character

c. present in the transmitterc. present in the transmitter

d. due to any caused. due to any cause

4. Indicate the false statement. From 4. Indicate the false statement. From the transmitter the signal the transmitter the signal deterioration because of noise is deterioration because of noise is usuallyusually

a. unwanted energya. unwanted energy

b. predictable in characterb. predictable in character

c. present in the transmitterc. present in the transmitter

d. due to any caused. due to any cause

5. Indicate the true statement. 5. Indicate the true statement. Most receivers conforms to theMost receivers conforms to the

a. amplitude-modulated groupa. amplitude-modulated group

b. frequency-modulated groupb. frequency-modulated group

c. superheterodyne groupc. superheterodyne group

d. tuned radio frequency receiver d. tuned radio frequency receiver groupgroup

5. Indicate the true statement. 5. Indicate the true statement. Most receivers conforms to theMost receivers conforms to the

a. amplitude-modulated groupa. amplitude-modulated group

b. frequency-modulated groupb. frequency-modulated group

c. superheterodyne groupc. superheterodyne group

d. tuned radio frequency receiver d. tuned radio frequency receiver groupgroup

6. Indicate the false statement. The need for 6. Indicate the false statement. The need for modulation can best be exemplified by the modulation can best be exemplified by the following.following.

a. antenna lengths will be approximately a. antenna lengths will be approximately /4 /4 longlong

b. an antenna in the standard broadcast AM b. an antenna in the standard broadcast AM band is 16,000 ftband is 16,000 ft

c. all sound is concentrated from 20 Hz to 20 c. all sound is concentrated from 20 Hz to 20 kHzkHz

d. a message is composed of unpredictable d. a message is composed of unpredictable variations in both amplitude and frequencyvariations in both amplitude and frequency

6. Indicate the false statement. The need for 6. Indicate the false statement. The need for modulation can best be exemplified by the modulation can best be exemplified by the following.following.

a. antenna lengths will be approximately a. antenna lengths will be approximately /4 /4 longlong

b. an antenna in the standard broadcast AM b. an antenna in the standard broadcast AM band is 16,000 ftband is 16,000 ft

c. all sound is concentrated from 20 Hz to 20 c. all sound is concentrated from 20 Hz to 20 kHzkHz

d. a message is composed of unpredictable d. a message is composed of unpredictable variations in both amplitude and frequencyvariations in both amplitude and frequency

7. Indicate the true statement. The 7. Indicate the true statement. The process of sending and receiving process of sending and receiving started as early asstarted as early as

a. the middle 1930sa. the middle 1930sb. 1850b. 1850c. the beginning of the twentieth c. the beginning of the twentieth

centurycenturyd. the 1840sd. the 1840s

7. Indicate the true statement. The 7. Indicate the true statement. The process of sending and receiving process of sending and receiving started as early asstarted as early as

a. the middle 1930sa. the middle 1930sb. 1850b. 1850c. the beginning of the twentieth c. the beginning of the twentieth

centurycenturyd. the 1840sd. the 1840s

8. Which of the steps is not 8. Which of the steps is not included in the process of included in the process of reception?reception?

a. decodinga. decoding

b. encodingb. encoding

c. storagec. storage

d. interpretationd. interpretation

8. Which of the steps is not 8. Which of the steps is not included in the process of included in the process of reception?reception?

a. decodinga. decoding

b. encodingb. encoding

c. storagec. storage

d. interpretationd. interpretation

9. The acoustic channel is used for 9. The acoustic channel is used for which of the following?which of the following?

a. UHF communicationsa. UHF communications

b. single-sideband communicationb. single-sideband communication

c. television communicationsc. television communications

d. person-to-person voice d. person-to-person voice communications.communications.

9. The acoustic channel is used for 9. The acoustic channel is used for which of the following?which of the following?

a. UHF communicationsa. UHF communications

b. single-sideband communicationb. single-sideband communication

c. television communicationsc. television communications

d. person-to-person voice d. person-to-person voice communications.communications.

10. Amplitude modulation is the 10. Amplitude modulation is the process ofprocess of

a. superimposing a low frequency a. superimposing a low frequency on a high frequencyon a high frequency

b. superimposing a high frequency b. superimposing a high frequency on a low frequencyon a low frequency

c. carrier interruptionc. carrier interruptiond. frequency shift and phase shiftd. frequency shift and phase shift

10. Amplitude modulation is the 10. Amplitude modulation is the process ofprocess of

a. superimposing a low frequency a. superimposing a low frequency on a high frequencyon a high frequency

b. superimposing a high frequency b. superimposing a high frequency on a low frequencyon a low frequency

c. carrier interruptionc. carrier interruptiond. frequency shift and phase shiftd. frequency shift and phase shift

CHAPTER 2: NOISECHAPTER 2: NOISE

1. One of the following types of noise 1. One of the following types of noise becomes a great importance at becomes a great importance at high frequencies. Is thehigh frequencies. Is the

a. shot noisea. shot noise

b. random noiseb. random noise

c. impulse noisec. impulse noise

d. transit-time noised. transit-time noise

1. One of the following types of noise 1. One of the following types of noise becomes a great importance at becomes a great importance at high frequencies. Is thehigh frequencies. Is the

a. shot noisea. shot noise

b. random noiseb. random noise

c. impulse noisec. impulse noise

d. transit-time noised. transit-time noise

2. Indicate the false statement2. Indicate the false statement

a. HF mixers are generally noisier than a. HF mixers are generally noisier than HF amplifiersHF amplifiers

b. Impulse noised voltage is independent b. Impulse noised voltage is independent of the bandwidthof the bandwidth

c. Thermal noise is independent of the c. Thermal noise is independent of the frequency at which it is measuredfrequency at which it is measured

d. Industrial noise is usually of the d. Industrial noise is usually of the impulse typeimpulse type

2. Indicate the false statement2. Indicate the false statement

a. HF mixers are generally noisier than a. HF mixers are generally noisier than HF amplifiersHF amplifiers

b. Impulse noised voltage is independent b. Impulse noised voltage is independent of the bandwidthof the bandwidth

c. Thermal noise is independent of the c. Thermal noise is independent of the frequency at which it is measuredfrequency at which it is measured

d. Industrial noise is usually of the d. Industrial noise is usually of the impulse typeimpulse type

3. The value of the resistor creating 3. The value of the resistor creating thermal noise is doubled. The noise thermal noise is doubled. The noise power generated is thereforepower generated is therefore

a. halveda. halved

b. quadrupledb. quadrupled

c. doublec. double

d. unchangedd. unchanged

3. The value of the resistor creating 3. The value of the resistor creating thermal noise is doubled. The noise thermal noise is doubled. The noise power generated is thereforepower generated is therefore

a. halveda. halved

b. quadrupledb. quadrupled

c. doublec. double

d. unchangedd. unchanged

4. One of the following is not useful 4. One of the following is not useful quantity for comparing the noise quantity for comparing the noise performance of the receiverperformance of the receiver

a. Input noise voltagea. Input noise voltage

b. Equivalent noise resistanceb. Equivalent noise resistance

c. Noise temperaturec. Noise temperature

d. Noise figured. Noise figure

4. One of the following is not useful 4. One of the following is not useful quantity for comparing the noise quantity for comparing the noise performance of the receiverperformance of the receiver

a. Input noise voltagea. Input noise voltage

b. Equivalent noise resistanceb. Equivalent noise resistance

c. Noise temperaturec. Noise temperature

d. Noise figured. Noise figure

5. Indicate the noise whose source 5. Indicate the noise whose source is in a category different from is in a category different from that of the other three.that of the other three.

a. solar noisea. solar noise

b. cosmic noiseb. cosmic noise

c. atmospheric noisec. atmospheric noise

d. galactic noised. galactic noise

5. Indicate the noise whose source 5. Indicate the noise whose source is in a category different from is in a category different from that of the other three.that of the other three.

a. solar noisea. solar noise

b. cosmic noiseb. cosmic noise

c. atmospheric noisec. atmospheric noise

d. galactic noised. galactic noise

6. Indicate the false statement. The 6. Indicate the false statement. The square of the thermal noise voltage square of the thermal noise voltage generated by a resistor is proportional generated by a resistor is proportional toto

a. its resistancea. its resistance

b. its temperatureb. its temperature

c. Boltzmann’s Constantc. Boltzmann’s Constant

d. the bandwidth over which it is d. the bandwidth over which it is measuredmeasured

6. Indicate the false statement. The 6. Indicate the false statement. The square of the thermal noise voltage square of the thermal noise voltage generated by a resistor is proportional generated by a resistor is proportional toto

a. its resistancea. its resistance

b. its temperatureb. its temperature

c. Boltzmann’s Constantc. Boltzmann’s Constant

d. the bandwidth over which it is d. the bandwidth over which it is measuredmeasured

7. Which of the broad classifications 7. Which of the broad classifications of noise are most difficult to treat?of noise are most difficult to treat?

a. noise generated in the receivera. noise generated in the receiver

b. noise generated in the transmitterb. noise generated in the transmitter

c. externally generated noisec. externally generated noise

d. internally generated noised. internally generated noise

7. Which of the broad classifications 7. Which of the broad classifications of noise are most difficult to treat?of noise are most difficult to treat?

a. noise generated in the receivera. noise generated in the receiver

b. noise generated in the transmitterb. noise generated in the transmitter

c. externally generated noisec. externally generated noise

d. internally generated noised. internally generated noise

8. Space noise generally covers a 8. Space noise generally covers a wide frequency spectrum, but the wide frequency spectrum, but the strongest interference occursstrongest interference occurs

a. between 8MHz and 1.43 GHza. between 8MHz and 1.43 GHz

b. below 20 MHzb. below 20 MHz

c. between 20 to 120 MHzc. between 20 to 120 MHz

d. above 1.5 GHzd. above 1.5 GHz

8. Space noise generally covers a 8. Space noise generally covers a wide frequency spectrum, but the wide frequency spectrum, but the strongest interference occursstrongest interference occurs

a. between 8MHz and 1.43 GHza. between 8MHz and 1.43 GHz

b. below 20 MHzb. below 20 MHz

c. between 20 to 120 MHzc. between 20 to 120 MHz

d. above 1.5 GHzd. above 1.5 GHz

9. When dealing with random noise 9. When dealing with random noise calculations it must be remembered calculations it must be remembered thatthat

a. all calculations are based on peak to a. all calculations are based on peak to peak valuespeak values

b. calculations are based on peak valuesb. calculations are based on peak values

c. calculations are based on average c. calculations are based on average valuesvalues

d. calculations are based on RMS valuesd. calculations are based on RMS values

9. When dealing with random noise 9. When dealing with random noise calculations it must be remembered calculations it must be remembered thatthat

a. all calculations are based on peak to a. all calculations are based on peak to peak valuespeak values

b. calculations are based on peak valuesb. calculations are based on peak values

c. calculations are based on average c. calculations are based on average valuesvalues

d. calculations are based on RMS valuesd. calculations are based on RMS values

10. Which of the following is the 10. Which of the following is the most reliable measurement for most reliable measurement for comparing amplifier noise comparing amplifier noise characteristics?characteristics?

a. signal-to-noise ratioa. signal-to-noise ratio

b. noise factorb. noise factor

c. shot noisec. shot noise

d. thermal noise agitationd. thermal noise agitation

10. Which of the following is the 10. Which of the following is the most reliable measurement for most reliable measurement for comparing amplifier noise comparing amplifier noise characteristics?characteristics?

a. signal-to-noise ratioa. signal-to-noise ratio

b. noise factorb. noise factor

c. shot noisec. shot noise

d. thermal noise agitationd. thermal noise agitation

11. Which of the following statements is 11. Which of the following statements is true?true?

a. Random noise power is inversely a. Random noise power is inversely proportional to bandwidthproportional to bandwidth

b. Flicker is sometimes called b. Flicker is sometimes called demodulation noisedemodulation noise

c. Noise in mixers is caused by c. Noise in mixers is caused by inadequate image frequency rejectioninadequate image frequency rejection

d. A random voltage across a resistance d. A random voltage across a resistance cannot be calculatedcannot be calculated

11. Which of the following statements is 11. Which of the following statements is true?true?

a. Random noise power is inversely a. Random noise power is inversely proportional to bandwidthproportional to bandwidth

b. Flicker is sometimes called b. Flicker is sometimes called demodulation noisedemodulation noise

c. Noise in mixers is caused by c. Noise in mixers is caused by inadequate image frequency rejectioninadequate image frequency rejection

d. A random voltage across a resistance d. A random voltage across a resistance cannot be calculatedcannot be calculated

CHAPTER 3: CHAPTER 3: AMPLITUDE AMPLITUDE MODULATIONMODULATION

1. If the plate supply voltage for a 1. If the plate supply voltage for a plate modulated class C amplifier is plate modulated class C amplifier is V, the maximum plate-cathode V, the maximum plate-cathode voltage could be almost as high asvoltage could be almost as high as

a. 4Va. 4Vb. 3Vb. 3Vc. 2Vc. 2Vd. Vd. V

1. If the plate supply voltage for a 1. If the plate supply voltage for a plate modulated class C amplifier is plate modulated class C amplifier is V, the maximum plate-cathode V, the maximum plate-cathode voltage could be almost as high asvoltage could be almost as high as

a. 4Va. 4Vb. 3Vb. 3Vc. 2Vc. 2Vd. Vd. V

2. In a low-level AM system, 2. In a low-level AM system, amplifiers following the amplifiers following the modulated stage must bemodulated stage must be

a. linear devicesa. linear devices

b. harmonic devicesb. harmonic devices

c. class C amplifiersc. class C amplifiers

d. non linear devicesd. non linear devices

2. In a low-level AM system, 2. In a low-level AM system, amplifiers following the amplifiers following the modulated stage must bemodulated stage must be

a. linear devicesa. linear devices

b. harmonic devicesb. harmonic devices

c. class C amplifiersc. class C amplifiers

d. non linear devicesd. non linear devices

3. If the carrier of a 100 percent 3. If the carrier of a 100 percent modulated AM wave is suppressed, modulated AM wave is suppressed, the percentage power saving will the percentage power saving will bebe

a. 50a. 50

b. 150b. 150

c. 100c. 100

d. 66.66d. 66.66

3. If the carrier of a 100 percent 3. If the carrier of a 100 percent modulated AM wave is suppressed, modulated AM wave is suppressed, the percentage power saving will the percentage power saving will bebe

a. 50a. 50

b. 150b. 150

c. 100c. 100

d. 66.66d. 66.66

4. Leak type bias is used in a plate 4. Leak type bias is used in a plate modulated class C amplifier tomodulated class C amplifier to

a. prevent tuned circuit dampinga. prevent tuned circuit damping

b. prevent excessive grid currentb. prevent excessive grid current

c. prevent over modulationc. prevent over modulation

d. increase the bandwidthd. increase the bandwidth

4. Leak type bias is used in a plate 4. Leak type bias is used in a plate modulated class C amplifier tomodulated class C amplifier to

a. prevent tuned circuit dampinga. prevent tuned circuit damping

b. prevent excessive grid currentb. prevent excessive grid current

c. prevent over modulationc. prevent over modulation

d. increase the bandwidthd. increase the bandwidth

5. The output stage of a television 5. The output stage of a television transmitter is most likely to be atransmitter is most likely to be a

a. plate modulated class C amplifiera. plate modulated class C amplifier

b. grid modulated class C amplifierb. grid modulated class C amplifier

c. screen modulated class C c. screen modulated class C amplifieramplifier

d. grid modulated class A amplifierd. grid modulated class A amplifier

5. The output stage of a television 5. The output stage of a television transmitter is most likely to be atransmitter is most likely to be a

a. plate modulated class C amplifiera. plate modulated class C amplifier

b. grid modulated class C amplifierb. grid modulated class C amplifier

c. screen modulated class C c. screen modulated class C amplifieramplifier

d. grid modulated class A amplifierd. grid modulated class A amplifier

6. The modulation index of an AM is 6. The modulation index of an AM is changed from 0 to 1. The changed from 0 to 1. The transmitted power istransmitted power is

a. unchangeda. unchanged

b. halvedb. halved

c. doubledc. doubled

d. increase by 50percent d. increase by 50percent

6. The modulation index of an AM is 6. The modulation index of an AM is changed from 0 to 1. The changed from 0 to 1. The transmitted power istransmitted power is

a. unchangeda. unchanged

b. halvedb. halved

c. doubledc. doubled

d. increase by 50percentd. increase by 50percent

7. One of the advantages of base 7. One of the advantages of base modulation over collector modulation over collector modulation of a transistor class C modulation of a transistor class C amplifieramplifier

a. the lower the modulating power a. the lower the modulating power requiredrequired

b. high power output per transistorb. high power output per transistorc. better efficiencyc. better efficiencyd. better linearityd. better linearity

7. One of the advantages of base 7. One of the advantages of base modulation over collector modulation over collector modulation of a transistor class C modulation of a transistor class C amplifieramplifier

a. the lower the modulating power a. the lower the modulating power requiredrequired

b. high power output per transistorb. high power output per transistorc. better efficiencyc. better efficiencyd. better linearityd. better linearity

8. The carrier is simultaneously 8. The carrier is simultaneously modulated by two sine wave with the modulated by two sine wave with the modulation indices of 0.3 and 0.4; the modulation indices of 0.3 and 0.4; the total modulation indextotal modulation index

a. is 1a. is 1

b. cannot be calculated unless the phase b. cannot be calculated unless the phase relations are knownrelations are known

c. is 0.5c. is 0.5

d. is 0.7d. is 0.7

8. The carrier is simultaneously 8. The carrier is simultaneously modulated by two sine wave with the modulated by two sine wave with the modulation indices of 0.3 and 0.4; the modulation indices of 0.3 and 0.4; the total modulation indextotal modulation index

a. is 1a. is 1

b. cannot be calculated unless the phase b. cannot be calculated unless the phase relations are knownrelations are known

c. is 0.5c. is 0.5

d. is 0.7d. is 0.7

9. Amplitude modulation is used for 9. Amplitude modulation is used for broadcasting becausebroadcasting because

a. it is more noise immune than other a. it is more noise immune than other modulation systemmodulation system

b. compared with other system it b. compared with other system it requires less transmitting powerrequires less transmitting power

c. its use avoids receiver complexityc. its use avoids receiver complexityd. no other modulation system can d. no other modulation system can

provide the necessary bandwidth for provide the necessary bandwidth for high fidelityhigh fidelity

9. Amplitude modulation is used for 9. Amplitude modulation is used for broadcasting becausebroadcasting because

a. it is more noise immune than other a. it is more noise immune than other modulation systemmodulation system

b. compared with other system it b. compared with other system it requires less transmitting powerrequires less transmitting power

c. its use avoids receiver complexityc. its use avoids receiver complexityd. no other modulation system can d. no other modulation system can

provide the necessary bandwidth for provide the necessary bandwidth for high fidelityhigh fidelity

10. What is the ratio of the 10. What is the ratio of the modulating power to the total modulating power to the total power at 100 percent modulation?power at 100 percent modulation?

a. 1:3a. 1:3

b. 1:2b. 1:2

c. 2:3c. 2:3

d. None of the aboved. None of the above

10. What is the ratio of the 10. What is the ratio of the modulating power to the total modulating power to the total power at 100 percent modulation?power at 100 percent modulation?

a. 1:3a. 1:3

b. 1:2b. 1:2

c. 2:3c. 2:3

d. None of the aboved. None of the above

CHAPTER 4: SINGLE CHAPTER 4: SINGLE SIDE BAND SIDE BAND TECHNIQUESTECHNIQUES

1. Indicate the false statement 1. Indicate the false statement regarding the advantages of SSB regarding the advantages of SSB over double sideband, full carrier AM.over double sideband, full carrier AM.

a. More channel spaced availablea. More channel spaced availableb. Transmitter circuits must be more b. Transmitter circuits must be more

stable. Giving better reception.stable. Giving better reception.c. The signal is more noise-resistant.c. The signal is more noise-resistant.d. Much less power is required for the d. Much less power is required for the

same signal strengthsame signal strength

1. Indicate the false statement 1. Indicate the false statement regarding the advantages of SSB regarding the advantages of SSB over double sideband, full carrier AM.over double sideband, full carrier AM.

a. More channel spaced availablea. More channel spaced availableb. Transmitter circuits must be more b. Transmitter circuits must be more

stable. Giving better reception.stable. Giving better reception.c. The signal is more noise-resistant.c. The signal is more noise-resistant.d. Much less power is required for the d. Much less power is required for the

same signal strengthsame signal strength

2. When the modulation index of an AM 2. When the modulation index of an AM wave is doubled, the antenna current is wave is doubled, the antenna current is also doubled, the AM system being used also doubled, the AM system being used isis

a. Single sideband, full carrier (H3E)a. Single sideband, full carrier (H3E)

b. Vestigial sideband (C3F)b. Vestigial sideband (C3F)

c. Single-sideband, suppressed carrier c. Single-sideband, suppressed carrier (J3E)(J3E)

d. Double sideband, full carrier (A3E)d. Double sideband, full carrier (A3E)

2. When the modulation index of an AM 2. When the modulation index of an AM wave is doubled, the antenna current is wave is doubled, the antenna current is also doubled, the AM system being used also doubled, the AM system being used isis

a. Single sideband, full carrier (H3E)a. Single sideband, full carrier (H3E)

b. Vestigial sideband (C3F)b. Vestigial sideband (C3F)

c. Single-sideband, suppressed carrier c. Single-sideband, suppressed carrier (J3E)(J3E)

d. Double sideband, full carrier (A3E)d. Double sideband, full carrier (A3E)

3. Indicate which one of the following 3. Indicate which one of the following advantages of the phase cancellation method advantages of the phase cancellation method of obtaining SSB over the filter method is false:of obtaining SSB over the filter method is false:

a. Switching from one sideband to the other is a. Switching from one sideband to the other is simplersimpler

b. It is possible to generate SSB at any frequencyb. It is possible to generate SSB at any frequencyc. SSB with lower audio frequencies present can c. SSB with lower audio frequencies present can

be generatedbe generatedd. There are more balance modulator, therefore d. There are more balance modulator, therefore

the carrier is suppressed betterthe carrier is suppressed better

3. Indicate which one of the following 3. Indicate which one of the following advantages of the phase cancellation method advantages of the phase cancellation method of obtaining SSB over the filter method is false:of obtaining SSB over the filter method is false:

a. Switching from one sideband to the other is a. Switching from one sideband to the other is simplersimpler

b. It is possible to generate SSB at any frequencyb. It is possible to generate SSB at any frequencyc. SSB with lower audio frequencies present can c. SSB with lower audio frequencies present can

be generatedbe generatedd. There are more balance modulator, therefore d. There are more balance modulator, therefore

the carrier is suppressed betterthe carrier is suppressed better

4. The most common used filters in 4. The most common used filters in SSB generation areSSB generation are

a. mechanicala. mechanical

b. RCb. RC

c. LCc. LC

d. low-passd. low-pass

4. The most common used filters in 4. The most common used filters in SSB generation areSSB generation are

a. mechanicala. mechanical

b. RCb. RC

c. LCc. LC

d. low-passd. low-pass

5. In an SSB transmitter, one is 5. In an SSB transmitter, one is most likely to find amost likely to find a

a. class C audio amplifiera. class C audio amplifier

b. tuned modulatorb. tuned modulator

c. class B RF amplifierc. class B RF amplifier

d. class A RF output amplifierd. class A RF output amplifier

5. In an SSB transmitter, one is 5. In an SSB transmitter, one is most likely to find amost likely to find a

a. class C audio amplifiera. class C audio amplifier

b. tuned modulatorb. tuned modulator

c. class B RF amplifierc. class B RF amplifier

d. class A RF output amplifierd. class A RF output amplifier

6. Indicate in which of the following 6. Indicate in which of the following only one sideband is transmitted:only one sideband is transmitted:

a. H3Ea. H3E

b. A3Eb. A3E

c. B8Ec. B8E

d. C3Fd. C3F

6. Indicate in which of the following 6. Indicate in which of the following only one sideband is transmitted:only one sideband is transmitted:

a. H3Ea. H3E

b. A3Eb. A3E

c. B8Ec. B8E

d. C3Fd. C3F

7. One of the following cannot be 7. One of the following cannot be used to remove unwanted used to remove unwanted sideband in SSB. This is thesideband in SSB. This is the

a. Filter systema. Filter system

b. Phase shift methodb. Phase shift method

c. Third methodc. Third method

d. Balance modulatord. Balance modulator

7. One of the following cannot be 7. One of the following cannot be used to remove unwanted used to remove unwanted sideband in SSB. This is thesideband in SSB. This is the

a. Filter systema. Filter system

b. Phase shift methodb. Phase shift method

c. Third methodc. Third method

d. Balance modulatord. Balance modulator

8. R3E modulation is sometimes used to8. R3E modulation is sometimes used to

a. allow the receiver to have frequency a. allow the receiver to have frequency synthesizersynthesizer

b. simplify the frequency stability b. simplify the frequency stability problem receptionproblem reception

c. reduce the power that must be c. reduce the power that must be transmittedtransmitted

d. reduce the bandwidth required for d. reduce the bandwidth required for transmissiontransmission

8. R3E modulation is sometimes used to8. R3E modulation is sometimes used to

a. allow the receiver to have frequency a. allow the receiver to have frequency synthesizersynthesizer

b. simplify the frequency stability b. simplify the frequency stability problem receptionproblem reception

c. reduce the power that must be c. reduce the power that must be transmittedtransmitted

d. reduce the bandwidth required for d. reduce the bandwidth required for transmissiontransmission

9. To provide two or more voice 9. To provide two or more voice circuits with the same carrier, it is circuits with the same carrier, it is necessary to usenecessary to use

a. ISBa. ISB

b. Carrier reinsertionb. Carrier reinsertion

c. SSB with pilot carrierc. SSB with pilot carrier

d. Lincompexd. Lincompex

9. To provide two or more voice 9. To provide two or more voice circuits with the same carrier, it is circuits with the same carrier, it is necessary to usenecessary to use

a. ISBa. ISB

b. Carrier reinsertionb. Carrier reinsertion

c. SSB with pilot carrierc. SSB with pilot carrier

d. Lincompexd. Lincompex

10. Vestigial sideband modulation 10. Vestigial sideband modulation (C3F) is normally used for(C3F) is normally used for

a. HF point to point a. HF point to point communicationscommunications

b. Monoaural broadcastingb. Monoaural broadcasting

c. TV broadcastingc. TV broadcasting

d. Stereo broadcasting d. Stereo broadcasting

10. Vestigial sideband modulation 10. Vestigial sideband modulation (C3F) is normally used for(C3F) is normally used for

a. HF point to point a. HF point to point communicationscommunications

b. Monoaural broadcastingb. Monoaural broadcasting

c. TV broadcastingc. TV broadcasting

d. Stereo broadcasting d. Stereo broadcasting

CHAPTER 5: CHAPTER 5: FREQUENCY FREQUENCY MODULATIONMODULATION

1. In the stabilized reactance modulator 1. In the stabilized reactance modulator AFC system,AFC system,

a. the discriminator must have a fast a. the discriminator must have a fast time constant to prevent demodulationtime constant to prevent demodulation

b. the higher the discriminator frequency, b. the higher the discriminator frequency, the better the oscillator frequency the better the oscillator frequency stabilitystability

c. the discriminator frequency must not c. the discriminator frequency must not be too low, or the system will failbe too low, or the system will fail

d. phase modulation is converted into FM d. phase modulation is converted into FM by the equalizer circuitby the equalizer circuit

1. In the stabilized reactance modulator 1. In the stabilized reactance modulator AFC system,AFC system,

a. the discriminator must have a fast a. the discriminator must have a fast time constant to prevent demodulationtime constant to prevent demodulation

b. the higher the discriminator frequency, b. the higher the discriminator frequency, the better the oscillator frequency the better the oscillator frequency stabilitystability

c. the discriminator frequency must not c. the discriminator frequency must not be too low, or the system will failbe too low, or the system will fail

d. phase modulation is converted into FM d. phase modulation is converted into FM by the equalizer circuitby the equalizer circuit

2. In the spectrum of a frequency 2. In the spectrum of a frequency modulated wavemodulated wave

a. the carrier frequency disappears when a. the carrier frequency disappears when the modulation index is largethe modulation index is large

b. the amplitude of any sideband b. the amplitude of any sideband depends on the modulation indexdepends on the modulation index

c. the total number of sidebands depend c. the total number of sidebands depend on the modulation indexon the modulation index

d. the carrier frequency cannot disappeard. the carrier frequency cannot disappear

2. In the spectrum of a frequency 2. In the spectrum of a frequency modulated wavemodulated wave

a. the carrier frequency disappears when a. the carrier frequency disappears when the modulation index is largethe modulation index is large

b. the amplitude of any sideband b. the amplitude of any sideband depends on the modulation indexdepends on the modulation index

c. the total number of sidebands depend c. the total number of sidebands depend on the modulation indexon the modulation index

d. the carrier frequency cannot disappeard. the carrier frequency cannot disappear

3. The difference between the phase 3. The difference between the phase and frequency modulationand frequency modulation

a. is purely theoretical because they a. is purely theoretical because they are the same in practiceare the same in practice

b. is too great to make the two b. is too great to make the two system compatiblesystem compatible

c. lies in the poorer audio response c. lies in the poorer audio response of the phase modulationof the phase modulation

d. lies in the different definitions of d. lies in the different definitions of the modulation indexthe modulation index

3. The difference between the phase 3. The difference between the phase and frequency modulationand frequency modulation

a. is purely theoretical because they a. is purely theoretical because they are the same in practiceare the same in practice

b. is too great to make the two b. is too great to make the two system compatiblesystem compatible

c. lies in the poorer audio response c. lies in the poorer audio response of the phase modulationof the phase modulation

d. lies in the different definitions of d. lies in the different definitions of the modulation indexthe modulation index

4. Indicate the false statement regarding 4. Indicate the false statement regarding the Armstrong modulation system,the Armstrong modulation system,

a. the system is basically phase and not a. the system is basically phase and not frequency modulation.frequency modulation.

b. AFC is not needed, as the crystal b. AFC is not needed, as the crystal oscillator is used.oscillator is used.

c. Frequency multiplications must be c. Frequency multiplications must be usedused

d. Equalization is unnecessary.d. Equalization is unnecessary.

4. Indicate the false statement regarding 4. Indicate the false statement regarding the Armstrong modulation system,the Armstrong modulation system,

a. the system is basically phase and not a. the system is basically phase and not frequency modulation.frequency modulation.

b. AFC is not needed, as the crystal b. AFC is not needed, as the crystal oscillator is used.oscillator is used.

c. Frequency multiplications must be c. Frequency multiplications must be usedused

d. Equalization is unnecessary.d. Equalization is unnecessary.

5. An FM signal with a modulation index 5. An FM signal with a modulation index mf is passed through the frequency mf is passed through the frequency tripler. The wave in the output of the tripler. The wave in the output of the Tripler will have a modulation index ofTripler will have a modulation index of

a. mf/3a. mf/3

b. mfb. mf

c. 3mfc. 3mf

d. 9mfd. 9mf

5. An FM signal with a modulation index 5. An FM signal with a modulation index mf is passed through the frequency mf is passed through the frequency tripler. The wave in the output of the tripler. The wave in the output of the Tripler will have a modulation index ofTripler will have a modulation index of

a. mf/3a. mf/3

b. mfb. mf

c. 3mfc. 3mf

d. 9mfd. 9mf

6. An FM signal with a deviation (δ) is 6. An FM signal with a deviation (δ) is passed through a mixer, and has passed through a mixer, and has its frequency reduced fivefold. The its frequency reduced fivefold. The deviation in the output of the mixer deviation in the output of the mixer isis

a. 5 δa. 5 δb. Indeterminateb. Indeterminatec. δ / 5c. δ / 5d. δd. δ

6. An FM signal with a deviation (δ) is 6. An FM signal with a deviation (δ) is passed through a mixer, and has passed through a mixer, and has its frequency reduced fivefold. The its frequency reduced fivefold. The deviation in the output of the mixer deviation in the output of the mixer isis

a. 5 δa. 5 δb. Indeterminateb. Indeterminatec. δ / 5c. δ / 5d. δd. δ

7. A pre-emphasis circuit provides 7. A pre-emphasis circuit provides extra noise immunity byextra noise immunity by

a. boosting the bass frequencya. boosting the bass frequency

b. amplifying the high audio b. amplifying the high audio frequenciesfrequencies

c. preamplifying the whole audio bandc. preamplifying the whole audio band

d. converting the phase modulation to d. converting the phase modulation to FMFM

7. A pre-emphasis circuit provides 7. A pre-emphasis circuit provides extra noise immunity byextra noise immunity by

a. boosting the bass frequencya. boosting the bass frequency

b. amplifying the high audio b. amplifying the high audio frequenciesfrequencies

c. preamplifying the whole audio bandc. preamplifying the whole audio band

d. converting the phase modulation to d. converting the phase modulation to FMFM

8. Since noise phase modulates the 8. Since noise phase modulates the FM wave, as the noise sideband FM wave, as the noise sideband frequency approaches the carrier frequency approaches the carrier frequency, the noise amplitudefrequency, the noise amplitude

a. remains constanta. remains constantb. is decreasedb. is decreasedc. is increasedc. is increasedd. is equalizedd. is equalized

8. Since noise phase modulates the 8. Since noise phase modulates the FM wave, as the noise sideband FM wave, as the noise sideband frequency approaches the carrier frequency approaches the carrier frequency, the noise amplitudefrequency, the noise amplitude

a. remains constanta. remains constantb. is decreasedb. is decreasedc. is increasedc. is increasedd. is equalizedd. is equalized

9. When the modulating frequency 9. When the modulating frequency is doubled, the modulation index is doubled, the modulation index is halved, and the modulating is halved, and the modulating voltage remains constant. The voltage remains constant. The modulation system ismodulation system is

a. amplitude modulationa. amplitude modulationb. phase modulationb. phase modulationc. frequency modulationc. frequency modulationd. any one of the threed. any one of the three

9. When the modulating frequency 9. When the modulating frequency is doubled, the modulation index is doubled, the modulation index is halved, and the modulating is halved, and the modulating voltage remains constant. The voltage remains constant. The modulation system ismodulation system is

a. amplitude modulationa. amplitude modulationb. phase modulationb. phase modulationc. frequency modulationc. frequency modulationd. any one of the threed. any one of the three

10. Indicate which one of the following is 10. Indicate which one of the following is not an advantage of FM over AM:not an advantage of FM over AM:

a. Better noise immunity is provideda. Better noise immunity is provided

b. Lower bandwidth is requiredb. Lower bandwidth is required

c. The transmitted power is more usefulc. The transmitted power is more useful

d. Less modulating power is required d. Less modulating power is required

10. Indicate which one of the following is 10. Indicate which one of the following is not an advantage of FM over AM:not an advantage of FM over AM:

a. Better noise immunity is provideda. Better noise immunity is provided

b. Lower bandwidth is requiredb. Lower bandwidth is required

c. The transmitted power is more usefulc. The transmitted power is more useful

d. Less modulating power is required d. Less modulating power is required

11. One of the following is an in 11. One of the following is an in direct way of generating FM. This is direct way of generating FM. This is thethe

a. Reactance FET modulatora. Reactance FET modulator

b. Varactor diodeb. Varactor diode

c. Armstrong modulatorc. Armstrong modulator

d. Reactance bipolar transistor d. Reactance bipolar transistor modulatormodulator

11. One of the following is an in 11. One of the following is an in direct way of generating FM. This is direct way of generating FM. This is thethe

a. Reactance FET modulatora. Reactance FET modulator

b. Varactor diodeb. Varactor diode

c. Armstrong modulatorc. Armstrong modulator

d. Reactance bipolar transistor d. Reactance bipolar transistor modulatormodulator

12. In an FM stereo multiplex 12. In an FM stereo multiplex transmission, thetransmission, the

a. sum signal modulates the 19KHz sub a. sum signal modulates the 19KHz sub carriercarrier

b. difference signal modulates the 19KHz b. difference signal modulates the 19KHz sub carriersub carrier

c. difference signal modulates the 38KHz c. difference signal modulates the 38KHz sub carriersub carrier

d. difference signal modulates the 67KHz d. difference signal modulates the 67KHz sub carriersub carrier

12. In an FM stereo multiplex 12. In an FM stereo multiplex transmission, thetransmission, the

a. sum signal modulates the 19KHz sub a. sum signal modulates the 19KHz sub carriercarrier

b. difference signal modulates the 19KHz b. difference signal modulates the 19KHz sub carriersub carrier

c. difference signal modulates the 38KHz c. difference signal modulates the 38KHz sub carriersub carrier

d. difference signal modulates the 67KHz d. difference signal modulates the 67KHz sub carriersub carrier

CHAPTER 6: RADIO CHAPTER 6: RADIO RECEIVERS RECEIVERS

1. Indicate which of the following 1. Indicate which of the following statement about the advantages statement about the advantages of the phase discriminator over of the phase discriminator over the slope detector is false:the slope detector is false:

a. much easier alignmenta. much easier alignmentb. better linearityb. better linearityc. great limitingc. great limitingd. fewer tuned circuits d. fewer tuned circuits

1. Indicate which of the following 1. Indicate which of the following statement about the advantages statement about the advantages of the phase discriminator over of the phase discriminator over the slope detector is false:the slope detector is false:

a. much easier alignmenta. much easier alignmentb. better linearityb. better linearityc. great limitingc. great limitingd. fewer tuned circuits d. fewer tuned circuits

2. Show which of the following 2. Show which of the following statement about the amplitude limiter statement about the amplitude limiter is untrue:is untrue:

a. the circuit is always biased in class C, a. the circuit is always biased in class C, by the virtue of the leak type biasby the virtue of the leak type bias

b. when the input increases past the b. when the input increases past the threshold of limiting, the gain threshold of limiting, the gain decreases to keep the output constantdecreases to keep the output constant

c. the output must be tunedc. the output must be tunedd. leak type biased must be usedd. leak type biased must be used

2. Show which of the following 2. Show which of the following statement about the amplitude limiter statement about the amplitude limiter is untrue:is untrue:

a. the circuit is always biased in class C, a. the circuit is always biased in class C, by the virtue of the leak type biasby the virtue of the leak type bias

b. when the input increases past the b. when the input increases past the threshold of limiting, the gain threshold of limiting, the gain decreases to keep the output constantdecreases to keep the output constant

c. the output must be tunedc. the output must be tunedd. leak type biased must be usedd. leak type biased must be used

3. In a radio receiver with simple 3. In a radio receiver with simple AGCAGC

a. an increase in signal strength a. an increase in signal strength produces more AGCproduces more AGC

b. the audio stage gain is normally b. the audio stage gain is normally controlled by the AGCcontrolled by the AGC

c. the faster the AGC time constant, c. the faster the AGC time constant, the more accurate the outputthe more accurate the output

d. the highest AGC voltage is d. the highest AGC voltage is produced between stationsproduced between stations

3. In a radio receiver with simple 3. In a radio receiver with simple AGCAGC

a. an increase in signal strength a. an increase in signal strength produces more AGCproduces more AGC

b. the audio stage gain is normally b. the audio stage gain is normally controlled by the AGCcontrolled by the AGC

c. the faster the AGC time constant, c. the faster the AGC time constant, the more accurate the outputthe more accurate the output

d. the highest AGC voltage is d. the highest AGC voltage is produced between stationsproduced between stations

4. In broadcast super heterodyne 4. In broadcast super heterodyne receiver, thereceiver, the

a. local oscillator operates below the a. local oscillator operates below the signal frequencysignal frequency

b. mixer input must be tuned to the b. mixer input must be tuned to the signal frequencysignal frequency

c. local oscillator frequency is normally c. local oscillator frequency is normally double the IFdouble the IF

d. RF amplifier normally works at 455KHz d. RF amplifier normally works at 455KHz above the carrier frequencyabove the carrier frequency

4. In broadcast super heterodyne 4. In broadcast super heterodyne receiver, thereceiver, the

a. local oscillator operates below the a. local oscillator operates below the signal frequencysignal frequency

b. mixer input must be tuned to the b. mixer input must be tuned to the signal frequencysignal frequency

c. local oscillator frequency is normally c. local oscillator frequency is normally double the IFdouble the IF

d. RF amplifier normally works at 455KHz d. RF amplifier normally works at 455KHz above the carrier frequencyabove the carrier frequency

5. To prevent overloading of the 5. To prevent overloading of the last IF amplifier in the receiver, last IF amplifier in the receiver, one should useone should use

a. squelcha. squelch

b. variable sensitivityb. variable sensitivity

c. variable selectivityc. variable selectivity

d. double conversiond. double conversion

5. To prevent overloading of the 5. To prevent overloading of the last IF amplifier in the receiver, last IF amplifier in the receiver, one should useone should use

a. squelcha. squelch

b. variable sensitivityb. variable sensitivity

c. variable selectivityc. variable selectivity

d. double conversiond. double conversion

6. A super heterodyne receiver with 6. A super heterodyne receiver with an IF of 450KHz is tuned to a signal an IF of 450KHz is tuned to a signal at 1200KHz. The image frequency at 1200KHz. The image frequency isis

a. 750KHza. 750KHz

b. 900KHzb. 900KHz

c. 1650KHzc. 1650KHz

d. 2100KHz d. 2100KHz

6. A super heterodyne receiver with 6. A super heterodyne receiver with an IF of 450KHz is tuned to a signal an IF of 450KHz is tuned to a signal at 1200KHz. The image frequency at 1200KHz. The image frequency isis

a. 750KHza. 750KHz

b. 900KHzb. 900KHz

c. 1650KHzc. 1650KHz

d. 2100KHzd. 2100KHz

7. In a radio detector7. In a radio detectora. the linearity is worse than in phase a. the linearity is worse than in phase

discriminatordiscriminatorb. stabilization against signal strength b. stabilization against signal strength

variations is providedvariations is providedc. the output is twice that obtainable c. the output is twice that obtainable

from a similar phase discriminatorfrom a similar phase discriminatord. the circuit is the same as in a d. the circuit is the same as in a

discriminator, except that the diodes discriminator, except that the diodes are reversedare reversed

7. In a radio detector7. In a radio detectora. the linearity is worse than in phase a. the linearity is worse than in phase

discriminatordiscriminatorb. stabilization against signal strength b. stabilization against signal strength

variations is providedvariations is providedc. the output is twice that obtainable c. the output is twice that obtainable

from a similar phase discriminatorfrom a similar phase discriminatord. the circuit is the same as in a d. the circuit is the same as in a

discriminator, except that the diodes discriminator, except that the diodes are reversedare reversed

8. The typical squelch circuit cuts off8. The typical squelch circuit cuts offa. an audio amplifier when the carrier a. an audio amplifier when the carrier

is absentis absentb. RF interference when the signal is b. RF interference when the signal is

weakweakc. an IF amplifier when the AGC is c. an IF amplifier when the AGC is

maximummaximumd. an IF amplifier when the AGC is d. an IF amplifier when the AGC is

minimumminimum

8. The typical squelch circuit cuts off8. The typical squelch circuit cuts offa. an audio amplifier when the carrier a. an audio amplifier when the carrier

is absentis absentb. RF interference when the signal is b. RF interference when the signal is

weakweakc. an IF amplifier when the AGC is c. an IF amplifier when the AGC is

maximummaximumd. an IF amplifier when the AGC is d. an IF amplifier when the AGC is

minimumminimum

9. Indicate the false statement in 9. Indicate the false statement in connection with the communications connection with the communications receivers.receivers.

a. The noise limiter cuts off the receiver’s a. The noise limiter cuts off the receiver’s output during a noise pulse.output during a noise pulse.

b. A product demodulator could be used b. A product demodulator could be used for the reception of morse codefor the reception of morse code

c. Double conversion is used to improve c. Double conversion is used to improve image rejectionimage rejection

d. Variable sensitivity is used to eliminate d. Variable sensitivity is used to eliminate selective fadingselective fading

9. Indicate the false statement in 9. Indicate the false statement in connection with the communications connection with the communications receivers.receivers.

a. The noise limiter cuts off the receiver’s a. The noise limiter cuts off the receiver’s output during a noise pulse.output during a noise pulse.

b. A product demodulator could be used b. A product demodulator could be used for the reception of morse codefor the reception of morse code

c. Double conversion is used to improve c. Double conversion is used to improve image rejectionimage rejection

d. Variable sensitivity is used to eliminate d. Variable sensitivity is used to eliminate selective fadingselective fading

10. The controlled oscillator 10. The controlled oscillator synthesizer is sometimes preferred synthesizer is sometimes preferred to the direct one becauseto the direct one because

a. it is simpler piece of equipmenta. it is simpler piece of equipmentb. its frequency stability is betterb. its frequency stability is betterc. it does not require crystal c. it does not require crystal

oscillatorsoscillatorsd. it is relatively free of spurious d. it is relatively free of spurious

frequencies frequencies

10. The controlled oscillator 10. The controlled oscillator synthesizer is sometimes preferred synthesizer is sometimes preferred to the direct one becauseto the direct one because

a. it is simpler piece of equipmenta. it is simpler piece of equipmentb. its frequency stability is betterb. its frequency stability is betterc. it does not require crystal c. it does not require crystal

oscillatorsoscillatorsd. it is relatively free of spurious d. it is relatively free of spurious

frequencies frequencies

10. The controlled oscillator 10. The controlled oscillator synthesizer is sometimes preferred synthesizer is sometimes preferred to the direct one becauseto the direct one because

a. it is simpler piece of equipmenta. it is simpler piece of equipmentb. its frequency stability is betterb. its frequency stability is betterc. it does not require crystal c. it does not require crystal

oscillatorsoscillatorsd. it is relatively free of spurious d. it is relatively free of spurious

frequenciesfrequencies

11. The frequency generated by each 11. The frequency generated by each decade in a direct frequency synthesizer decade in a direct frequency synthesizer is much higher than the frequency is much higher than the frequency shown; this is done toshown; this is done to

a. reduce the spurious frequency problema. reduce the spurious frequency problem

b. increase the frequency stability of the b. increase the frequency stability of the synthesizersynthesizer

c. reduce the number of decadesc. reduce the number of decades

d. reduce the number of crystal requiredd. reduce the number of crystal required

11. The frequency generated by each 11. The frequency generated by each decade in a direct frequency synthesizer decade in a direct frequency synthesizer is much higher than the frequency is much higher than the frequency shown; this is done toshown; this is done to

a. reduce the spurious frequency problema. reduce the spurious frequency problem

b. increase the frequency stability of the b. increase the frequency stability of the synthesizersynthesizer

c. reduce the number of decadesc. reduce the number of decades

d. reduce the number of crystal requiredd. reduce the number of crystal required

12. Indicated which of the following 12. Indicated which of the following circuits could not demodulate circuits could not demodulate SSB.SSB.

a. Balance modulatora. Balance modulator

b. Product detectorb. Product detector

c. BFOc. BFO

d. Phase discriminator d. Phase discriminator

12. Indicated which of the following 12. Indicated which of the following circuits could not demodulate circuits could not demodulate SSB.SSB.

a. Balance modulatora. Balance modulator

b. Product detectorb. Product detector

c. BFOc. BFO

d. Phase discriminatord. Phase discriminator

13. If an FET is used as the first AF 13. If an FET is used as the first AF amplifier in a transistor receiver, this amplifier in a transistor receiver, this will have the effect ofwill have the effect of

a. improving the effectiveness of the AGCa. improving the effectiveness of the AGCb. reducing the effect of negative peak b. reducing the effect of negative peak

clippingclippingc. reducing the effect of noise at low c. reducing the effect of noise at low

modulation depthsmodulation depthsd. improving the selectivity of the d. improving the selectivity of the

receiverreceiver

13. If an FET is used as the first AF 13. If an FET is used as the first AF amplifier in a transistor receiver, this amplifier in a transistor receiver, this will have the effect ofwill have the effect of

a. improving the effectiveness of the AGCa. improving the effectiveness of the AGCb. reducing the effect of negative peak b. reducing the effect of negative peak

clippingclippingc. reducing the effect of noise at low c. reducing the effect of noise at low

modulation depthsmodulation depthsd. improving the selectivity of the d. improving the selectivity of the

receiverreceiver

14. Indicate the false statement. The super 14. Indicate the false statement. The super heterodyne receiver replaced the TRF heterodyne receiver replaced the TRF receiver because the latter suffered fromreceiver because the latter suffered from

a. gain variation over the frequency a. gain variation over the frequency coverage rangecoverage range

b. insufficient gain and sensitivityb. insufficient gain and sensitivity

c. inadequate selectivity at high c. inadequate selectivity at high frequenciesfrequencies

d. instabilityd. instability

14. Indicate the false statement. The super 14. Indicate the false statement. The super heterodyne receiver replaced the TRF heterodyne receiver replaced the TRF receiver because the latter suffered fromreceiver because the latter suffered from

a. gain variation over the frequency a. gain variation over the frequency coverage rangecoverage range

b. insufficient gain and sensitivityb. insufficient gain and sensitivity

c. inadequate selectivity at high c. inadequate selectivity at high frequenciesfrequencies

d. instabilityd. instability

15. The image frequency of a super 15. The image frequency of a super heterodyne receiverheterodyne receiver

a. is created within the receiver itselfa. is created within the receiver itselfb. is due to insufficient adjacent b. is due to insufficient adjacent

channel rejectionchannel rejectionc. is not rejected by the IF tuned c. is not rejected by the IF tuned

circuitscircuitsd. is independent of the frequency to d. is independent of the frequency to

which the receiver is tunedwhich the receiver is tuned

15. The image frequency of a super 15. The image frequency of a super heterodyne receiverheterodyne receiver

a. is created within the receiver itselfa. is created within the receiver itselfb. is due to insufficient adjacent b. is due to insufficient adjacent

channel rejectionchannel rejectionc. is not rejected by the IF tuned c. is not rejected by the IF tuned

circuitscircuitsd. is independent of the frequency to d. is independent of the frequency to

which the receiver is tunedwhich the receiver is tuned

16. One of the main functions of the RF 16. One of the main functions of the RF amplifier in a super heterodyne receiver is amplifier in a super heterodyne receiver is toto

a. provide improved trackinga. provide improved tracking

b. permit better adjacent-channel rejectionb. permit better adjacent-channel rejection

c. increase the tuning range of the receiverc. increase the tuning range of the receiver

d. improve the rejection of the image d. improve the rejection of the image frequencyfrequency

16. One of the main functions of the RF 16. One of the main functions of the RF amplifier in a super heterodyne receiver is amplifier in a super heterodyne receiver is toto

a. provide improved trackinga. provide improved tracking

b. permit better adjacent-channel rejectionb. permit better adjacent-channel rejection

c. increase the tuning range of the receiverc. increase the tuning range of the receiver

d. improve the rejection of the image d. improve the rejection of the image frequencyfrequency

17. A receiver has poor IF 17. A receiver has poor IF selectivity. It will therefore also selectivity. It will therefore also have poorhave poor

a. blockinga. blocking

b. double spottingb. double spotting

c. diversity receptionc. diversity reception

d. sensitivityd. sensitivity

17. A receiver has poor IF 17. A receiver has poor IF selectivity. It will therefore also selectivity. It will therefore also have poorhave poor

a. blockinga. blocking

b. double spottingb. double spotting

c. diversity receptionc. diversity reception

d. sensitivityd. sensitivity

18. Three point tracking is achieved 18. Three point tracking is achieved withwith

a. variable selectivitya. variable selectivity

b. the padder capacitorb. the padder capacitor

c. double spottingc. double spotting

d. double conversion d. double conversion

18. Three point tracking is achieved 18. Three point tracking is achieved withwith

a. variable selectivitya. variable selectivity

b. the padder capacitorb. the padder capacitor

c. double spottingc. double spotting

d. double conversion d. double conversion

19. The local oscillator of a broadcast 19. The local oscillator of a broadcast receiver is tuned to a frequency receiver is tuned to a frequency higher that the incoming frequencyhigher that the incoming frequency

a. to help the image frequency rejectiona. to help the image frequency rejectionb. to permit easier trackingb. to permit easier trackingc. because otherwise an intermediate c. because otherwise an intermediate

frequency could not be producedfrequency could not be producedd. to allow adequate frequency d. to allow adequate frequency

coverage without switchingcoverage without switching

19. The local oscillator of a broadcast 19. The local oscillator of a broadcast receiver is tuned to a frequency receiver is tuned to a frequency higher that the incoming frequencyhigher that the incoming frequency

a. to help the image frequency rejectiona. to help the image frequency rejectionb. to permit easier trackingb. to permit easier trackingc. because otherwise an intermediate c. because otherwise an intermediate

frequency could not be producedfrequency could not be producedd. to allow adequate frequency d. to allow adequate frequency

coverage without switchingcoverage without switching

20. If the intermediate frequency is 20. If the intermediate frequency is very high (indicate the false very high (indicate the false statement)statement)

a. image frequency rejection is very a. image frequency rejection is very goodgood

b. the local oscillator need to be b. the local oscillator need to be extremely stableextremely stable

c. the selectivity will be poorc. the selectivity will be poord. tracking will be improvedd. tracking will be improved

20. If the intermediate frequency is 20. If the intermediate frequency is very high (indicate the false very high (indicate the false statement)statement)

a. image frequency rejection is very a. image frequency rejection is very goodgood

b. the local oscillator need to be b. the local oscillator need to be extremely stableextremely stable

c. the selectivity will be poorc. the selectivity will be poord. tracking will be improvedd. tracking will be improved

21. A low ratio of the AC to the DC 21. A low ratio of the AC to the DC load impedance of a diode load impedance of a diode detector results indetector results in

a. diagonal clippinga. diagonal clipping

b. poor AGC operationb. poor AGC operation

c. negative-peak clippingc. negative-peak clipping

d. poor AF responsed. poor AF response

21. A low ratio of the AC to the DC 21. A low ratio of the AC to the DC load impedance of a diode load impedance of a diode detector results indetector results in

a. diagonal clippinga. diagonal clipping

b. poor AGC operationb. poor AGC operation

c. negative-peak clippingc. negative-peak clipping

d. poor AF responsed. poor AF response

22. On of the following cannot be 22. On of the following cannot be used to demodulate SSB.used to demodulate SSB.

a. product detectora. product detector

b. diode balance modulatorb. diode balance modulator

c. bipolar transistor balance c. bipolar transistor balance modulatormodulator

d. complete phase-shift generatord. complete phase-shift generator

22. On of the following cannot be 22. On of the following cannot be used to demodulate SSB.used to demodulate SSB.

a. product detectora. product detector

b. diode balance modulatorb. diode balance modulator

c. bipolar transistor balance c. bipolar transistor balance modulatormodulator

d. complete phase-shift generatord. complete phase-shift generator

23. Indicate the false statement. Nothing 23. Indicate the false statement. Nothing that no carrier is transmitted with J3E, we that no carrier is transmitted with J3E, we see thatsee that

a. the receiver cannot use a phase a. the receiver cannot use a phase comparator for AFCcomparator for AFC

b. adjacent-channel rejection is more difficultb. adjacent-channel rejection is more difficultc. production of AGC is rather complicated c. production of AGC is rather complicated

processprocessd. the transmission is not compatible with d. the transmission is not compatible with

A3EA3E

23. Indicate the false statement. Nothing 23. Indicate the false statement. Nothing that no carrier is transmitted with J3E, we that no carrier is transmitted with J3E, we see thatsee that

a. the receiver cannot use a phase a. the receiver cannot use a phase comparator for AFCcomparator for AFC

b. adjacent-channel rejection is more difficultb. adjacent-channel rejection is more difficultc. production of AGC is rather complicated c. production of AGC is rather complicated

processprocessd. the transmission is not compatible with d. the transmission is not compatible with

A3EA3E

24. When the receiver has good 24. When the receiver has good blocking performance, this means blocking performance, this means thatthat

a. it does not suffer from double a. it does not suffer from double spottingspotting

b. its image frequency rejection is poorb. its image frequency rejection is poorc. it is unaffected by AGC derived from c. it is unaffected by AGC derived from

nearby transmissionnearby transmissiond. its detector suffers from burnoutd. its detector suffers from burnout

24. When the receiver has good 24. When the receiver has good blocking performance, this means blocking performance, this means thatthat

a. it does not suffer from double a. it does not suffer from double spottingspotting

b. its image frequency rejection is poorb. its image frequency rejection is poorc. it is unaffected by AGC derived from c. it is unaffected by AGC derived from

nearby transmissionnearby transmissiond. its detector suffers from burnoutd. its detector suffers from burnout

25. An AM receiver uses a diode 25. An AM receiver uses a diode detector to demodulation. This detector to demodulation. This enables it satisfactorily to receiveenables it satisfactorily to receive

a. single sideband, suppressed a. single sideband, suppressed carriercarrier

b. single sideband, reduced carrierb. single sideband, reduced carrier

c. ISBc. ISB

d. Single sideband, full carrierd. Single sideband, full carrier

25. An AM receiver uses a diode 25. An AM receiver uses a diode detector to demodulation. This detector to demodulation. This enables it satisfactorily to receiveenables it satisfactorily to receive

a. single sideband, suppressed a. single sideband, suppressed carriercarrier

b. single sideband, reduced carrierb. single sideband, reduced carrier

c. ISBc. ISB

d. Single sideband, full carrierd. Single sideband, full carrier

CHAPTER 7: CHAPTER 7: TRANSMISSION LINESTRANSMISSION LINES

1. Indicate the false statement. The 1. Indicate the false statement. The SWR on a transmission line SWR on a transmission line infinity; the line is terminated ininfinity; the line is terminated in

a. a short circuita. a short circuit

b. a complex impedanceb. a complex impedance

c. an open circuitc. an open circuit

d. a pure resistanced. a pure resistance

1. Indicate the false statement. The 1. Indicate the false statement. The SWR on a transmission line SWR on a transmission line infinity; the line is terminated ininfinity; the line is terminated in

a. a short circuita. a short circuit

b. a complex impedanceb. a complex impedance

c. an open circuitc. an open circuit

d. a pure resistanced. a pure resistance

2. A (75 - j50) load is connected to a 2. A (75 - j50) load is connected to a coaxial transmission line of Zo = 75, coaxial transmission line of Zo = 75, at 10GHz. The best method of at 10GHz. The best method of matching consists in connectingmatching consists in connecting

a. a short circuited stub at the loada. a short circuited stub at the loadb. an inductance at the loadb. an inductance at the loadc. a capacitance at some specific c. a capacitance at some specific

distance from the loaddistance from the loadd. a short circuited stub at some d. a short circuited stub at some

specific distance from the loadspecific distance from the load

2. A (75 - j50) load is connected to a 2. A (75 - j50) load is connected to a coaxial transmission line of Zo = 75, coaxial transmission line of Zo = 75, at 10GHz. The best method of at 10GHz. The best method of matching consists in connectingmatching consists in connecting

a. a short circuited stub at the loada. a short circuited stub at the loadb. an inductance at the loadb. an inductance at the loadc. a capacitance at some specific c. a capacitance at some specific

distance from the loaddistance from the loadd. a short circuited stub at some d. a short circuited stub at some

specific distance from the loadspecific distance from the load

3. The velocity factor of a transmission 3. The velocity factor of a transmission lineline

a. depends on the dielectric constant of a. depends on the dielectric constant of the material usedthe material used

b. increase the velocity along the b. increase the velocity along the transmission linetransmission line

c. is governed by the skin effectc. is governed by the skin effect

d. is higher for a solid dielectric than for d. is higher for a solid dielectric than for airair

3. The velocity factor of a transmission 3. The velocity factor of a transmission lineline

a. depends on the dielectric constant of a. depends on the dielectric constant of the material usedthe material used

b. increase the velocity along the b. increase the velocity along the transmission linetransmission line

c. is governed by the skin effectc. is governed by the skin effect

d. is higher for a solid dielectric than for d. is higher for a solid dielectric than for airair

4. Impedance inversion may be 4. Impedance inversion may be obtained withobtained with

a. a short circuited stuba. a short circuited stub

b. an open circuited stubb. an open circuited stub

c. a quarter wave linec. a quarter wave line

d. a half wave lined. a half wave line

4. Impedance inversion may be 4. Impedance inversion may be obtained withobtained with

a. a short circuited stuba. a short circuited stub

b. an open circuited stubb. an open circuited stub

c. a quarter wave linec. a quarter wave line

d. a half wave lined. a half wave line

5. Short-circuited stubs are preferred to 5. Short-circuited stubs are preferred to open circuited stub because the latter open circuited stub because the latter areare

a. more difficult to make and connecta. more difficult to make and connect

b. made of transmission line with a b. made of transmission line with a different characteristic impedancedifferent characteristic impedance

c. liable to radiatec. liable to radiate

d. incapable of giving a full range of d. incapable of giving a full range of reactancereactance

5. Short-circuited stubs are preferred to 5. Short-circuited stubs are preferred to open circuited stub because the latter open circuited stub because the latter areare

a. more difficult to make and connecta. more difficult to make and connect

b. made of transmission line with a b. made of transmission line with a different characteristic impedancedifferent characteristic impedance

c. liable to radiatec. liable to radiate

d. incapable of giving a full range of d. incapable of giving a full range of reactancereactance

6. For a transmission line load 6. For a transmission line load matching over a range of matching over a range of frequencies, it is best to use afrequencies, it is best to use a

a. baluna. balun

b. broadband directional couplerb. broadband directional coupler

c. double stubc. double stub

d. single stud of adjustable positiond. single stud of adjustable position

6. For a transmission line load 6. For a transmission line load matching over a range of matching over a range of frequencies, it is best to use afrequencies, it is best to use a

a. baluna. balun

b. broadband directional couplerb. broadband directional coupler

c. double stubc. double stub

d. single stud of adjustable positiond. single stud of adjustable position

7. The main disadvantage of the 7. The main disadvantage of the two hole directional couple istwo hole directional couple is

a. low directional couplinga. low directional coupling

b. poor directivityb. poor directivity

c. high SWRc. high SWR

d. narrow bandwidthd. narrow bandwidth

7. The main disadvantage of the 7. The main disadvantage of the two hole directional couple istwo hole directional couple is

a. low directional couplinga. low directional coupling

b. poor directivityb. poor directivity

c. high SWRc. high SWR

d. narrow bandwidthd. narrow bandwidth

8. To couple a coaxial line to a 8. To couple a coaxial line to a parallel wire, it is best to use aparallel wire, it is best to use a

a. slotted linea. slotted line

b. balunb. balun

c. directional couplerc. directional coupler

d. quarter wave transformerd. quarter wave transformer

8. To couple a coaxial line to a 8. To couple a coaxial line to a parallel wire, it is best to use aparallel wire, it is best to use a

a. slotted linea. slotted line

b. balunb. balun

c. directional couplerc. directional coupler

d. quarter wave transformerd. quarter wave transformer

9. Indicate the three types of 9. Indicate the three types of transmission line energy lossestransmission line energy losses

a. (I^2)R, RL, and temperaturea. (I^2)R, RL, and temperature

b. Radiation, (I^2)R, and dielectric b. Radiation, (I^2)R, and dielectric heatingheating

c. Dielectric separation, insulation c. Dielectric separation, insulation breakdown, and radiationbreakdown, and radiation

d. Conductor heating, dielectric heating, d. Conductor heating, dielectric heating, and radiation resistanceand radiation resistance

9. Indicate the three types of 9. Indicate the three types of transmission line energy lossestransmission line energy losses

a. (I^2)R, RL, and temperaturea. (I^2)R, RL, and temperature

b. Radiation, (I^2)R, and dielectric b. Radiation, (I^2)R, and dielectric heatingheating

c. Dielectric separation, insulation c. Dielectric separation, insulation breakdown, and radiationbreakdown, and radiation

d. Conductor heating, dielectric heating, d. Conductor heating, dielectric heating, and radiation resistanceand radiation resistance

10. Indicate the true statement below. 10. Indicate the true statement below. The directional coupler isThe directional coupler is

a. A device used to connect a a. A device used to connect a transmitter to a directional antennatransmitter to a directional antenna

b. A coupling device for matching b. A coupling device for matching impedanceimpedance

c. A device used to measure c. A device used to measure transmission line powertransmission line power

d. An SWR measuring instrumentd. An SWR measuring instrument

10. Indicate the true statement below. 10. Indicate the true statement below. The directional coupler isThe directional coupler is

a. A device used to connect a a. A device used to connect a transmitter to a directional antennatransmitter to a directional antenna

b. A coupling device for matching b. A coupling device for matching impedanceimpedance

c. A device used to measure c. A device used to measure transmission line powertransmission line power

d. An SWR measuring instrumentd. An SWR measuring instrument

CHAPTER 8: RADIATION CHAPTER 8: RADIATION AND PROPAGATION OF AND PROPAGATION OF WAVESWAVES

1. Indicated which one of the 1. Indicated which one of the following terms applies to following terms applies to troposcatter propagation:troposcatter propagation:

a. SIDsa. SIDs

b. Fadingb. Fading

c. Atmospheric stormsc. Atmospheric storms

d. Faraday Rotationd. Faraday Rotation

1. Indicated which one of the 1. Indicated which one of the following terms applies to following terms applies to troposcatter propagation:troposcatter propagation:

a. SIDsa. SIDs

b. Fadingb. Fading

c. Atmospheric stormsc. Atmospheric storms

d. Faraday Rotationd. Faraday Rotation

2. VLF waves are used for some 2. VLF waves are used for some types of services becausetypes of services because

a. of the low powers requireda. of the low powers required

b. the transmitting antennas are of b. the transmitting antennas are of convenient sizeconvenient size

c. they are very reliablec. they are very reliable

d. they penetrate the ionosphere d. they penetrate the ionosphere easilyeasily

2. VLF waves are used for some 2. VLF waves are used for some types of services becausetypes of services because

a. of the low powers requireda. of the low powers required

b. the transmitting antennas are of b. the transmitting antennas are of convenient sizeconvenient size

c. they are very reliablec. they are very reliable

d. they penetrate the ionosphere d. they penetrate the ionosphere easilyeasily

3. Indicate which of the following 3. Indicate which of the following frequencies cannot be used for frequencies cannot be used for reliable beyond the horizon reliable beyond the horizon terrestrial communication without terrestrial communication without repeatersrepeaters

a. 20KHza. 20KHzb. 15MHzb. 15MHzc. 900MHzc. 900MHzd. 12GHzd. 12GHz

3. Indicate which of the following 3. Indicate which of the following frequencies cannot be used for frequencies cannot be used for reliable beyond the horizon reliable beyond the horizon terrestrial communication without terrestrial communication without repeatersrepeaters

a. 20KHza. 20KHzb. 15MHzb. 15MHzc. 900MHzc. 900MHzd. 12GHzd. 12GHz

4. High frequency waves are4. High frequency waves are

a. absorbed by the F2 layera. absorbed by the F2 layer

b. reflected by the D layerb. reflected by the D layer

c. capable of use for long distance c. capable of use for long distance communication on the mooncommunication on the moon

d. affected by the solar cycled. affected by the solar cycle

4. High frequency waves are4. High frequency waves are

a. absorbed by the F2 layera. absorbed by the F2 layer

b. reflected by the D layerb. reflected by the D layer

c. capable of use for long distance c. capable of use for long distance communication on the mooncommunication on the moon

d. affected by the solar cycled. affected by the solar cycle

5. Distances near the skip distance 5. Distances near the skip distance should be used for the sky-wave should be used for the sky-wave propagationpropagation

a. to avoid tiltinga. to avoid tilting

b. to prevent sky-wave and upper ray b. to prevent sky-wave and upper ray interferenceinterference

c. to avoid the Faraday effectc. to avoid the Faraday effect

d. so as not to exceed the critical d. so as not to exceed the critical frequencyfrequency

5. Distances near the skip distance 5. Distances near the skip distance should be used for the sky-wave should be used for the sky-wave propagationpropagation

a. to avoid tiltinga. to avoid tilting

b. to prevent sky-wave and upper ray b. to prevent sky-wave and upper ray interferenceinterference

c. to avoid the Faraday effectc. to avoid the Faraday effect

d. so as not to exceed the critical d. so as not to exceed the critical frequencyfrequency

6. A ship-to-ship communication 6. A ship-to-ship communication system is plagued by fading. The system is plagued by fading. The best solution seems to be the use best solution seems to be the use ofof

a. a more directional antennasa. a more directional antennas

b. broadband antennasb. broadband antennas

c. frequency diversityc. frequency diversity

d. space diversityd. space diversity

6. A ship-to-ship communication 6. A ship-to-ship communication system is plagued by fading. The system is plagued by fading. The best solution seems to be the use best solution seems to be the use ofof

a. a more directional antennasa. a more directional antennas

b. broadband antennasb. broadband antennas

c. frequency diversityc. frequency diversity

d. space diversityd. space diversity

7. A range of microwave frequency 7. A range of microwave frequency more easily passed by the more easily passed by the atmosphere than the other is atmosphere than the other is called acalled a

a. windowa. window

b. critical frequencyb. critical frequency

c. gyro frequency rangec. gyro frequency range

d. Resonance in the atmosphered. Resonance in the atmosphere

7. A range of microwave frequency 7. A range of microwave frequency more easily passed by the more easily passed by the atmosphere than the other is atmosphere than the other is called acalled a

a. windowa. window

b. critical frequencyb. critical frequency

c. gyro frequency rangec. gyro frequency range

d. Resonance in the atmosphered. Resonance in the atmosphere

8. Frequencies in the UHF range 8. Frequencies in the UHF range normally propagate by means ofnormally propagate by means of

a. ground wavesa. ground waves

b. sky wavesb. sky waves

c. surface wavesc. surface waves

d. space wavesd. space waves

8. Frequencies in the UHF range 8. Frequencies in the UHF range normally propagate by means ofnormally propagate by means of

a. ground wavesa. ground waves

b. sky wavesb. sky waves

c. surface wavesc. surface waves

d. space wavesd. space waves

9. Tropospheric scatter is used with 9. Tropospheric scatter is used with frequencies in the following rangefrequencies in the following range

a. HFa. HF

b. VHFb. VHF

c. UHFc. UHF

d. VLFd. VLF

9. Tropospheric scatter is used with 9. Tropospheric scatter is used with frequencies in the following rangefrequencies in the following range

a. HFa. HF

b. VHFb. VHF

c. UHFc. UHF

d. VLFd. VLF

10. The ground wave eventually 10. The ground wave eventually disappears, as one moves away disappears, as one moves away from the transmitter, because offrom the transmitter, because of

a. interference from the sky wavea. interference from the sky waveb. loss of line of sight conditionsb. loss of line of sight conditionsc. maximum single hop distance c. maximum single hop distance

limitationslimitationsd. tiltingd. tilting

10. The ground wave eventually 10. The ground wave eventually disappears, as one moves away disappears, as one moves away from the transmitter, because offrom the transmitter, because of

a. interference from the sky wavea. interference from the sky waveb. loss of line of sight conditionsb. loss of line of sight conditionsc. maximum single hop distance c. maximum single hop distance

limitationslimitationsd. tiltingd. tilting

11. In electromagnetic waves, 11. In electromagnetic waves, polarizationpolarization

a. is caused by reflectiona. is caused by reflection

b. is due to the transverse nature of the b. is due to the transverse nature of the waveswaves

c. results from the longitudinal nature of c. results from the longitudinal nature of waveswaves

d. is always vertical in an isotropic d. is always vertical in an isotropic antennaantenna

11. In electromagnetic waves, 11. In electromagnetic waves, polarizationpolarization

a. is caused by reflectiona. is caused by reflection

b. is due to the transverse nature of the b. is due to the transverse nature of the waveswaves

c. results from the longitudinal nature of c. results from the longitudinal nature of waveswaves

d. is always vertical in an isotropic d. is always vertical in an isotropic antennaantenna

12. As electromagnetic waves 12. As electromagnetic waves travel in free space, one the travel in free space, one the following can happen to them:following can happen to them:

a. absorptiona. absorption

b. attenuationb. attenuation

c. refractionc. refraction

d. reflectiond. reflection

12. As electromagnetic waves 12. As electromagnetic waves travel in free space, one the travel in free space, one the following can happen to them:following can happen to them:

a. absorptiona. absorption

b. attenuationb. attenuation

c. refractionc. refraction

d. reflectiond. reflection

13. The absorption of radio waves by 13. The absorption of radio waves by the atmosphere depends onthe atmosphere depends on

a. their frequencya. their frequency

b. their distance from the b. their distance from the transmittertransmitter

c. the polarization of the wavesc. the polarization of the waves

d. the polarization of the atmosphered. the polarization of the atmosphere

13. The absorption of radio waves by 13. The absorption of radio waves by the atmosphere depends onthe atmosphere depends on

a. their frequencya. their frequency

b. their distance from the b. their distance from the transmittertransmitter

c. the polarization of the wavesc. the polarization of the waves

d. the polarization of the atmosphered. the polarization of the atmosphere

14. Electromagnetic waves are refracted 14. Electromagnetic waves are refracted when theywhen they

a. pass into a medium of different a. pass into a medium of different dielectric constantdielectric constant

b. are polarized at right angles to the b. are polarized at right angles to the direction of propagationdirection of propagation

c. encounter a perfectly conducting c. encounter a perfectly conducting surfacesurface

d. pass through small slot in a conducting d. pass through small slot in a conducting planeplane

14. Electromagnetic waves are refracted 14. Electromagnetic waves are refracted when theywhen they

a. pass into a medium of different a. pass into a medium of different dielectric constantdielectric constant

b. are polarized at right angles to the b. are polarized at right angles to the direction of propagationdirection of propagation

c. encounter a perfectly conducting c. encounter a perfectly conducting surfacesurface

d. pass through small slot in a conducting d. pass through small slot in a conducting planeplane

15. Diffraction of electromagnetic wave15. Diffraction of electromagnetic wave

a. is caused by reflections from the a. is caused by reflections from the groundground

b. arises only with the spherical wave b. arises only with the spherical wave frontsfronts

c. will occur when the waves pass c. will occur when the waves pass through a large slotthrough a large slot

d. may occur around the edge of a sharp d. may occur around the edge of a sharp obstacleobstacle

15. Diffraction of electromagnetic wave15. Diffraction of electromagnetic wave

a. is caused by reflections from the a. is caused by reflections from the groundground

b. arises only with the spherical wave b. arises only with the spherical wave frontsfronts

c. will occur when the waves pass c. will occur when the waves pass through a large slotthrough a large slot

d. may occur around the edge of a sharp d. may occur around the edge of a sharp obstacleobstacle

16. When microwave signals follow 16. When microwave signals follow the curvature of the earth, this is the curvature of the earth, this is known asknown as

a. the Faraday effecta. the Faraday effect

b. ductingb. ducting

c. troposheric scatterc. troposheric scatter

d. ionospheric reflectionsd. ionospheric reflections

16. When microwave signals follow 16. When microwave signals follow the curvature of the earth, this is the curvature of the earth, this is known asknown as

a. the Faraday effecta. the Faraday effect

b. ductingb. ducting

c. troposheric scatterc. troposheric scatter

d. ionospheric reflectionsd. ionospheric reflections

17. Helical antennas are often used 17. Helical antennas are often used for satellite tracking at VHF for satellite tracking at VHF because ofbecause of

a. troposcattera. troposcatter

b. superrefractionb. superrefraction

c. ionospheric refractionc. ionospheric refraction

d. the Faraday effectd. the Faraday effect

17. Helical antennas are often used 17. Helical antennas are often used for satellite tracking at VHF for satellite tracking at VHF because ofbecause of

a. troposcattera. troposcatter

b. superrefractionb. superrefraction

c. ionospheric refractionc. ionospheric refraction

d. the Faraday effectd. the Faraday effect

CHAPTER 9: CHAPTER 9: ANTENNASANTENNAS

1. An ungrounded antenna near the 1. An ungrounded antenna near the groundground

a. acts a single antenna of twice a. acts a single antenna of twice the heightthe height

b. is unlikely need an earth matb. is unlikely need an earth mat

c. acts as an antenna arrayc. acts as an antenna array

d. must be horizontally polarizedd. must be horizontally polarized

1. An ungrounded antenna near the 1. An ungrounded antenna near the groundground

a. acts a single antenna of twice a. acts a single antenna of twice the heightthe height

b. is unlikely need an earth matb. is unlikely need an earth mat

c. acts as an antenna arrayc. acts as an antenna array

d. must be horizontally polarizedd. must be horizontally polarized

2. One of the following consist of 2. One of the following consist of non resonant antennanon resonant antenna

a. rhombic antennaa. rhombic antenna

b. folded dipoleb. folded dipole

c. end fire arrayc. end fire array

d. broadside arrayd. broadside array

2. One of the following consist of 2. One of the following consist of non resonant antennanon resonant antenna

a. rhombic antennaa. rhombic antenna

b. folded dipoleb. folded dipole

c. end fire arrayc. end fire array

d. broadside arrayd. broadside array

3. One of the following is very 3. One of the following is very useful as a multiband HF useful as a multiband HF receiving antenna. This is thereceiving antenna. This is the

a. conical horna. conical horn

b. folded dipoleb. folded dipole

c. log-periodicc. log-periodic

d. square loopd. square loop

3. One of the following is very 3. One of the following is very useful as a multiband HF useful as a multiband HF receiving antenna. This is thereceiving antenna. This is the

a. conical horna. conical horn

b. folded dipoleb. folded dipole

c. log-periodicc. log-periodic

d. square loopd. square loop

4. Which of the following antenna is 4. Which of the following antenna is best excited from a waveguide?best excited from a waveguide?

a. biconicala. biconical

b. hornb. horn

c. helicalc. helical

d. disconed. discone

4. Which of the following antenna is 4. Which of the following antenna is best excited from a waveguide?best excited from a waveguide?

a. biconicala. biconical

b. hornb. horn

c. helicalc. helical

d. disconed. discone

5. Indicate which of the following 5. Indicate which of the following reasons for using a counter poise with reasons for using a counter poise with antenna is falseantenna is false

a. impossibility of a good ground a. impossibility of a good ground connectionconnection

b. protection of personnel working b. protection of personnel working undergroundunderground

c. provision of an earth for the antennac. provision of an earth for the antenna

d. rockiness of the ground itselfd. rockiness of the ground itself

5. Indicate which of the following 5. Indicate which of the following reasons for using a counter poise with reasons for using a counter poise with antenna is falseantenna is false

a. impossibility of a good ground a. impossibility of a good ground connectionconnection

b. protection of personnel working b. protection of personnel working undergroundunderground

c. provision of an earth for the antennac. provision of an earth for the antenna

d. rockiness of the ground itselfd. rockiness of the ground itself

6. One of the following is not a reason 6. One of the following is not a reason for the use of an antenna coupler:for the use of an antenna coupler:

a. to make the antenna look resistivea. to make the antenna look resistiveb. to provide the output amplifier b. to provide the output amplifier

with the correct load impedancewith the correct load impedancec. to discriminate against harmonicsc. to discriminate against harmonicsd. to prevent reradation of the local d. to prevent reradation of the local

oscillatoroscillator

6. One of the following is not a reason 6. One of the following is not a reason for the use of an antenna coupler:for the use of an antenna coupler:

a. to make the antenna look resistivea. to make the antenna look resistiveb. to provide the output amplifier b. to provide the output amplifier

with the correct load impedancewith the correct load impedancec. to discriminate against harmonicsc. to discriminate against harmonicsd. to prevent reradation of the local d. to prevent reradation of the local

oscillatoroscillator

7. Indicate the antenna that is not 7. Indicate the antenna that is not wideband:wideband:

a. Disconea. Discone

b. Folded dipoleb. Folded dipole

c. Helicalc. Helical

d. Marconid. Marconi

7. Indicate the antenna that is not 7. Indicate the antenna that is not wideband:wideband:

a. Disconea. Discone

b. Folded dipoleb. Folded dipole

c. Helicalc. Helical

d. Marconid. Marconi

8. Indicate which of the following reasons 8. Indicate which of the following reasons for use of an earth mat with antennas is for use of an earth mat with antennas is false:false:

a. impossibility of a good ground connectiona. impossibility of a good ground connection

b. provision of an earth for the antennab. provision of an earth for the antenna

c. protection of personnel working c. protection of personnel working underneathunderneath

d. improvement of radiation pattern of the d. improvement of radiation pattern of the antennaantenna

8. Indicate which of the following reasons 8. Indicate which of the following reasons for use of an earth mat with antennas is for use of an earth mat with antennas is false:false:

a. impossibility of a good ground connectiona. impossibility of a good ground connection

b. provision of an earth for the antennab. provision of an earth for the antenna

c. protection of personnel working c. protection of personnel working underneathunderneath

d. improvement of radiation pattern of the d. improvement of radiation pattern of the antennaantenna

9. Which one of the following terms 9. Which one of the following terms does not apply the yagi-uda does not apply the yagi-uda array?array?

a. good bandwidtha. good bandwidth

b. parasitic elementsb. parasitic elements

c. folded dipolec. folded dipole

d. high gaind. high gain

9. Which one of the following terms 9. Which one of the following terms does not apply the yagi-uda does not apply the yagi-uda array?array?

a. good bandwidtha. good bandwidth

b. parasitic elementsb. parasitic elements

c. folded dipolec. folded dipole

d. high gaind. high gain

10. An antenna that is circularly 10. An antenna that is circularly polarized is thepolarized is the

a. helicala. helical

b. small circular loopb. small circular loop

c. parabolic reflectorc. parabolic reflector

d. yagi–udad. yagi–uda

10. An antenna that is circularly 10. An antenna that is circularly polarized is thepolarized is the

a. helicala. helical

b. small circular loopb. small circular loop

c. parabolic reflectorc. parabolic reflector

d. yagi–udad. yagi–uda

11. The standard reference 11. The standard reference antenna for the directive gain is antenna for the directive gain is thethe

a. infinitesimal dipolea. infinitesimal dipole

b. isotropic antennab. isotropic antenna

c. elementary doubletc. elementary doublet

d. half wave dipoled. half wave dipole

11. The standard reference 11. The standard reference antenna for the directive gain is antenna for the directive gain is thethe

a. infinitesimal dipolea. infinitesimal dipole

b. isotropic antennab. isotropic antenna

c. elementary doubletc. elementary doublet

d. half wave dipoled. half wave dipole

12. Top loading is sometimes used 12. Top loading is sometimes used with an antenna in order to with an antenna in order to increase itsincrease its

a. effective heighta. effective height

b. bandwidthb. bandwidth

c. beam widthc. beam width

d. input capacitanced. input capacitance

12. Top loading is sometimes used 12. Top loading is sometimes used with an antenna in order to with an antenna in order to increase itsincrease its

a. effective heighta. effective height

b. bandwidthb. bandwidth

c. beam widthc. beam width

d. input capacitanced. input capacitance

13. Cassegrain feed is used with a 13. Cassegrain feed is used with a parabolic reflector toparabolic reflector to

a. increase the gain of the systema. increase the gain of the systemb. increase the beam width of the b. increase the beam width of the

systemsystemc. reduce the size of the main c. reduce the size of the main

reflectorreflectord. allow the feed to be placed at a d. allow the feed to be placed at a

convenient pointconvenient point

13. Cassegrain feed is used with a 13. Cassegrain feed is used with a parabolic reflector toparabolic reflector to

a. increase the gain of the systema. increase the gain of the systemb. increase the beam width of the b. increase the beam width of the

systemsystemc. reduce the size of the main c. reduce the size of the main

reflectorreflectord. allow the feed to be placed at a d. allow the feed to be placed at a

convenient pointconvenient point

14. Zoning is used with a dielectric 14. Zoning is used with a dielectric antenna in order toantenna in order to

a. reduce the bulk of the lensa. reduce the bulk of the lens

b. increase the bandwidth of the lensb. increase the bandwidth of the lens

c. permit pin point focusingc. permit pin point focusing

d. correct the curvature of the wave d. correct the curvature of the wave front from a horn that is too shortfront from a horn that is too short

14. Zoning is used with a dielectric 14. Zoning is used with a dielectric antenna in order toantenna in order to

a. reduce the bulk of the lensa. reduce the bulk of the lens

b. increase the bandwidth of the lensb. increase the bandwidth of the lens

c. permit pin point focusingc. permit pin point focusing

d. correct the curvature of the wave d. correct the curvature of the wave front from a horn that is too shortfront from a horn that is too short

15. Helical antenna is used for 15. Helical antenna is used for satellite tracking because of itssatellite tracking because of its

a. circular polarizationa. circular polarization

b. maneuverabilityb. maneuverability

c. broad bandwidthc. broad bandwidth

d. good front to back ratiod. good front to back ratio

15. Helical antenna is used for 15. Helical antenna is used for satellite tracking because of itssatellite tracking because of its

a. circular polarizationa. circular polarization

b. maneuverabilityb. maneuverability

c. broad bandwidthc. broad bandwidth

d. good front to back ratiod. good front to back ratio

16. The discone antenna is16. The discone antenna is

a. a useful direction finding antennaa. a useful direction finding antenna

b. used as a radar receiving antennab. used as a radar receiving antenna

c. circularly polarized like other c. circularly polarized like other circular antennascircular antennas

d. useful as a UHF receiving antennad. useful as a UHF receiving antenna

16. The discone antenna is16. The discone antenna is

a. a useful direction finding antennaa. a useful direction finding antenna

b. used as a radar receiving antennab. used as a radar receiving antenna

c. circularly polarized like other c. circularly polarized like other circular antennascircular antennas

d. useful as a UHF receiving antennad. useful as a UHF receiving antenna

17. One of the following is not an 17. One of the following is not an omni directional antennaomni directional antenna

a. Half wave dipolea. Half wave dipole

b. Log periodicb. Log periodic

c. Disconec. Discone

d. Marconid. Marconi

17. One of the following is not an 17. One of the following is not an omni directional antennaomni directional antenna

a. Half wave dipolea. Half wave dipole

b. Log periodicb. Log periodic

c. Disconec. Discone

d. Marconid. Marconi

CHAPTER 10: CHAPTER 10: WAVEGUIDES, WAVEGUIDES, RESONATORS and RESONATORS and COMPONENTSCOMPONENTS

1. When electromagnetic waves are 1. When electromagnetic waves are propagated in a wave guidepropagated in a wave guide

a. they travel along the broader a. they travel along the broader walls of the guidewalls of the guide

b. they are reflected from the walls b. they are reflected from the walls but do not travel along thembut do not travel along them

c. they travel through the dielectric c. they travel through the dielectric without touching the wallswithout touching the walls

d. they travel along all four walls of d. they travel along all four walls of the waveguidethe waveguide

1. When electromagnetic waves are 1. When electromagnetic waves are propagated in a wave guidepropagated in a wave guide

a. they travel along the broader a. they travel along the broader walls of the guidewalls of the guide

b. they are reflected from the walls b. they are reflected from the walls but do not travel along thembut do not travel along them

c. they travel through the dielectric c. they travel through the dielectric without touching the wallswithout touching the walls

d. they travel along all four walls of d. they travel along all four walls of the waveguidethe waveguide

2. Waveguides are used mainly for 2. Waveguides are used mainly for microwave signals becausemicrowave signals because

a. the depend on the straight line a. the depend on the straight line propagation which applies to microwaves propagation which applies to microwaves onlyonly

b. losses would be to heavy at lower b. losses would be to heavy at lower frequenciesfrequencies

c. there are no generators powerful enough c. there are no generators powerful enough to excite them at lower frequenciesto excite them at lower frequencies

d. they would be too bulky at lower d. they would be too bulky at lower frequenciesfrequencies

2. Waveguides are used mainly for 2. Waveguides are used mainly for microwave signals becausemicrowave signals because

a. the depend on the straight line a. the depend on the straight line propagation which applies to microwaves propagation which applies to microwaves onlyonly

b. losses would be to heavy at lower b. losses would be to heavy at lower frequenciesfrequencies

c. there are no generators powerful enough c. there are no generators powerful enough to excite them at lower frequenciesto excite them at lower frequencies

d. they would be too bulky at lower d. they would be too bulky at lower frequenciesfrequencies

3. The wavelength of a wave in a waveguide3. The wavelength of a wave in a waveguide

a. is greater than in free spacea. is greater than in free space

b. depends only on the wave guide b. depends only on the wave guide dimensions and the free space dimensions and the free space wavelengthwavelength

c. is inversely proportional to the phase c. is inversely proportional to the phase velocityvelocity

d. is directly proportional to the group d. is directly proportional to the group velocityvelocity

3. The wavelength of a wave in a waveguide3. The wavelength of a wave in a waveguide

a. is greater than in free spacea. is greater than in free space

b. depends only on the wave guide b. depends only on the wave guide dimensions and the free space dimensions and the free space wavelengthwavelength

c. is inversely proportional to the phase c. is inversely proportional to the phase velocityvelocity

d. is directly proportional to the group d. is directly proportional to the group velocityvelocity

4. The main difference between the operation of 4. The main difference between the operation of transmission lines and wave guides is thattransmission lines and wave guides is that

a. the latter are not distributed, like transmission a. the latter are not distributed, like transmission lineslines

b. the former can use stubs and quarter wave b. the former can use stubs and quarter wave transformers, unlike the lattertransformers, unlike the latter

c. transmission lines use the principal mode of c. transmission lines use the principal mode of propagation, and therefore do not suffer from propagation, and therefore do not suffer from low frequency cut offlow frequency cut off

d. terms such as impedance matching and d. terms such as impedance matching and standing wave ration cannot be applied to standing wave ration cannot be applied to waveguideswaveguides

4. The main difference between the operation of 4. The main difference between the operation of transmission lines and wave guides is thattransmission lines and wave guides is that

a. the latter are not distributed, like transmission a. the latter are not distributed, like transmission lineslines

b. the former can use stubs and quarter wave b. the former can use stubs and quarter wave transformers, unlike the lattertransformers, unlike the latter

c. transmission lines use the principal mode of c. transmission lines use the principal mode of propagation, and therefore do not suffer from propagation, and therefore do not suffer from low frequency cut offlow frequency cut off

d. terms such as impedance matching and d. terms such as impedance matching and standing wave ration cannot be applied to standing wave ration cannot be applied to waveguideswaveguides

5. Compared with the equivalent 5. Compared with the equivalent transmission line, 3GHz transmission line, 3GHz waveguides (indicate the false waveguides (indicate the false statement)statement)

a. are less lossya. are less lossy

b. can carry high powersb. can carry high powers

c. are less bulkyc. are less bulky

d. have lower attenuationd. have lower attenuation

5. Compared with the equivalent 5. Compared with the equivalent transmission line, 3GHz transmission line, 3GHz waveguides (indicate the false waveguides (indicate the false statement)statement)

a. are less lossya. are less lossy

b. can carry high powersb. can carry high powers

c. are less bulkyc. are less bulky

d. have lower attenuationd. have lower attenuation

6. When a particular mode is excited 6. When a particular mode is excited in a waveguide, there appears an in a waveguide, there appears an extra electric component, in the extra electric component, in the direction of propagation. The direction of propagation. The resulting mode isresulting mode is

a. transverse-electrica. transverse-electricb. transverse-magneticb. transverse-magneticc. longitudinalc. longitudinald. transverse-electromagneticd. transverse-electromagnetic

6. When a particular mode is excited 6. When a particular mode is excited in a waveguide, there appears an in a waveguide, there appears an extra electric component, in the extra electric component, in the direction of propagation. The direction of propagation. The resulting mode isresulting mode is

a. transverse-electrica. transverse-electricb. transverse-magneticb. transverse-magneticc. longitudinalc. longitudinald. transverse-electromagneticd. transverse-electromagnetic

7. When electromagnetic waves are 7. When electromagnetic waves are reflected at an angle from a wall, their reflected at an angle from a wall, their wave length along the wall iswave length along the wall is

a. the same as in free spacea. the same as in free spaceb. the same as the wavelength b. the same as the wavelength

perpendicular to the wallperpendicular to the wallc. shortened because of the Doppler c. shortened because of the Doppler

effecteffectd. greater than in the actual direction of d. greater than in the actual direction of

propagationpropagation

7. When electromagnetic waves are 7. When electromagnetic waves are reflected at an angle from a wall, their reflected at an angle from a wall, their wave length along the wall iswave length along the wall is

a. the same as in free spacea. the same as in free spaceb. the same as the wavelength b. the same as the wavelength

perpendicular to the wallperpendicular to the wallc. shortened because of the Doppler c. shortened because of the Doppler

effecteffectd. greater than in the actual direction of d. greater than in the actual direction of

propagationpropagation

8. As a result of reflections from a plane 8. As a result of reflections from a plane conducting wall, electromagnetic conducting wall, electromagnetic waves require an apparent velocity waves require an apparent velocity greater than the velocity of light in greater than the velocity of light in space. This is calledspace. This is called

a. velocity of propagationa. velocity of propagation

b. normal velocityb. normal velocity

c. group velocityc. group velocity

d. phase velocityd. phase velocity

8. As a result of reflections from a plane 8. As a result of reflections from a plane conducting wall, electromagnetic conducting wall, electromagnetic waves require an apparent velocity waves require an apparent velocity greater than the velocity of light in greater than the velocity of light in space. This is calledspace. This is called

a. velocity of propagationa. velocity of propagation

b. normal velocityb. normal velocity

c. group velocityc. group velocity

d. phase velocityd. phase velocity

9. Indicate the false statement. When the 9. Indicate the false statement. When the free space wavelength of a signal equals free space wavelength of a signal equals the cutoff waveguide of the guidethe cutoff waveguide of the guide

a. the group velocity of the signal becomes a. the group velocity of the signal becomes zerozero

b. the phase velocity of the signal becomes b. the phase velocity of the signal becomes infiniteinfinite

c. the characteristic impedance of the guide c. the characteristic impedance of the guide becomes infinitebecomes infinite

d. the wavelength within the wave guide d. the wavelength within the wave guide becomes infinitebecomes infinite

9. Indicate the false statement. When the 9. Indicate the false statement. When the free space wavelength of a signal equals free space wavelength of a signal equals the cutoff waveguide of the guidethe cutoff waveguide of the guide

a. the group velocity of the signal becomes a. the group velocity of the signal becomes zerozero

b. the phase velocity of the signal becomes b. the phase velocity of the signal becomes infiniteinfinite

c. the characteristic impedance of the guide c. the characteristic impedance of the guide becomes infinitebecomes infinite

d. the wavelength within the wave guide d. the wavelength within the wave guide becomes infinitebecomes infinite

10. A signal propagated in a waveguide 10. A signal propagated in a waveguide has a full wave of electric intensity has a full wave of electric intensity change between the two further walls, change between the two further walls, and no component of the electric field and no component of the electric field in the direction of propagation. The in the direction of propagation. The mode ismode is

a. TE 1,1a. TE 1,1b. TE 1,0b. TE 1,0c. TM 2,2c. TM 2,2d. TE 2,0d. TE 2,0

10. A signal propagated in a waveguide 10. A signal propagated in a waveguide has a full wave of electric intensity has a full wave of electric intensity change between the two further walls, change between the two further walls, and no component of the electric field and no component of the electric field in the direction of propagation. The in the direction of propagation. The mode ismode is

a. TE 1,1a. TE 1,1b. TE 1,0b. TE 1,0c. TM 2,2c. TM 2,2d. TE 2,0d. TE 2,0

11. The dominant mode of propagation is 11. The dominant mode of propagation is preferred with rectangular waveguides preferred with rectangular waveguides because (false)because (false)

a. it leads to the smallest waveguide a. it leads to the smallest waveguide dimensionsdimensions

b. the resulting impedance can be b. the resulting impedance can be matched directly to coaxial linesmatched directly to coaxial lines

c. its is easier to excite than the other c. its is easier to excite than the other modesmodes

d. propagation of it without any spurious d. propagation of it without any spurious generation can be ensuredgeneration can be ensured

11. The dominant mode of propagation is 11. The dominant mode of propagation is preferred with rectangular waveguides preferred with rectangular waveguides because (false)because (false)

a. it leads to the smallest waveguide a. it leads to the smallest waveguide dimensionsdimensions

b. the resulting impedance can be b. the resulting impedance can be matched directly to coaxial linesmatched directly to coaxial lines

c. its is easier to excite than the other c. its is easier to excite than the other modesmodes

d. propagation of it without any spurious d. propagation of it without any spurious generation can be ensuredgeneration can be ensured

12. A choke flange may be used to 12. A choke flange may be used to couple two waveguidescouple two waveguides

a. to help in alignment of the waveguidesa. to help in alignment of the waveguides

b. because it is simplier than any other b. because it is simplier than any other joinjoin

c. to compensate for discontinuities at c. to compensate for discontinuities at the jointhe join

d. to increase the bandwidth of the d. to increase the bandwidth of the systemsystem

12. A choke flange may be used to 12. A choke flange may be used to couple two waveguidescouple two waveguides

a. to help in alignment of the waveguidesa. to help in alignment of the waveguides

b. because it is simplier than any other b. because it is simplier than any other joinjoin

c. to compensate for discontinuities at c. to compensate for discontinuities at the jointhe join

d. to increase the bandwidth of the d. to increase the bandwidth of the systemsystem

13. In order to couple two 13. In order to couple two generators to a waveguide generators to a waveguide system without coupling them to system without coupling them to each other, one could not use aeach other, one could not use a

a. rat racea. rat raceb. E – plane Tb. E – plane Tc. Hybrid ringc. Hybrid ringd. Magic Td. Magic T

13. In order to couple two 13. In order to couple two generators to a waveguide generators to a waveguide system without coupling them to system without coupling them to each other, one could not use aeach other, one could not use a

a. rat racea. rat raceb. E – plane Tb. E – plane Tc. Hybrid ringc. Hybrid ringd. Magic Td. Magic T

14. Which of the following 14. Which of the following waveguide tuning components is waveguide tuning components is not easily adjustable?not easily adjustable?

a. screwa. screw

b. stubb. stub

c. irisc. iris

d. plungerd. plunger

14. Which of the following 14. Which of the following waveguide tuning components is waveguide tuning components is not easily adjustable?not easily adjustable?

a. screwa. screw

b. stubb. stub

c. irisc. iris

d. plungerd. plunger

15. A piston attenuator is a15. A piston attenuator is a

a. vane attenuatora. vane attenuator

b. waveguide below cutoffb. waveguide below cutoff

c. mode filterc. mode filter

d. flap attenuatord. flap attenuator

15. A piston attenuator is a15. A piston attenuator is a

a. vane attenuatora. vane attenuator

b. waveguide below cutoffb. waveguide below cutoff

c. mode filterc. mode filter

d. flap attenuatord. flap attenuator

16. Cylindrical cavity resonators are 16. Cylindrical cavity resonators are not used with klystrons because they not used with klystrons because they havehave

a. a Q that is too lowa. a Q that is too lowb. a shape whose resonant frequency b. a shape whose resonant frequency

is too difficult to calculateis too difficult to calculatec. harmonically related resonant c. harmonically related resonant

frequenciesfrequenciesd. too heavy lossesd. too heavy losses

16. Cylindrical cavity resonators are 16. Cylindrical cavity resonators are not used with klystrons because they not used with klystrons because they havehave

a. a Q that is too lowa. a Q that is too lowb. a shape whose resonant frequency b. a shape whose resonant frequency

is too difficult to calculateis too difficult to calculatec. harmonically related resonant c. harmonically related resonant

frequenciesfrequenciesd. too heavy lossesd. too heavy losses

17. A directional coupler with three or 17. A directional coupler with three or more holes is sometimes used in more holes is sometimes used in preference to the two hole couplerpreference to the two hole coupler

a. because it is more efficienta. because it is more efficientb. to increase coupling of the signalb. to increase coupling of the signalc. to reduce spurious mode c. to reduce spurious mode

generationgenerationd. to increase the bandwidth of the d. to increase the bandwidth of the

systemsystem

17. A directional coupler with three or 17. A directional coupler with three or more holes is sometimes used in more holes is sometimes used in preference to the two hole couplerpreference to the two hole coupler

a. because it is more efficienta. because it is more efficientb. to increase coupling of the signalb. to increase coupling of the signalc. to reduce spurious mode c. to reduce spurious mode

generationgenerationd. to increase the bandwidth of the d. to increase the bandwidth of the

systemsystem

18. A ferrite is18. A ferrite is

a. a non conductor with magnetic a. a non conductor with magnetic propertiesproperties

b. an intermetallic compound with b. an intermetallic compound with particularly good conductivityparticularly good conductivity

c. an insulator which heavily attenuates c. an insulator which heavily attenuates magnetic fieldsmagnetic fields

d. a microwave semiconductor invented d. a microwave semiconductor invented by faradayby faraday

18. A ferrite is18. A ferrite is

a. a non conductor with magnetic a. a non conductor with magnetic propertiesproperties

b. an intermetallic compound with b. an intermetallic compound with particularly good conductivityparticularly good conductivity

c. an insulator which heavily attenuates c. an insulator which heavily attenuates magnetic fieldsmagnetic fields

d. a microwave semiconductor invented d. a microwave semiconductor invented by faradayby faraday

19. Manganese ferrite may be used 19. Manganese ferrite may be used as a (false)as a (false)

a. circulatora. circulator

b. isolatorb. isolator

c. garnetc. garnet

d. phase shifterd. phase shifter

19. Manganese ferrite may be used 19. Manganese ferrite may be used as a (false)as a (false)

a. circulatora. circulator

b. isolatorb. isolator

c. garnetc. garnet

d. phase shifterd. phase shifter

20. The maximum power that may 20. The maximum power that may be handled by a ferrite be handled by a ferrite component is limited by thecomponent is limited by the

a. curie temperaturea. curie temperature

b. saturation magnetizationb. saturation magnetization

c. line widthc. line width

d. gyromagnetic resonanced. gyromagnetic resonance

20. The maximum power that may 20. The maximum power that may be handled by a ferrite be handled by a ferrite component is limited by thecomponent is limited by the

a. curie temperaturea. curie temperature

b. saturation magnetizationb. saturation magnetization

c. line widthc. line width

d. gyromagnetic resonanced. gyromagnetic resonance

21. A PIN diode is21. A PIN diode is

a. a metal semiconductor point a. a metal semiconductor point contact diodecontact diode

b. a microwave mixer diodeb. a microwave mixer diode

c. often used as a microwave c. often used as a microwave detectordetector

d. suitable for the use as a d. suitable for the use as a microwave switchmicrowave switch

21. A PIN diode is21. A PIN diode is

a. a metal semiconductor point a. a metal semiconductor point contact diodecontact diode

b. a microwave mixer diodeb. a microwave mixer diode

c. often used as a microwave c. often used as a microwave detectordetector

d. suitable for the use as a d. suitable for the use as a microwave switchmicrowave switch

22. A duplexer is used22. A duplexer is useda. to couple two different antennas to a a. to couple two different antennas to a

transmitter with out mutual interferencetransmitter with out mutual interferenceb. to allow the one antenna to be used for b. to allow the one antenna to be used for

reception or transmission without mutual reception or transmission without mutual interferenceinterference

c. To prevent interference between two c. To prevent interference between two antennas when they are connected to a antennas when they are connected to a receiverreceiver

d. to increase the speed of the pulses in d. to increase the speed of the pulses in pulsed radarpulsed radar

22. A duplexer is used22. A duplexer is useda. to couple two different antennas to a a. to couple two different antennas to a

transmitter with out mutual interferencetransmitter with out mutual interferenceb. to allow the one antenna to be used for b. to allow the one antenna to be used for

reception or transmission without mutual reception or transmission without mutual interferenceinterference

c. To prevent interference between two c. To prevent interference between two antennas when they are connected to a antennas when they are connected to a receiverreceiver

d. to increase the speed of the pulses in d. to increase the speed of the pulses in pulsed radarpulsed radar

23. For some applications, circular 23. For some applications, circular waveguides may be preferred to waveguides may be preferred to rectangular ones because ofrectangular ones because of

a. smaller cross section needed at a. smaller cross section needed at any frequencyany frequency

b. lower attenuationb. lower attenuationc. freedom from spurious modesc. freedom from spurious modesd. rotation of polarizationd. rotation of polarization

23. For some applications, circular 23. For some applications, circular waveguides may be preferred to waveguides may be preferred to rectangular ones because ofrectangular ones because of

a. smaller cross section needed at a. smaller cross section needed at any frequencyany frequency

b. lower attenuationb. lower attenuationc. freedom from spurious modesc. freedom from spurious modesd. rotation of polarizationd. rotation of polarization

24. Indicate which of the following 24. Indicate which of the following cannot be followed by the word cannot be followed by the word “waveguide”:“waveguide”:

a. Ellipticala. Elliptical

b. Flexibleb. Flexible

c. Coaxialc. Coaxial

d. Ridgedd. Ridged

24. Indicate which of the following 24. Indicate which of the following cannot be followed by the word cannot be followed by the word “waveguide”:“waveguide”:

a. Ellipticala. Elliptical

b. Flexibleb. Flexible

c. Coaxialc. Coaxial

d. Ridgedd. Ridged

25. In order to reduce cross 25. In order to reduce cross sectional dimensions, the sectional dimensions, the waveguide to use iswaveguide to use is

a. circulara. circular

b. ridgedb. ridged

c. rectangularc. rectangular

d. flexibled. flexible

25. In order to reduce cross 25. In order to reduce cross sectional dimensions, the sectional dimensions, the waveguide to use iswaveguide to use is

a. circulara. circular

b. ridgedb. ridged

c. rectangularc. rectangular

d. flexibled. flexible

26. For low attenuation, the best 26. For low attenuation, the best transmission medium istransmission medium is

a. flexible waveguidea. flexible waveguide

b. ridged waveguideb. ridged waveguide

c. rectangular waveguidec. rectangular waveguide

d. coaxial lined. coaxial line

26. For low attenuation, the best 26. For low attenuation, the best transmission medium istransmission medium is

a. flexible waveguidea. flexible waveguide

b. ridged waveguideb. ridged waveguide

c. rectangular waveguidec. rectangular waveguide

d. coaxial lined. coaxial line

CHAPTER 11: CHAPTER 11: MICROWAVE TUBES MICROWAVE TUBES AND CIRCUITSAND CIRCUITS

1. A microwave tube amplifier uses 1. A microwave tube amplifier uses an axial magnetic field and a an axial magnetic field and a radial electric field. This is theradial electric field. This is the

a. reflex klystrona. reflex klystron

b. coaxial magnetronb. coaxial magnetron

c. traveling wave tube magnetronc. traveling wave tube magnetron

d. CFAd. CFA

1. A microwave tube amplifier uses 1. A microwave tube amplifier uses an axial magnetic field and a an axial magnetic field and a radial electric field. This is theradial electric field. This is the

a. reflex klystrona. reflex klystron

b. coaxial magnetronb. coaxial magnetron

c. traveling wave tube magnetronc. traveling wave tube magnetron

d. CFAd. CFA

2. One of the following is unlikely to 2. One of the following is unlikely to be used as a pulsed device. It is be used as a pulsed device. It is thethe

a. multicavitya. multicavity

b. BWOb. BWO

c. CFAc. CFA

d. TWTd. TWT

2. One of the following is unlikely to 2. One of the following is unlikely to be used as a pulsed device. It is be used as a pulsed device. It is thethe

a. multicavitya. multicavity

b. BWOb. BWO

c. CFAc. CFA

d. TWTd. TWT

3. One of the reasons why vacuum 3. One of the reasons why vacuum tubes eventually fail at microwave tubes eventually fail at microwave frequencies is that theirfrequencies is that their

a. noise figure increasesa. noise figure increasesb. transit time becomes to shortb. transit time becomes to shortc. shunt capacitive reactance becomes c. shunt capacitive reactance becomes

too largetoo larged. series inductive reactance becomes d. series inductive reactance becomes

too smalltoo small

3. One of the reasons why vacuum 3. One of the reasons why vacuum tubes eventually fail at microwave tubes eventually fail at microwave frequencies is that theirfrequencies is that their

a. noise figure increasesa. noise figure increasesb. transit time becomes to shortb. transit time becomes to shortc. shunt capacitive reactance becomes c. shunt capacitive reactance becomes

too largetoo larged. series inductive reactance becomes d. series inductive reactance becomes

too smalltoo small

4. Indicate the false statement. 4. Indicate the false statement. Transit time in microwave tubes Transit time in microwave tubes will be reduced ifwill be reduced if

a. the electrodes are brought closer a. the electrodes are brought closer togethertogether

b. a higher anode current is usedb. a higher anode current is usedc. multiple or coaxial leads are usedc. multiple or coaxial leads are usedd. the anode voltage is made largerd. the anode voltage is made larger

4. Indicate the false statement. 4. Indicate the false statement. Transit time in microwave tubes Transit time in microwave tubes will be reduced ifwill be reduced if

a. the electrodes are brought closer a. the electrodes are brought closer togethertogether

b. a higher anode current is usedb. a higher anode current is usedc. multiple or coaxial leads are usedc. multiple or coaxial leads are usedd. the anode voltage is made largerd. the anode voltage is made larger

5. The Multicavity klystron5. The Multicavity klystron

a. is not a good low level amplifier a. is not a good low level amplifier because of noisebecause of noise

b. has a high repeller voltage to ensure a b. has a high repeller voltage to ensure a rapid transit timerapid transit time

c. is not suitable for pulsed operationc. is not suitable for pulsed operation

d. needs a long transit time through the d. needs a long transit time through the buncher cavity to ensure current buncher cavity to ensure current modulationmodulation

5. The Multicavity klystron5. The Multicavity klystron

a. is not a good low level amplifier a. is not a good low level amplifier because of noisebecause of noise

b. has a high repeller voltage to ensure a b. has a high repeller voltage to ensure a rapid transit timerapid transit time

c. is not suitable for pulsed operationc. is not suitable for pulsed operation

d. needs a long transit time through the d. needs a long transit time through the buncher cavity to ensure current buncher cavity to ensure current modulationmodulation

6. Indicate the false statement. Klystron 6. Indicate the false statement. Klystron may use intermediate cavities tomay use intermediate cavities to

a. prevent the oscillations that occur in a. prevent the oscillations that occur in two cavity klystrontwo cavity klystron

b. increase the bandwidth of the deviceb. increase the bandwidth of the device

c. improve the power gainc. improve the power gain

d. increase the efficiency of the klystrond. increase the efficiency of the klystron

6. Indicate the false statement. Klystron 6. Indicate the false statement. Klystron may use intermediate cavities tomay use intermediate cavities to

a. prevent the oscillations that occur in a. prevent the oscillations that occur in two cavity klystrontwo cavity klystron

b. increase the bandwidth of the deviceb. increase the bandwidth of the device

c. improve the power gainc. improve the power gain

d. increase the efficiency of the klystrond. increase the efficiency of the klystron

7. The TWT is sometimes preferred 7. The TWT is sometimes preferred to the multicavity klystron to the multicavity klystron amplifier, because the formeramplifier, because the former

a. is more efficienta. is more efficient

b. has a greater bandwidthb. has a greater bandwidth

c. has a higher number of modesc. has a higher number of modes

d. produces a higher output powerd. produces a higher output power

7. The TWT is sometimes preferred 7. The TWT is sometimes preferred to the multicavity klystron to the multicavity klystron amplifier, because the formeramplifier, because the former

a. is more efficienta. is more efficient

b. has a greater bandwidthb. has a greater bandwidth

c. has a higher number of modesc. has a higher number of modes

d. produces a higher output powerd. produces a higher output power

8. The transit time in the repeller space of a 8. The transit time in the repeller space of a reflex klystron must be n + ¾ cycles to reflex klystron must be n + ¾ cycles to ensure thatensure that

a. electrons are accelerated by the gap a. electrons are accelerated by the gap voltages on their returnvoltages on their return

b. returning electron give energy to gap b. returning electron give energy to gap oscillationsoscillations

c. it is equal to the period of the cavity c. it is equal to the period of the cavity oscillationsoscillations

d. the repeller is not damaged by the striking d. the repeller is not damaged by the striking electronselectrons

8. The transit time in the repeller space of a 8. The transit time in the repeller space of a reflex klystron must be n + ¾ cycles to reflex klystron must be n + ¾ cycles to ensure thatensure that

a. electrons are accelerated by the gap a. electrons are accelerated by the gap voltages on their returnvoltages on their return

b. returning electron give energy to gap b. returning electron give energy to gap oscillationsoscillations

c. it is equal to the period of the cavity c. it is equal to the period of the cavity oscillationsoscillations

d. the repeller is not damaged by the striking d. the repeller is not damaged by the striking electronselectrons

9. The cavity magnetron uses 9. The cavity magnetron uses strapping tostrapping to

a. prevent mode jumpinga. prevent mode jumping

b. prevent cathode back heatingb. prevent cathode back heating

c. ensure bunchingc. ensure bunching

d. improve the phase focusing d. improve the phase focusing effecteffect

9. The cavity magnetron uses 9. The cavity magnetron uses strapping tostrapping to

a. prevent mode jumpinga. prevent mode jumping

b. prevent cathode back heatingb. prevent cathode back heating

c. ensure bunchingc. ensure bunching

d. improve the phase focusing d. improve the phase focusing effecteffect

10. Magnetic field is used in the cavity 10. Magnetic field is used in the cavity magnetron tomagnetron to

a. prevent anode current in absence of a. prevent anode current in absence of oscillationsoscillations

b. ensure that the oscillations are pulsedb. ensure that the oscillations are pulsedc. help in focusing the electron beam, c. help in focusing the electron beam,

thus preventing spreadingthus preventing spreadingd. ensure electrons will orbit around the d. ensure electrons will orbit around the

cathodecathode

10. Magnetic field is used in the cavity 10. Magnetic field is used in the cavity magnetron tomagnetron to

a. prevent anode current in absence of a. prevent anode current in absence of oscillationsoscillations

b. ensure that the oscillations are pulsedb. ensure that the oscillations are pulsedc. help in focusing the electron beam, c. help in focusing the electron beam,

thus preventing spreadingthus preventing spreadingd. ensure electrons will orbit around the d. ensure electrons will orbit around the

cathodecathode

11. To avoid difficulties with 11. To avoid difficulties with strapping at high frequencies, the strapping at high frequencies, the type of cavity structure used in the type of cavity structure used in the magnetron is themagnetron is the

a. hole and slota. hole and slot

b. slotb. slot

c. vanec. vane

d. rising sund. rising sun

11. To avoid difficulties with 11. To avoid difficulties with strapping at high frequencies, the strapping at high frequencies, the type of cavity structure used in the type of cavity structure used in the magnetron is themagnetron is the

a. hole and slota. hole and slot

b. slotb. slot

c. vanec. vane

d. rising sund. rising sun

12. The primary purpose of the 12. The primary purpose of the helix in a traveling wave tube is tohelix in a traveling wave tube is to

a. prevent the electron beam from a. prevent the electron beam from spreading in the long tubespreading in the long tube

b. reduce the axial velocity of the b. reduce the axial velocity of the RF fieldRF field

c. ensure broadband operationc. ensure broadband operationd. reduce noise figured. reduce noise figure

12. The primary purpose of the 12. The primary purpose of the helix in a traveling wave tube is tohelix in a traveling wave tube is to

a. prevent the electron beam from a. prevent the electron beam from spreading in the long tubespreading in the long tube

b. reduce the axial velocity of the b. reduce the axial velocity of the RF fieldRF field

c. ensure broadband operationc. ensure broadband operationd. reduce noise figured. reduce noise figure

13. The attenuator is used in the 13. The attenuator is used in the traveling wave tube totraveling wave tube to

a. help bunchinga. help bunching

b. prevent oscillationsb. prevent oscillations

c. prevent saturationsc. prevent saturations

d. increase gaind. increase gain

13. The attenuator is used in the 13. The attenuator is used in the traveling wave tube totraveling wave tube to

a. help bunchinga. help bunching

b. prevent oscillationsb. prevent oscillations

c. prevent saturationsc. prevent saturations

d. increase gaind. increase gain

14. Periodic permanent magnet 14. Periodic permanent magnet focusing is used with TWTs tofocusing is used with TWTs to

a. allow pulsed operationa. allow pulsed operation

b. improve electron bunchingb. improve electron bunching

c. avoid the bulk of an c. avoid the bulk of an electromagnetelectromagnet

d. allow coupled cavity operation at d. allow coupled cavity operation at highest frequencieshighest frequencies

14. Periodic permanent magnet 14. Periodic permanent magnet focusing is used with TWTs tofocusing is used with TWTs to

a. allow pulsed operationa. allow pulsed operation

b. improve electron bunchingb. improve electron bunching

c. avoid the bulk of an c. avoid the bulk of an electromagnetelectromagnet

d. allow coupled cavity operation at d. allow coupled cavity operation at highest frequencieshighest frequencies

15. The TWT is sometimes preferred 15. The TWT is sometimes preferred to the magnetron as a radar to the magnetron as a radar transmitter output tube because it transmitter output tube because it isis

a. capable of longer duty cyclea. capable of longer duty cycle

b. more efficient amplifierb. more efficient amplifier

c. more broadbandc. more broadband

d. less noisyd. less noisy

15. The TWT is sometimes preferred 15. The TWT is sometimes preferred to the magnetron as a radar to the magnetron as a radar transmitter output tube because it transmitter output tube because it isis

a. capable of longer duty cyclea. capable of longer duty cycle

b. more efficient amplifierb. more efficient amplifier

c. more broadbandc. more broadband

d. less noisyd. less noisy

16. Magnetron whose oscillating 16. Magnetron whose oscillating frequency is electronically frequency is electronically adjustable over a wide range is adjustable over a wide range is called acalled a

a. coaxial magnetrona. coaxial magnetron

b. dither-tuned amplifierb. dither-tuned amplifier

c. frequency- agile magnetronc. frequency- agile magnetron

d. VTMd. VTM

16. Magnetron whose oscillating 16. Magnetron whose oscillating frequency is electronically frequency is electronically adjustable over a wide range is adjustable over a wide range is called acalled a

a. coaxial magnetrona. coaxial magnetron

b. dither-tuned amplifierb. dither-tuned amplifier

c. frequency- agile magnetronc. frequency- agile magnetron

d. VTMd. VTM

17. Indicate which of the following 17. Indicate which of the following is not TWT slow rate structure:is not TWT slow rate structure:

a. periodic permanent magneta. periodic permanent magnet

b. coupled cavityb. coupled cavity

c. helixc. helix

d. ring bard. ring bar

17. Indicate which of the following 17. Indicate which of the following is not TWT slow rate structure:is not TWT slow rate structure:

a. periodic permanent magneta. periodic permanent magnet

b. coupled cavityb. coupled cavity

c. helixc. helix

d. ring bard. ring bar

18. The glass tube of a TWT may be 18. The glass tube of a TWT may be coated with aquadag tocoated with aquadag to

a. help focusinga. help focusing

b. provide attenuationb. provide attenuation

c. improve bunchingc. improve bunching

d. increase gaind. increase gain

18. The glass tube of a TWT may be 18. The glass tube of a TWT may be coated with aquadag tocoated with aquadag to

a. help focusinga. help focusing

b. provide attenuationb. provide attenuation

c. improve bunchingc. improve bunching

d. increase gaind. increase gain

19. Back ward wave oscillator is 19. Back ward wave oscillator is based on thebased on the

a. rising sun magnetrona. rising sun magnetron

b. crossed field amplifierb. crossed field amplifier

c. coaxial magnetronc. coaxial magnetron

d. traveling wave tubed. traveling wave tube

19. Back ward wave oscillator is 19. Back ward wave oscillator is based on thebased on the

a. rising sun magnetrona. rising sun magnetron

b. crossed field amplifierb. crossed field amplifier

c. coaxial magnetronc. coaxial magnetron

d. traveling wave tubed. traveling wave tube

CHAPTER 12: CHAPTER 12: SEMICONDUCTOR SEMICONDUCTOR MICROWAVE DEVICES MICROWAVE DEVICES ANDANDCIRCUITSCIRCUITS

1. Parametric amplifier must be 1. Parametric amplifier must be cooledcooled

a. because parametric amplification a. because parametric amplification generates a lot of heatgenerates a lot of heat

b. to increase bandwidthb. to increase bandwidth

c. because it cannot operate at room c. because it cannot operate at room temperaturetemperature

d. to improve the noise performanced. to improve the noise performance

1. Parametric amplifier must be 1. Parametric amplifier must be cooledcooled

a. because parametric amplification a. because parametric amplification generates a lot of heatgenerates a lot of heat

b. to increase bandwidthb. to increase bandwidth

c. because it cannot operate at room c. because it cannot operate at room temperaturetemperature

d. to improve the noise performanced. to improve the noise performance

2. Ruby maser amplifier must be 2. Ruby maser amplifier must be cooledcooled

a. because maser amplification a. because maser amplification generates a lot of heatgenerates a lot of heat

b. to increase bandwidthb. to increase bandwidth

c. because it cannot operate at room c. because it cannot operate at room temperaturetemperature

d. to improve the noise performanced. to improve the noise performance

2. Ruby maser amplifier must be 2. Ruby maser amplifier must be cooledcooled

a. because maser amplification a. because maser amplification generates a lot of heatgenerates a lot of heat

b. to increase bandwidthb. to increase bandwidth

c. because it cannot operate at room c. because it cannot operate at room temperaturetemperature

d. to improve the noise performanced. to improve the noise performance

3. Disadvantage of microstrip 3. Disadvantage of microstrip compared with stripline is that compared with stripline is that microstripmicrostrip

a. does not readily lend itself to a. does not readily lend itself to printed circuit techniquesprinted circuit techniques

b. is more likely to radiateb. is more likely to radiatec. is bulkierc. is bulkierd. is more expensive and complex to d. is more expensive and complex to

manufacturemanufacture

3. Disadvantage of microstrip 3. Disadvantage of microstrip compared with stripline is that compared with stripline is that microstripmicrostrip

a. does not readily lend itself to a. does not readily lend itself to printed circuit techniquesprinted circuit techniques

b. is more likely to radiateb. is more likely to radiatec. is bulkierc. is bulkierd. is more expensive and complex to d. is more expensive and complex to

manufacturemanufacture

4. The transmission system using 4. The transmission system using two ground planes istwo ground planes is

a. microstripa. microstrip

b. elliptical waveguideb. elliptical waveguide

c. parallel wire linec. parallel wire line

d. striplined. stripline

4. The transmission system using 4. The transmission system using two ground planes istwo ground planes is

a. microstripa. microstrip

b. elliptical waveguideb. elliptical waveguide

c. parallel wire linec. parallel wire line

d. striplined. stripline

5. Indicate the false statement. An 5. Indicate the false statement. An advantage of stripline over advantage of stripline over waveguides is itswaveguides is its

a. smaller bulka. smaller bulkb. greater bandwidthb. greater bandwidthc. higher power handling capabilityc. higher power handling capabilityd. greater compatibility with solid d. greater compatibility with solid

state devicesstate devices

5. Indicate the false statement. An 5. Indicate the false statement. An advantage of stripline over advantage of stripline over waveguides is itswaveguides is its

a. smaller bulka. smaller bulkb. greater bandwidthb. greater bandwidthc. higher power handling capabilityc. higher power handling capabilityd. greater compatibility with solid d. greater compatibility with solid

state devicesstate devices

6. Indicate the false statement. An 6. Indicate the false statement. An advantage of stripline over microstrip is advantage of stripline over microstrip is itsits

a. easier integration with semiconductor a. easier integration with semiconductor devicesdevices

b. lower tendency to radiateb. lower tendency to radiate

c. higher isolation between adjacent c. higher isolation between adjacent circuitscircuits

d. higher Qd. higher Q

6. Indicate the false statement. An 6. Indicate the false statement. An advantage of stripline over microstrip is advantage of stripline over microstrip is itsits

a. easier integration with semiconductor a. easier integration with semiconductor devicesdevices

b. lower tendency to radiateb. lower tendency to radiate

c. higher isolation between adjacent c. higher isolation between adjacent circuitscircuits

d. higher Qd. higher Q

7. Surface acoustic waves 7. Surface acoustic waves propagate inpropagate in

a. gallium arsenidea. gallium arsenide

b. indium phosphideb. indium phosphide

c. striplinec. stripline

d. quartz crystald. quartz crystal

7. Surface acoustic waves 7. Surface acoustic waves propagate inpropagate in

a. gallium arsenidea. gallium arsenide

b. indium phosphideb. indium phosphide

c. striplinec. stripline

d. quartz crystald. quartz crystal

8. SAW devices may be used as8. SAW devices may be used as

a. transmission media like striplinea. transmission media like stripline

b. filtersb. filters

c. UHF amplifiersc. UHF amplifiers

d. Oscillators at millimeter d. Oscillators at millimeter frequenciesfrequencies

8. SAW devices may be used as8. SAW devices may be used as

a. transmission media like striplinea. transmission media like stripline

b. filtersb. filters

c. UHF amplifiersc. UHF amplifiers

d. Oscillators at millimeter d. Oscillators at millimeter frequenciesfrequencies

9. Indicate the false statement. FETs 9. Indicate the false statement. FETs are preferred to bipolar transistor are preferred to bipolar transistor at the high frequencies because at the high frequencies because theythey

a. are less noisya. are less noisyb. lend themselves more readily to b. lend themselves more readily to

integrationintegrationc. are capable of higher efficienciesc. are capable of higher efficienciesd. can provide higher gainsd. can provide higher gains

9. Indicate the false statement. FETs 9. Indicate the false statement. FETs are preferred to bipolar transistor are preferred to bipolar transistor at the high frequencies because at the high frequencies because theythey

a. are less noisya. are less noisyb. lend themselves more readily to b. lend themselves more readily to

integrationintegrationc. are capable of higher efficienciesc. are capable of higher efficienciesd. can provide higher gainsd. can provide higher gains

10. For best low level noise 10. For best low level noise performance in the X-band, an performance in the X-band, an amplifier should useamplifier should use

a. a bipolar transistora. a bipolar transistor

b. a Gunn diodeb. a Gunn diode

c. a step-recovery diodec. a step-recovery diode

d. an IMPATT dioded. an IMPATT diode

10. For best low level noise 10. For best low level noise performance in the X-band, an performance in the X-band, an amplifier should useamplifier should use

a. a bipolar transistora. a bipolar transistor

b. a Gunn diodeb. a Gunn diode

c. a step-recovery diodec. a step-recovery diode

d. an IMPATT dioded. an IMPATT diode

11. The biggest advantage of the 11. The biggest advantage of the TRAPATT diode over the IMPATT TRAPATT diode over the IMPATT diode is itsdiode is its

a. low noisea. low noiseb. higher efficiencyb. higher efficiencyc. ability to operate at higher c. ability to operate at higher

frequenciesfrequenciesd. lesser sensitivity to harmonicsd. lesser sensitivity to harmonics

11. The biggest advantage of the 11. The biggest advantage of the TRAPATT diode over the IMPATT TRAPATT diode over the IMPATT diode is itsdiode is its

a. low noisea. low noiseb. higher efficiencyb. higher efficiencyc. ability to operate at higher c. ability to operate at higher

frequenciesfrequenciesd. lesser sensitivity to harmonicsd. lesser sensitivity to harmonics

12. Indicate which of the following 12. Indicate which of the following diodes will produce the highest diodes will produce the highest pulsed power outputpulsed power output

a. Varactora. Varactor

b. Gunnb. Gunn

c. Schottky barrierc. Schottky barrier

d. RIMPATTd. RIMPATT

12. Indicate which of the following 12. Indicate which of the following diodes will produce the highest diodes will produce the highest pulsed power outputpulsed power output

a. Varactora. Varactor

b. Gunnb. Gunn

c. Schottky barrierc. Schottky barrier

d. RIMPATTd. RIMPATT

13. Indicate which of the following 13. Indicate which of the following diodes does not use negative diodes does not use negative resistance in its operation:resistance in its operation:

a. Backwarda. Backward

b. Gunnb. Gunn

c. IMPATTc. IMPATT

d. Tunneld. Tunnel

13. Indicate which of the following 13. Indicate which of the following diodes does not use negative diodes does not use negative resistance in its operation:resistance in its operation:

a. Backwarda. Backward

b. Gunnb. Gunn

c. IMPATTc. IMPATT

d. Tunneld. Tunnel

14. One of the following is not used 14. One of the following is not used as a microwave mixer or detector.as a microwave mixer or detector.

a. crystal diodea. crystal diode

b. schottky barrier diodeb. schottky barrier diode

c. backward diodec. backward diode

d. PIN dioded. PIN diode

14. One of the following is not used 14. One of the following is not used as a microwave mixer or detector.as a microwave mixer or detector.

a. crystal diodea. crystal diode

b. schottky barrier diodeb. schottky barrier diode

c. backward diodec. backward diode

d. PIN dioded. PIN diode

15. One of the following microwave 15. One of the following microwave diodes is suitable for very low diodes is suitable for very low power oscillations only:power oscillations only:

a. tunnela. tunnel

b. avalancheb. avalanche

c. Gunnc. Gunn

d. IMPATTd. IMPATT

15. One of the following microwave 15. One of the following microwave diodes is suitable for very low diodes is suitable for very low power oscillations only:power oscillations only:

a. tunnela. tunnel

b. avalancheb. avalanche

c. Gunnc. Gunn

d. IMPATTd. IMPATT

16. The transferred electron bulk 16. The transferred electron bulk effect occurs ineffect occurs in

a. germaniuma. germanium

b. gallium arsenideb. gallium arsenide

c. siliconc. silicon

d. metal semiconductor, junctionsd. metal semiconductor, junctions

16. The transferred electron bulk 16. The transferred electron bulk effect occurs ineffect occurs in

a. germaniuma. germanium

b. gallium arsenideb. gallium arsenide

c. siliconc. silicon

d. metal semiconductor, junctionsd. metal semiconductor, junctions

17. The gain bandwidth frequency of 17. The gain bandwidth frequency of a microwave transistor, fa microwave transistor, fTT, is the , is the frequency at which thefrequency at which the

a. alpha of the transistor falls by 3dBa. alpha of the transistor falls by 3dBb. beta of the transistor falls by 3dBb. beta of the transistor falls by 3dBc. power gain of the transistor falls c. power gain of the transistor falls

to unityto unityd. beta of the transistor falls to unityd. beta of the transistor falls to unity

17. The gain bandwidth frequency of 17. The gain bandwidth frequency of a microwave transistor, fa microwave transistor, fTT, is the , is the frequency at which thefrequency at which the

a. alpha of the transistor falls by 3dBa. alpha of the transistor falls by 3dBb. beta of the transistor falls by 3dBb. beta of the transistor falls by 3dBc. power gain of the transistor falls c. power gain of the transistor falls

to unityto unityd. beta of the transistor falls to unityd. beta of the transistor falls to unity

18. For microwave transistor to 18. For microwave transistor to operate at the high frequencies, operate at the high frequencies, the (false)the (false)

a. collector voltage must be largea. collector voltage must be large

b. collector current must be highb. collector current must be high

c. base should be thinc. base should be thin

d. emitter area must be larged. emitter area must be large

18. For microwave transistor to 18. For microwave transistor to operate at the high frequencies, operate at the high frequencies, the (false)the (false)

a. collector voltage must be largea. collector voltage must be large

b. collector current must be highb. collector current must be high

c. base should be thinc. base should be thin

d. emitter area must be larged. emitter area must be large

19. Varactor diode may be useful at 19. Varactor diode may be useful at microwave frequencies (false)microwave frequencies (false)

a. for electronic tuninga. for electronic tuning

b. for frequency multiplicationb. for frequency multiplication

c. as an oscillatorc. as an oscillator

d. as a parametric amplifierd. as a parametric amplifier

19. Varactor diode may be useful at 19. Varactor diode may be useful at microwave frequencies (false)microwave frequencies (false)

a. for electronic tuninga. for electronic tuning

b. for frequency multiplicationb. for frequency multiplication

c. as an oscillatorc. as an oscillator

d. as a parametric amplifierd. as a parametric amplifier

20. If high order frequency multiplication 20. If high order frequency multiplication is required from a diode multiplier,is required from a diode multiplier,

a. the resistive cuttoff frequency must be a. the resistive cuttoff frequency must be highhigh

b. a small value of base resistance is b. a small value of base resistance is requiredrequired

c. a step recovery diode must be usedc. a step recovery diode must be used

d. a large range of capacitance variation is d. a large range of capacitance variation is neededneeded

20. If high order frequency multiplication 20. If high order frequency multiplication is required from a diode multiplier,is required from a diode multiplier,

a. the resistive cuttoff frequency must be a. the resistive cuttoff frequency must be highhigh

b. a small value of base resistance is b. a small value of base resistance is requiredrequired

c. a step recovery diode must be usedc. a step recovery diode must be used

d. a large range of capacitance variation is d. a large range of capacitance variation is neededneeded

21. Parametric amplifier has an input 21. Parametric amplifier has an input and output frequency of 2.25GHz and output frequency of 2.25GHz and is pumped at 4.5GHz. It is aand is pumped at 4.5GHz. It is a

a. traveling wave amplifiera. traveling wave amplifier

b. degenerative amplifierb. degenerative amplifier

c. lower sideband up converterc. lower sideband up converter

d. upper sideband up converterd. upper sideband up converter

21. Parametric amplifier has an input 21. Parametric amplifier has an input and output frequency of 2.25GHz and output frequency of 2.25GHz and is pumped at 4.5GHz. It is aand is pumped at 4.5GHz. It is a

a. traveling wave amplifiera. traveling wave amplifier

b. degenerative amplifierb. degenerative amplifier

c. lower sideband up converterc. lower sideband up converter

d. upper sideband up converterd. upper sideband up converter

22. Non degenerate parametric 22. Non degenerate parametric amplifier has an input frequency Fi amplifier has an input frequency Fi and a pump frequency Fp. The and a pump frequency Fp. The idler frequency isidler frequency is

a. Fia. Fi

b. 2Fib. 2Fi

c. Fi – Fpc. Fi – Fp

d. Fp – Fid. Fp – Fi

22. Non degenerate parametric 22. Non degenerate parametric amplifier has an input frequency Fi amplifier has an input frequency Fi and a pump frequency Fp. The and a pump frequency Fp. The idler frequency isidler frequency is

a. Fia. Fi

b. 2Fib. 2Fi

c. Fi – Fpc. Fi – Fp

d. Fp – Fid. Fp – Fi

23. Traveling wave parametric 23. Traveling wave parametric amplifiers are used toamplifiers are used to

a. provide a greater gaina. provide a greater gain

b. reduce the number of varactor b. reduce the number of varactor diodes requireddiodes required

c. avoid the need for coolingc. avoid the need for cooling

d. provide a greater bandwidthd. provide a greater bandwidth

23. Traveling wave parametric 23. Traveling wave parametric amplifiers are used toamplifiers are used to

a. provide a greater gaina. provide a greater gain

b. reduce the number of varactor b. reduce the number of varactor diodes requireddiodes required

c. avoid the need for coolingc. avoid the need for cooling

d. provide a greater bandwidthd. provide a greater bandwidth

24. A parametric amplifier sometimes 24. A parametric amplifier sometimes uses a circulator touses a circulator to

a. prevent noise feedbacka. prevent noise feedback

b. allow the antenna to be used b. allow the antenna to be used simultaneously for transmission and simultaneously for transmission and receptionreception

c. separate the signal and idler c. separate the signal and idler frequenciesfrequencies

d. permit more efficient pumpingd. permit more efficient pumping

24. A parametric amplifier sometimes 24. A parametric amplifier sometimes uses a circulator touses a circulator to

a. prevent noise feedbacka. prevent noise feedback

b. allow the antenna to be used b. allow the antenna to be used simultaneously for transmission and simultaneously for transmission and receptionreception

c. separate the signal and idler c. separate the signal and idler frequenciesfrequencies

d. permit more efficient pumpingd. permit more efficient pumping

25. The non degenerate one port 25. The non degenerate one port parametric amplifier should have a high parametric amplifier should have a high ratio of pump to signal frequency ratio of pump to signal frequency because thisbecause this

a. permits satisfactory high frequency a. permits satisfactory high frequency operationoperation

b. yields a low noise figureb. yields a low noise figurec. reduces the pump power requiredc. reduces the pump power requiredd. permits satisfactory low frequency d. permits satisfactory low frequency

operationoperation

25. The non degenerate one port 25. The non degenerate one port parametric amplifier should have a high parametric amplifier should have a high ratio of pump to signal frequency ratio of pump to signal frequency because thisbecause this

a. permits satisfactory high frequency a. permits satisfactory high frequency operationoperation

b. yields a low noise figureb. yields a low noise figurec. reduces the pump power requiredc. reduces the pump power requiredd. permits satisfactory low frequency d. permits satisfactory low frequency

operationoperation

26. Tunnel diode26. Tunnel diodea. has a tiny hole through its center to a. has a tiny hole through its center to

facilitate tunnelingfacilitate tunnelingb. is a point contact diode with a very b. is a point contact diode with a very

high reverse resistancehigh reverse resistancec. uses a high doping level to provide c. uses a high doping level to provide

a narrow junctiona narrow junctiond. works by quantum tunneling d. works by quantum tunneling

exhibited by gallium arsenide onlyexhibited by gallium arsenide only

26. Tunnel diode26. Tunnel diodea. has a tiny hole through its center to a. has a tiny hole through its center to

facilitate tunnelingfacilitate tunnelingb. is a point contact diode with a very b. is a point contact diode with a very

high reverse resistancehigh reverse resistancec. uses a high doping level to provide c. uses a high doping level to provide

a narrow junctiona narrow junctiond. works by quantum tunneling d. works by quantum tunneling

exhibited by gallium arsenide onlyexhibited by gallium arsenide only

27. A tunnel diode is loosely 27. A tunnel diode is loosely coupled to its cavity in order tocoupled to its cavity in order to

a. increase the frequency stabilitya. increase the frequency stabilityb. increase the availability negative b. increase the availability negative

resistanceresistancec. facilitate tunningc. facilitate tunningd. allow operation at the highest d. allow operation at the highest

frequenciesfrequencies

27. A tunnel diode is loosely 27. A tunnel diode is loosely coupled to its cavity in order tocoupled to its cavity in order to

a. increase the frequency stabilitya. increase the frequency stabilityb. increase the availability negative b. increase the availability negative

resistanceresistancec. facilitate tunningc. facilitate tunningd. allow operation at the highest d. allow operation at the highest

frequenciesfrequencies

28. The negative resistance in a tunnel 28. The negative resistance in a tunnel diodediode

a. is maximum at the peak point of the a. is maximum at the peak point of the characteristiccharacteristic

b. is available between the peak and b. is available between the peak and valley pointsvalley points

c. is maximum at the valley pointc. is maximum at the valley point

d. may be improved by the use of reverse d. may be improved by the use of reverse biasbias

28. The negative resistance in a tunnel 28. The negative resistance in a tunnel diodediode

a. is maximum at the peak point of the a. is maximum at the peak point of the characteristiccharacteristic

b. is available between the peak and b. is available between the peak and valley pointsvalley points

c. is maximum at the valley pointc. is maximum at the valley point

d. may be improved by the use of reverse d. may be improved by the use of reverse biasbias

29. The biggest advantage of 29. The biggest advantage of gallium antimonide over gallium antimonide over germanium for tunnel diode use is germanium for tunnel diode use is that the former has athat the former has a

a. lower noisea. lower noise

b. higher ion mobilityb. higher ion mobility

c. larger voltage swingc. larger voltage swing

d. simpler fabrication processd. simpler fabrication process

29. The biggest advantage of 29. The biggest advantage of gallium antimonide over gallium antimonide over germanium for tunnel diode use is germanium for tunnel diode use is that the former has athat the former has a

a. lower noisea. lower noise

b. higher ion mobilityb. higher ion mobility

c. larger voltage swingc. larger voltage swing

d. simpler fabrication processd. simpler fabrication process

30. Negative resistance is obtained with a 30. Negative resistance is obtained with a Gunn diode because ofGunn diode because of

a. electron transfer to less mobile energy a. electron transfer to less mobile energy levellevel

b. avalanche breakdown with the high b. avalanche breakdown with the high voltage currentvoltage current

c. tunneling across the junctionc. tunneling across the junction

d. electron domains forming at the d. electron domains forming at the junctionjunction

30. Negative resistance is obtained with a 30. Negative resistance is obtained with a Gunn diode because ofGunn diode because of

a. electron transfer to less mobile energy a. electron transfer to less mobile energy levellevel

b. avalanche breakdown with the high b. avalanche breakdown with the high voltage currentvoltage current

c. tunneling across the junctionc. tunneling across the junction

d. electron domains forming at the d. electron domains forming at the junctionjunction

31. For Gunn diodes, gallium arsenide is 31. For Gunn diodes, gallium arsenide is preferred to silicon because the formerpreferred to silicon because the former

a. has suitable empty energy band, a. has suitable empty energy band, which silicon does not havewhich silicon does not have

b. has a higher ion mobilityb. has a higher ion mobility

c. has lower noise at the highest c. has lower noise at the highest frequenciesfrequencies

d. is capable of handling higher power d. is capable of handling higher power densitiesdensities

31. For Gunn diodes, gallium arsenide is 31. For Gunn diodes, gallium arsenide is preferred to silicon because the formerpreferred to silicon because the former

a. has suitable empty energy band, a. has suitable empty energy band, which silicon does not havewhich silicon does not have

b. has a higher ion mobilityb. has a higher ion mobility

c. has lower noise at the highest c. has lower noise at the highest frequenciesfrequencies

d. is capable of handling higher power d. is capable of handling higher power densitiesdensities

32. The biggest disadvantage of 32. The biggest disadvantage of IMPATT diode is itsIMPATT diode is its

a. lower efficiency than that of the a. lower efficiency than that of the other microwave diodesother microwave diodes

b. high noiseb. high noise

c. inability to provide pulsed c. inability to provide pulsed operationoperation

d. lower ability handling abilityd. lower ability handling ability

32. The biggest disadvantage of 32. The biggest disadvantage of IMPATT diode is itsIMPATT diode is its

a. lower efficiency than that of the a. lower efficiency than that of the other microwave diodesother microwave diodes

b. high noiseb. high noise

c. inability to provide pulsed c. inability to provide pulsed operationoperation

d. lower ability handling abilityd. lower ability handling ability

33. The magnetic field is used with a 33. The magnetic field is used with a ruby maser toruby maser to

a. provide sharp focusing for the a. provide sharp focusing for the electron beamelectron beam

b. increase the population inversionb. increase the population inversion

c. allow room temperature operationc. allow room temperature operation

d. provide frequency adjustmentsd. provide frequency adjustments

33. The magnetic field is used with a 33. The magnetic field is used with a ruby maser toruby maser to

a. provide sharp focusing for the a. provide sharp focusing for the electron beamelectron beam

b. increase the population inversionb. increase the population inversion

c. allow room temperature operationc. allow room temperature operation

d. provide frequency adjustmentsd. provide frequency adjustments

34. The ruby maser has been 34. The ruby maser has been preferred to the ammonia maser preferred to the ammonia maser for microwave amplification, for microwave amplification, because the former hasbecause the former has

a. a much greater bandwidtha. a much greater bandwidth

b. a better frequency stabilityb. a better frequency stability

c. a low noise figurec. a low noise figure

d. no need for circulatord. no need for circulator

34. The ruby maser has been 34. The ruby maser has been preferred to the ammonia maser preferred to the ammonia maser for microwave amplification, for microwave amplification, because the former hasbecause the former has

a. a much greater bandwidtha. a much greater bandwidth

b. a better frequency stabilityb. a better frequency stability

c. a low noise figurec. a low noise figure

d. no need for circulatord. no need for circulator

35. Parametric amplifiers and masers 35. Parametric amplifiers and masers a re similar to each other in that a re similar to each other in that both (false)both (false)

a. must have pumpinga. must have pumpingb. are extremely low noise amplifiersb. are extremely low noise amplifiersc. must be cooled down to a few c. must be cooled down to a few

KelvinKelvind. generally require circulators, since d. generally require circulators, since

the are one port devicesthe are one port devices

35. Parametric amplifiers and masers 35. Parametric amplifiers and masers a re similar to each other in that a re similar to each other in that both (false)both (false)

a. must have pumpinga. must have pumpingb. are extremely low noise amplifiersb. are extremely low noise amplifiersc. must be cooled down to a few c. must be cooled down to a few

KelvinKelvind. generally require circulators, since d. generally require circulators, since

the are one port devicesthe are one port devices

36. Maser RF amplifier is not really 36. Maser RF amplifier is not really suitable forsuitable for

a. radio astronomya. radio astronomy

b. satellite communicationsb. satellite communications

c. radarc. radar

d. troposcatter receiversd. troposcatter receivers

36. Maser RF amplifier is not really 36. Maser RF amplifier is not really suitable forsuitable for

a. radio astronomya. radio astronomy

b. satellite communicationsb. satellite communications

c. radarc. radar

d. troposcatter receiversd. troposcatter receivers

37. The ruby maser laser differs 37. The ruby maser laser differs from the ruby maser in that the from the ruby maser in that the formerformer

a. does not require pumpinga. does not require pumping

b. needs no resonatorb. needs no resonator

c. is an oscillatorc. is an oscillator

d. produces much lower powersd. produces much lower powers

37. The ruby maser laser differs 37. The ruby maser laser differs from the ruby maser in that the from the ruby maser in that the formerformer

a. does not require pumpinga. does not require pumping

b. needs no resonatorb. needs no resonator

c. is an oscillatorc. is an oscillator

d. produces much lower powersd. produces much lower powers

38. The output from a laser is 38. The output from a laser is monochromatic; this means that monochromatic; this means that it isit is

a. infrareda. infrared

b. polarizedb. polarized

c. narrow beamc. narrow beam

d. single frequencyd. single frequency

38. The output from a laser is 38. The output from a laser is monochromatic; this means that monochromatic; this means that it isit is

a. infrareda. infrared

b. polarizedb. polarized

c. narrow beamc. narrow beam

d. single frequencyd. single frequency

39. For a given average power, the 39. For a given average power, the peak output power of a ruby laser peak output power of a ruby laser may be increased bymay be increased by

a. using coolinga. using cooling

b. using Q spoilingb. using Q spoiling

c. increasing the magnetic fieldc. increasing the magnetic field

d. dispensing the Farby-Perot d. dispensing the Farby-Perot resonatorresonator

39. For a given average power, the 39. For a given average power, the peak output power of a ruby laser peak output power of a ruby laser may be increased bymay be increased by

a. using coolinga. using cooling

b. using Q spoilingb. using Q spoiling

c. increasing the magnetic fieldc. increasing the magnetic field

d. dispensing the Farby-Perot d. dispensing the Farby-Perot resonatorresonator

40. Communications laser are used with 40. Communications laser are used with optical fiber, rather that in open links, optical fiber, rather that in open links, toto

a. ensure that the beams does not a. ensure that the beams does not spreadspread

b. prevent atmospheric interferenceb. prevent atmospheric interference

c. prevent interference by other lasersc. prevent interference by other lasers

d. ensure that people are not blinded by d. ensure that people are not blinded by themthem

40. Communications laser are used with 40. Communications laser are used with optical fiber, rather that in open links, optical fiber, rather that in open links, toto

a. ensure that the beams does not a. ensure that the beams does not spreadspread

b. prevent atmospheric interferenceb. prevent atmospheric interference

c. prevent interference by other lasersc. prevent interference by other lasers

d. ensure that people are not blinded by d. ensure that people are not blinded by themthem

41. Indicate the false statement. The 41. Indicate the false statement. The advantage of semiconductor lasers advantage of semiconductor lasers over LEDs includeover LEDs include

a. monochromatic outputa. monochromatic output

b. higher power outputb. higher power output

c. lower costc. lower cost

d. ability to be pulsed at higher ratesd. ability to be pulsed at higher rates

41. Indicate the false statement. The 41. Indicate the false statement. The advantage of semiconductor lasers advantage of semiconductor lasers over LEDs includeover LEDs include

a. monochromatic outputa. monochromatic output

b. higher power outputb. higher power output

c. lower costc. lower cost

d. ability to be pulsed at higher ratesd. ability to be pulsed at higher rates

CHAPTER 13: PULSE CHAPTER 13: PULSE COMMUNICATIONSCOMMUNICATIONS

1. Indicate which of the following is 1. Indicate which of the following is not a binary codenot a binary code

a. morsea. morse

b. baudotb. baudot

c. CCITT-2c. CCITT-2

d. ARQd. ARQ

1. Indicate which of the following is 1. Indicate which of the following is not a binary codenot a binary code

a. morsea. morse

b. baudotb. baudot

c. CCITT-2c. CCITT-2

d. ARQd. ARQ

2. To permit the selection of 1 out 2. To permit the selection of 1 out of 16 equiprobable events, the of 16 equiprobable events, the number of bits required isnumber of bits required is

a. 2a. 2

b. Logb. Log10101616

c. 8c. 8

d. 4d. 4

2. To permit the selection of 1 out 2. To permit the selection of 1 out of 16 equiprobable events, the of 16 equiprobable events, the number of bits required isnumber of bits required is

a. 2a. 2

b. Logb. Log10101616

c. 8c. 8

d. 4d. 4

3. A signaling system in which each letter 3. A signaling system in which each letter alphabet is represented by a different alphabet is represented by a different symbol is not becausesymbol is not because

a. it would be too difficult for an operator a. it would be too difficult for an operator to memorizeto memorize

b. it is redundantb. it is redundant

c. noise would introduce too many errorsc. noise would introduce too many errors

d. too many pulses per letter are requiredd. too many pulses per letter are required

3. A signaling system in which each letter 3. A signaling system in which each letter alphabet is represented by a different alphabet is represented by a different symbol is not becausesymbol is not because

a. it would be too difficult for an operator a. it would be too difficult for an operator to memorizeto memorize

b. it is redundantb. it is redundant

c. noise would introduce too many errorsc. noise would introduce too many errors

d. too many pulses per letter are requiredd. too many pulses per letter are required

4. The Hartley law states that4. The Hartley law states thata. the maximum rate of information a. the maximum rate of information

transmission depends on the transmission depends on the channel bandwidthchannel bandwidth

b. the maximum rate of information b. the maximum rate of information transmission depends on depth of transmission depends on depth of modulationmodulation

c. redundancy is essentialc. redundancy is essentiald. only binary codes may be usedd. only binary codes may be used

4. The Hartley law states that4. The Hartley law states thata. the maximum rate of information a. the maximum rate of information

transmission depends on the transmission depends on the channel bandwidthchannel bandwidth

b. the maximum rate of information b. the maximum rate of information transmission depends on depth of transmission depends on depth of modulationmodulation

c. redundancy is essentialc. redundancy is essentiald. only binary codes may be usedd. only binary codes may be used

5. Indicate the false statement. In 5. Indicate the false statement. In order to combat noise,order to combat noise,

a. the channel bandwidth may be a. the channel bandwidth may be increasedincreased

b. redundancy may be usedb. redundancy may be usedc. the transmitted power may be c. the transmitted power may be

increasedincreasedd. the signalling rate may be d. the signalling rate may be

reducedreduced

5. Indicate the false statement. In 5. Indicate the false statement. In order to combat noise,order to combat noise,

a. the channel bandwidth may be a. the channel bandwidth may be increasedincreased

b. redundancy may be usedb. redundancy may be usedc. the transmitted power may be c. the transmitted power may be

increasedincreasedd. the signalling rate may be d. the signalling rate may be

reducedreduced

6. The most common modulation 6. The most common modulation system used for telegraphy issystem used for telegraphy is

a. frequency shift keyinga. frequency shift keying

b. two tone modulationb. two tone modulation

c. pulse code modulationc. pulse code modulation

d. single tone modulationd. single tone modulation

6. The most common modulation 6. The most common modulation system used for telegraphy issystem used for telegraphy is

a. frequency shift keyinga. frequency shift keying

b. two tone modulationb. two tone modulation

c. pulse code modulationc. pulse code modulation

d. single tone modulationd. single tone modulation

7. Pulse width modulation may be 7. Pulse width modulation may be generatedgenerated

a. by differentiating pulse position a. by differentiating pulse position modulationmodulation

b. with a mono stable multivibratorb. with a mono stable multivibrator

c. by integrating the signalc. by integrating the signal

d. with free running multi vibratord. with free running multi vibrator

7. Pulse width modulation may be 7. Pulse width modulation may be generatedgenerated

a. by differentiating pulse position a. by differentiating pulse position modulationmodulation

b. with a mono stable multivibratorb. with a mono stable multivibrator

c. by integrating the signalc. by integrating the signal

d. with free running multi vibratord. with free running multi vibrator

8. Indicate which of the following 8. Indicate which of the following system is digitalsystem is digital

a. Pulse position modulationa. Pulse position modulation

b. Pulse code modulationb. Pulse code modulation

c. Pulse width modulationc. Pulse width modulation

d. Pulse frequency modulationd. Pulse frequency modulation

8. Indicate which of the following 8. Indicate which of the following system is digitalsystem is digital

a. Pulse position modulationa. Pulse position modulation

b. Pulse code modulationb. Pulse code modulation

c. Pulse width modulationc. Pulse width modulation

d. Pulse frequency modulationd. Pulse frequency modulation

9. Quantizing noise occurs in9. Quantizing noise occurs in

a. time division multiplexa. time division multiplex

b. frequency division multiplexb. frequency division multiplex

c. pulse code modulationc. pulse code modulation

d. pulse width modulationd. pulse width modulation

9. Quantizing noise occurs in9. Quantizing noise occurs in

a. time division multiplexa. time division multiplex

b. frequency division multiplexb. frequency division multiplex

c. pulse code modulationc. pulse code modulation

d. pulse width modulationd. pulse width modulation

10. The modulation system 10. The modulation system inherently most noise resistant isinherently most noise resistant is

a. SSB, suppressed carriera. SSB, suppressed carrier

b. Frequency modulationb. Frequency modulation

c. Pulse position modulationc. Pulse position modulation

d. Pulse code modulationd. Pulse code modulation

10. The modulation system 10. The modulation system inherently most noise resistant isinherently most noise resistant is

a. SSB, suppressed carriera. SSB, suppressed carrier

b. Frequency modulationb. Frequency modulation

c. Pulse position modulationc. Pulse position modulation

d. Pulse code modulationd. Pulse code modulation

11. In order to reduce quantizing noise, 11. In order to reduce quantizing noise, one mustone must

a. increase the number of standard a. increase the number of standard amplitudesamplitudes

b. sends pulses whose sides are most b. sends pulses whose sides are most nearly verticalnearly vertical

c. use an RF amplifier in the receiverc. use an RF amplifier in the receiver

d. increase the number of samples per d. increase the number of samples per secondsecond

11. In order to reduce quantizing noise, 11. In order to reduce quantizing noise, one mustone must

a. increase the number of standard a. increase the number of standard amplitudesamplitudes

b. sends pulses whose sides are most b. sends pulses whose sides are most nearly verticalnearly vertical

c. use an RF amplifier in the receiverc. use an RF amplifier in the receiver

d. increase the number of samples per d. increase the number of samples per secondsecond

12. The Hartley Shannon theorems sets 12. The Hartley Shannon theorems sets a limit on thea limit on the

a. highest frequency that may be sent a. highest frequency that may be sent over a given channelover a given channel

b. maximum capacity of a channel with b. maximum capacity of a channel with a given noise levela given noise level

c. maximum number of coding levels in c. maximum number of coding levels in a channel with a given noise levela channel with a given noise level

d. maximum number of quantizing d. maximum number of quantizing levels in a channel of a given levels in a channel of a given bandwidthbandwidth

12. The Hartley Shannon theorems sets 12. The Hartley Shannon theorems sets a limit on thea limit on the

a. highest frequency that may be sent a. highest frequency that may be sent over a given channelover a given channel

b. maximum capacity of a channel with b. maximum capacity of a channel with a given noise levela given noise level

c. maximum number of coding levels in c. maximum number of coding levels in a channel with a given noise levela channel with a given noise level

d. maximum number of quantizing d. maximum number of quantizing levels in a channel of a given levels in a channel of a given bandwidthbandwidth

13. Indicate which of the following 13. Indicate which of the following pulse modulation system analog.pulse modulation system analog.

a. PCMa. PCM

b. Differential PCMb. Differential PCM

c. PWMc. PWM

d. Deltad. Delta

13. Indicate which of the following 13. Indicate which of the following pulse modulation system analog.pulse modulation system analog.

a. PCMa. PCM

b. Differential PCMb. Differential PCM

c. PWMc. PWM

d. Deltad. Delta

14. Companding is used14. Companding is useda. to overcome quantizing noise in a. to overcome quantizing noise in

PCMPCMb. in PCM transmitter, to allow b. in PCM transmitter, to allow

amplitude limiting in the receiversamplitude limiting in the receiversc. to protect small signals in PCM c. to protect small signals in PCM

from quantizing distortionfrom quantizing distortiond. in the PCM receivers to overcome d. in the PCM receivers to overcome

impulse noiseimpulse noise

14. Companding is used14. Companding is useda. to overcome quantizing noise in a. to overcome quantizing noise in

PCMPCMb. in PCM transmitter, to allow b. in PCM transmitter, to allow

amplitude limiting in the receiversamplitude limiting in the receiversc. to protect small signals in PCM c. to protect small signals in PCM

from quantizing distortionfrom quantizing distortiond. in the PCM receivers to overcome d. in the PCM receivers to overcome

impulse noiseimpulse noise

15. The biggest disadvantage of PCM is15. The biggest disadvantage of PCM is

a. its inability to handle analog signalsa. its inability to handle analog signals

b. the high error rate which its b. the high error rate which its quantizing noise introducesquantizing noise introduces

c. its incompatibility with TDMc. its incompatibility with TDM

d. the large bandwidths that are d. the large bandwidths that are required for itrequired for it

15. The biggest disadvantage of PCM is15. The biggest disadvantage of PCM is

a. its inability to handle analog signalsa. its inability to handle analog signals

b. the high error rate which its b. the high error rate which its quantizing noise introducesquantizing noise introduces

c. its incompatibility with TDMc. its incompatibility with TDM

d. the large bandwidths that are d. the large bandwidths that are required for itrequired for it

CHAPTER 14: DIGITAL CHAPTER 14: DIGITAL COMMUNICATIONSCOMMUNICATIONS

1. Digital signals1. Digital signals

a. do not provide a continuous set a. do not provide a continuous set of valuesof values

b. present values as discrete stepsb. present values as discrete steps

c. can utilized decimal or binary c. can utilized decimal or binary systemssystems

d. all of the aboved. all of the above

1. Digital signals1. Digital signals

a. do not provide a continuous set a. do not provide a continuous set of valuesof values

b. present values as discrete stepsb. present values as discrete steps

c. can utilized decimal or binary c. can utilized decimal or binary systemssystems

d. all of the aboved. all of the above

2. The event which marked the start 2. The event which marked the start of the modern computer age wasof the modern computer age was

a. design of the ENIAC computera. design of the ENIAC computer

b. development of the Hollerith codeb. development of the Hollerith code

c. development of the transistorc. development of the transistor

d. development of the disk drives d. development of the disk drives for data storagefor data storage

2. The event which marked the start 2. The event which marked the start of the modern computer age wasof the modern computer age was

a. design of the ENIAC computera. design of the ENIAC computer

b. development of the Hollerith codeb. development of the Hollerith code

c. development of the transistorc. development of the transistor

d. development of the disk drives d. development of the disk drives for data storagefor data storage

3. The baud rate3. The baud rate

a. is always equal to the bit transfer a. is always equal to the bit transfer raterate

b. is equal to twice the bandwidth of b. is equal to twice the bandwidth of an ideal channelan ideal channel

c. is not equal to the signaling ratec. is not equal to the signaling rate

d. is equal to one half the bandwidth d. is equal to one half the bandwidth of an ideal channelof an ideal channel

3. The baud rate3. The baud rate

a. is always equal to the bit transfer a. is always equal to the bit transfer raterate

b. is equal to twice the bandwidth of b. is equal to twice the bandwidth of an ideal channelan ideal channel

c. is not equal to the signaling ratec. is not equal to the signaling rate

d. is equal to one half the bandwidth d. is equal to one half the bandwidth of an ideal channelof an ideal channel

4. The Shannon Hartley Law4. The Shannon Hartley Law

a. refers to distortiona. refers to distortion

b. defines bandwidthb. defines bandwidth

c. describes signalling ratesc. describes signalling rates

d. refers to noised. refers to noise

4. The Shannon Hartley Law4. The Shannon Hartley Law

a. refers to distortiona. refers to distortion

b. defines bandwidthb. defines bandwidth

c. describes signalling ratesc. describes signalling rates

d. refers to noised. refers to noise

5. The code which provides parity 5. The code which provides parity check ischeck is

a. Baudota. Baudot

b. ASCIIb. ASCII

c. EBCDICc. EBCDIC

d. CCITT-2d. CCITT-2

5. The code which provides parity 5. The code which provides parity check ischeck is

a. Baudota. Baudot

b. ASCIIb. ASCII

c. EBCDICc. EBCDIC

d. CCITT-2d. CCITT-2

6. Forward error correcting code corrects 6. Forward error correcting code corrects errors byerrors by

a. requiring partial retransmission of the a. requiring partial retransmission of the signalsignal

b. requiring retransmission of the entire b. requiring retransmission of the entire signalsignal

c. requiring no part pf the signal to be c. requiring no part pf the signal to be retransmittedretransmitted

d. using parity to correct the errors in all d. using parity to correct the errors in all casescases

6. Forward error correcting code corrects 6. Forward error correcting code corrects errors byerrors by

a. requiring partial retransmission of the a. requiring partial retransmission of the signalsignal

b. requiring retransmission of the entire b. requiring retransmission of the entire signalsignal

c. requiring no part pf the signal to be c. requiring no part pf the signal to be retransmittedretransmitted

d. using parity to correct the errors in all d. using parity to correct the errors in all casescases

7. Full duplex operation7. Full duplex operation

a. requires two pairs of cablesa. requires two pairs of cables

b. can transfer data in both b. can transfer data in both directions at oncedirections at once

c. requires modems at both ends of c. requires modems at both ends of the circuitthe circuit

d. all of the aboved. all of the above

7. Full duplex operation7. Full duplex operation

a. requires two pairs of cablesa. requires two pairs of cables

b. can transfer data in both b. can transfer data in both directions at oncedirections at once

c. requires modems at both ends of c. requires modems at both ends of the circuitthe circuit

d. all of the aboved. all of the above

8. The RS-232 interface8. The RS-232 interface

a. interconnects data sets and a. interconnects data sets and transmission circuitstransmission circuits

b. uses several different connectorsb. uses several different connectors

c. permits custom wiring of signal c. permits custom wiring of signal lines to the connector pins as lines to the connector pins as desireddesired

d. all of the aboved. all of the above

8. The RS-232 interface8. The RS-232 interface

a. interconnects data sets and a. interconnects data sets and transmission circuitstransmission circuits

b. uses several different connectorsb. uses several different connectors

c. permits custom wiring of signal c. permits custom wiring of signal lines to the connector pins as lines to the connector pins as desireddesired

d. all of the aboved. all of the above

9. Switching systems9. Switching systems

a. improve the efficiency of the a. improve the efficiency of the data transferdata transfer

b. are not used in data systemb. are not used in data system

c. require additional linesc. require additional lines

d. are limited to small data d. are limited to small data networksnetworks

9. Switching systems9. Switching systems

a. improve the efficiency of the a. improve the efficiency of the data transferdata transfer

b. are not used in data systemb. are not used in data system

c. require additional linesc. require additional lines

d. are limited to small data d. are limited to small data networksnetworks

10. The data transmission rate of a 10. The data transmission rate of a modem is measured inmodem is measured in

a. Bytes per seconda. Bytes per second

b. Baud rateb. Baud rate

c. Bits per secondc. Bits per second

d. Megahertzd. Megahertz

10. The data transmission rate of a 10. The data transmission rate of a modem is measured inmodem is measured in

a. Bytes per seconda. Bytes per second

b. Baud rateb. Baud rate

c. Bits per secondc. Bits per second

d. Megahertzd. Megahertz

CHAPTER 15: CHAPTER 15: BROADBAND BROADBAND COMMUNICATIONS COMMUNICATIONS SYSTEMSYSTEM

1. Broadband long distance 1. Broadband long distance communications are originally communications are originally made possible by the advent ofmade possible by the advent of

a. telegraph cablesa. telegraph cables

b. repeater amplifiersb. repeater amplifiers

c. HF radioc. HF radio

d. Geostationary satellitesd. Geostationary satellites

1. Broadband long distance 1. Broadband long distance communications are originally communications are originally made possible by the advent ofmade possible by the advent of

a. telegraph cablesa. telegraph cables

b. repeater amplifiersb. repeater amplifiers

c. HF radioc. HF radio

d. Geostationary satellitesd. Geostationary satellites

2. Scheme in which several 2. Scheme in which several channels are interleaved and then channels are interleaved and then transmitted together is known astransmitted together is known as

a. Frequency division multiplexa. Frequency division multiplex

b. Time division multiplexb. Time division multiplex

c. A groupc. A group

d. A super groupd. A super group

2. Scheme in which several 2. Scheme in which several channels are interleaved and then channels are interleaved and then transmitted together is known astransmitted together is known as

a. Frequency division multiplexa. Frequency division multiplex

b. Time division multiplexb. Time division multiplex

c. A groupc. A group

d. A super groupd. A super group

3. Basic group B3. Basic group B

a. occupies the frequency range a. occupies the frequency range from 60 to 108 KHzfrom 60 to 108 KHz

b. consist of erect channels onlyb. consist of erect channels only

c. is formed at the group c. is formed at the group translating equipmenttranslating equipment

d. consist of five super groupd. consist of five super group

3. Basic group B3. Basic group B

a. occupies the frequency range a. occupies the frequency range from 60 to 108 KHzfrom 60 to 108 KHz

b. consist of erect channels onlyb. consist of erect channels only

c. is formed at the group c. is formed at the group translating equipmenttranslating equipment

d. consist of five super groupd. consist of five super group

4. Time division multiplex4. Time division multiplexa. can be used with PCM onlya. can be used with PCM onlyb. combines five groups into a b. combines five groups into a

super groupsuper groupc. stacks 24 channels in adjacent c. stacks 24 channels in adjacent

frequency slotsfrequency slotsd. interleaves pulses belonging to d. interleaves pulses belonging to

different transmissionsdifferent transmissions

4. Time division multiplex4. Time division multiplexa. can be used with PCM onlya. can be used with PCM onlyb. combines five groups into a b. combines five groups into a

super groupsuper groupc. stacks 24 channels in adjacent c. stacks 24 channels in adjacent

frequency slotsfrequency slotsd. interleaves pulses belonging to d. interleaves pulses belonging to

different transmissionsdifferent transmissions

5. The number of repeaters along a 5. The number of repeaters along a coaxial cable link depends oncoaxial cable link depends on

a. whether separate tubes are used a. whether separate tubes are used for the two directions of for the two directions of transmissiontransmission

b. the bandwidth of the systemb. the bandwidth of the systemc. the number of coaxial cables in c. the number of coaxial cables in

the tubethe tubed. the separation of the equalizersd. the separation of the equalizers

5. The number of repeaters along a 5. The number of repeaters along a coaxial cable link depends oncoaxial cable link depends on

a. whether separate tubes are used a. whether separate tubes are used for the two directions of for the two directions of transmissiontransmission

b. the bandwidth of the systemb. the bandwidth of the systemc. the number of coaxial cables in c. the number of coaxial cables in

the tubethe tubed. the separation of the equalizersd. the separation of the equalizers

6. Super group pilot is6. Super group pilot is

a. applied at each multiplexing baya. applied at each multiplexing bay

b. used to regulate the gain of b. used to regulate the gain of individual repeatersindividual repeaters

c. applied at each adjustable c. applied at each adjustable equalizerequalizer

d. fed in at a GTEd. fed in at a GTE

6. Super group pilot is6. Super group pilot is

a. applied at each multiplexing baya. applied at each multiplexing bay

b. used to regulate the gain of b. used to regulate the gain of individual repeatersindividual repeaters

c. applied at each adjustable c. applied at each adjustable equalizerequalizer

d. fed in at a GTEd. fed in at a GTE

7. Microwave link repeaters are 7. Microwave link repeaters are typically 50km aparttypically 50km apart

a. because of atmospheric attenuationa. because of atmospheric attenuation

b. because of output power limitationsb. because of output power limitations

c. because of earths curvaturec. because of earths curvature

d. to ensure that the applied dc d. to ensure that the applied dc voltage is not excessivevoltage is not excessive

7. Microwave link repeaters are 7. Microwave link repeaters are typically 50km aparttypically 50km apart

a. because of atmospheric attenuationa. because of atmospheric attenuation

b. because of output power limitationsb. because of output power limitations

c. because of earths curvaturec. because of earths curvature

d. to ensure that the applied dc d. to ensure that the applied dc voltage is not excessivevoltage is not excessive

8. Microwave links are generally 8. Microwave links are generally preferred to coaxial cable for preferred to coaxial cable for television transmission becausetelevision transmission because

a. the have less overall phase a. the have less overall phase distortiondistortion

b. they are cheaperb. they are cheaperc. of their greater bandwidthsc. of their greater bandwidthsd. of their relatively immunity to d. of their relatively immunity to

impulse noiseimpulse noise

8. Microwave links are generally 8. Microwave links are generally preferred to coaxial cable for preferred to coaxial cable for television transmission becausetelevision transmission because

a. the have less overall phase a. the have less overall phase distortiondistortion

b. they are cheaperb. they are cheaperc. of their greater bandwidthsc. of their greater bandwidthsd. of their relatively immunity to d. of their relatively immunity to

impulse noiseimpulse noise

9. Armored submarine cable is used9. Armored submarine cable is useda. to protect the cable at great a. to protect the cable at great

depthsdepthsb. to prevent inadvertent ploughing b. to prevent inadvertent ploughing

in of the cablein of the cablec. for the shallow shore ends of the c. for the shallow shore ends of the

cablecabled. to prevent insulation breakdown d. to prevent insulation breakdown

from the high feeds voltagesfrom the high feeds voltages

9. Armored submarine cable is used9. Armored submarine cable is useda. to protect the cable at great a. to protect the cable at great

depthsdepthsb. to prevent inadvertent ploughing b. to prevent inadvertent ploughing

in of the cablein of the cablec. for the shallow shore ends of the c. for the shallow shore ends of the

cablecabled. to prevent insulation breakdown d. to prevent insulation breakdown

from the high feeds voltagesfrom the high feeds voltages

10. Submarine cable repeater contains 10. Submarine cable repeater contains among other equipmentsamong other equipments

a. a dc power supply and regulatora. a dc power supply and regulator

b. filters for two directions of b. filters for two directions of transmissiontransmission

c. multiplexing and demultiplexing c. multiplexing and demultiplexing equipmentequipment

d. pilot inject and pilot extract d. pilot inject and pilot extract equipmentequipment

10. Submarine cable repeater contains 10. Submarine cable repeater contains among other equipmentsamong other equipments

a. a dc power supply and regulatora. a dc power supply and regulator

b. filters for two directions of b. filters for two directions of transmissiontransmission

c. multiplexing and demultiplexing c. multiplexing and demultiplexing equipmentequipment

d. pilot inject and pilot extract d. pilot inject and pilot extract equipmentequipment

11. Geostationary satellite11. Geostationary satellite

a. is motionless in space (except for its a. is motionless in space (except for its spins)spins)

b. is not really stationary at all but its b. is not really stationary at all but its orbits the earth within a 24hr periodorbits the earth within a 24hr period

c. appears stationary above the Earth’s c. appears stationary above the Earth’s magnetic polesmagnetic poles

d. is located at height of 35,800km to d. is located at height of 35,800km to ensure global coverageensure global coverage

11. Geostationary satellite11. Geostationary satellite

a. is motionless in space (except for its a. is motionless in space (except for its spins)spins)

b. is not really stationary at all but its b. is not really stationary at all but its orbits the earth within a 24hr periodorbits the earth within a 24hr period

c. appears stationary above the Earth’s c. appears stationary above the Earth’s magnetic polesmagnetic poles

d. is located at height of 35,800km to d. is located at height of 35,800km to ensure global coverageensure global coverage

12. Indicate the correct statement regarding 12. Indicate the correct statement regarding satellite communications.satellite communications.

a. if two earth stations do not face a common a. if two earth stations do not face a common satellite the should be communicate via double satellite the should be communicate via double satellite hopsatellite hop

b. satellite are allocated so that it is impossible for b. satellite are allocated so that it is impossible for to earths station not to face the same satelliteto earths station not to face the same satellite

c. collocated earth station are used for frequency c. collocated earth station are used for frequency diversitydiversity

d. a satellite earth station must have as many d. a satellite earth station must have as many receiver chains as there are carriers transmitted receiver chains as there are carriers transmitted to it.to it.

12. Indicate the correct statement regarding 12. Indicate the correct statement regarding satellite communications.satellite communications.

a. if two earth stations do not face a common a. if two earth stations do not face a common satellite the should be communicate via double satellite the should be communicate via double satellite hopsatellite hop

b. satellite are allocated so that it is impossible for b. satellite are allocated so that it is impossible for to earths station not to face the same satelliteto earths station not to face the same satellite

c. collocated earth station are used for frequency c. collocated earth station are used for frequency diversitydiversity

d. a satellite earth station must have as many d. a satellite earth station must have as many receiver chains as there are carriers transmitted receiver chains as there are carriers transmitted to it.to it.

13. Satellite used for inter 13. Satellite used for inter continental communications are continental communications are known asknown as

a. Comsata. Comsat

b. Domsatb. Domsat

c. Marisatc. Marisat

d. Intelsatd. Intelsat

13. Satellite used for inter 13. Satellite used for inter continental communications are continental communications are known asknown as

a. Comsata. Comsat

b. Domsatb. Domsat

c. Marisatc. Marisat

d. Intelsatd. Intelsat

14. Identical telephone number in 14. Identical telephone number in different parts of a country are different parts of a country are distinguished by theirdistinguished by their

a. language digitsa. language digits

b. access digitsb. access digits

c. area codesc. area codes

d. central office codesd. central office codes

14. Identical telephone number in 14. Identical telephone number in different parts of a country are different parts of a country are distinguished by theirdistinguished by their

a. language digitsa. language digits

b. access digitsb. access digits

c. area codesc. area codes

d. central office codesd. central office codes

15. Telephone traffic is measured15. Telephone traffic is measured

a. with echo cancellersa. with echo cancellers

b. by their relative congestionsb. by their relative congestions

c. in terms of the grade of servicesc. in terms of the grade of services

d. in erlangsd. in erlangs

15. Telephone traffic is measured15. Telephone traffic is measured

a. with echo cancellersa. with echo cancellers

b. by their relative congestionsb. by their relative congestions

c. in terms of the grade of servicesc. in terms of the grade of services

d. in erlangsd. in erlangs

16. In order to separate channels in 16. In order to separate channels in a TDM receiver, it is necessary to a TDM receiver, it is necessary to useuse

a. AND gatesa. AND gates

b. Bandpass filterb. Bandpass filter

c. Differentiationc. Differentiation

d. Integrationd. Integration

16. In order to separate channels in 16. In order to separate channels in a TDM receiver, it is necessary to a TDM receiver, it is necessary to useuse

a. AND gatesa. AND gates

b. Bandpass filterb. Bandpass filter

c. Differentiationc. Differentiation

d. Integrationd. Integration

17. To separate channels in a FDM 17. To separate channels in a FDM receiver, it is necessary to usereceiver, it is necessary to use

a. AND gatesa. AND gates

b. Bandpass filterb. Bandpass filter

c. Differentiationc. Differentiation

d. Integrationd. Integration

17. To separate channels in a FDM 17. To separate channels in a FDM receiver, it is necessary to usereceiver, it is necessary to use

a. AND gatesa. AND gates

b. Bandpass filterb. Bandpass filter

c. Differentiationc. Differentiation

d. Integrationd. Integration

18. Higher order TDM levels are 18. Higher order TDM levels are obtained byobtained by

a. dividing pulse widthsa. dividing pulse widths

b. using the a-lawb. using the a-law

c. using the u-lawc. using the u-law

d. forming supermastergroupsd. forming supermastergroups

18. Higher order TDM levels are 18. Higher order TDM levels are obtained byobtained by

a. dividing pulse widthsa. dividing pulse widths

b. using the a-lawb. using the a-law

c. using the u-lawc. using the u-law

d. forming supermastergroupsd. forming supermastergroups

19. Losses in optical fiber can be 19. Losses in optical fiber can be caused by (false)caused by (false)

a. impuritiesa. impurities

b. microbendingb. microbending

c. attenuation in the glassc. attenuation in the glass

d. stepped index operationd. stepped index operation

19. Losses in optical fiber can be 19. Losses in optical fiber can be caused by (false)caused by (false)

a. impuritiesa. impurities

b. microbendingb. microbending

c. attenuation in the glassc. attenuation in the glass

d. stepped index operationd. stepped index operation

20. The 1.55um “window” is not yet in used 20. The 1.55um “window” is not yet in used with fiber optic system becausewith fiber optic system because

a. the attenuation is higher than at 0.85uma. the attenuation is higher than at 0.85um

b. the attenuation is higher than at 1.3umb. the attenuation is higher than at 1.3um

c. suitable laser devices have not yet been c. suitable laser devices have not yet been developeddeveloped

d. it does not lend itself to wavelength d. it does not lend itself to wavelength multiplexingmultiplexing

20. The 1.55um “window” is not yet in used 20. The 1.55um “window” is not yet in used with fiber optic system becausewith fiber optic system because

a. the attenuation is higher than at 0.85uma. the attenuation is higher than at 0.85um

b. the attenuation is higher than at 1.3umb. the attenuation is higher than at 1.3um

c. suitable laser devices have not yet been c. suitable laser devices have not yet been developeddeveloped

d. it does not lend itself to wavelength d. it does not lend itself to wavelength multiplexingmultiplexing

21. Indicate which of the following 21. Indicate which of the following is not a submarine cableis not a submarine cable

a. TAT-7a. TAT-7

b. INTELSAT Vb. INTELSAT V

c. ATLANTISc. ATLANTIS

d. CANTAT 2d. CANTAT 2

21. Indicate which of the following 21. Indicate which of the following is not a submarine cableis not a submarine cable

a. TAT-7a. TAT-7

b. INTELSAT Vb. INTELSAT V

c. ATLANTISc. ATLANTIS

d. CANTAT 2d. CANTAT 2

22. Indicate which of the following 22. Indicate which of the following is an American Domsat systemis an American Domsat system

a. INTELSATa. INTELSAT

b. COMSATb. COMSAT

c. TELSATc. TELSAT

d. INMARSATd. INMARSAT

22. Indicate which of the following 22. Indicate which of the following is an American Domsat systemis an American Domsat system

a. INTELSATa. INTELSAT

b. COMSATb. COMSAT

c. TELSATc. TELSAT

d. INMARSATd. INMARSAT

CHAPTER 16: RADAR CHAPTER 16: RADAR SYSTEMSYSTEM

1. If the peak transmitted power in 1. If the peak transmitted power in a radar system is increased by a radar system is increased by factor of 16, the maximum range factor of 16, the maximum range will be increased by factor ofwill be increased by factor of

a. 2a. 2b. 4b. 4c. 8c. 8d. 16d. 16

1. If the peak transmitted power in 1. If the peak transmitted power in a radar system is increased by a radar system is increased by factor of 16, the maximum range factor of 16, the maximum range will be increased by factor ofwill be increased by factor of

a. 2a. 2b. 4b. 4c. 8c. 8d. 16d. 16

2. If the antenna diameter in a 2. If the antenna diameter in a radar system is increased by radar system is increased by factor of 4, the maximum range factor of 4, the maximum range will be increased by factor ofwill be increased by factor of

a. (2)^1/2a. (2)^1/2b. 2b. 2c. 4c. 4d. 8d. 8

2. If the antenna diameter in a 2. If the antenna diameter in a radar system is increased by radar system is increased by factor of 4, the maximum range factor of 4, the maximum range will be increased by factor ofwill be increased by factor of

a. (2)^1/2a. (2)^1/2b. 2b. 2c. 4c. 4d. 8d. 8

3. If the ratio of the antenna 3. If the ratio of the antenna diameter to the wavelength in a diameter to the wavelength in a radar system is high this will result radar system is high this will result in (false)in (false)

a. large maximum rangea. large maximum range

b. good target discriminationb. good target discrimination

c. difficult target acquisitionc. difficult target acquisition

d. increased capture aread. increased capture area

3. If the ratio of the antenna 3. If the ratio of the antenna diameter to the wavelength in a diameter to the wavelength in a radar system is high this will result radar system is high this will result in (false)in (false)

a. large maximum rangea. large maximum range

b. good target discriminationb. good target discrimination

c. difficult target acquisitionc. difficult target acquisition

d. increased capture aread. increased capture area

4. The radar cross section to a target 4. The radar cross section to a target (false)(false)

a. depends on the frequency useda. depends on the frequency used

b. may be reduced by special coating of b. may be reduced by special coating of the targetthe target

c. depends on the aspect of a target, if c. depends on the aspect of a target, if this is nonsphericalthis is nonspherical

d. is equal to the actual cross sectional d. is equal to the actual cross sectional area for small targetsarea for small targets

4. The radar cross section to a target 4. The radar cross section to a target (false)(false)

a. depends on the frequency useda. depends on the frequency used

b. may be reduced by special coating of b. may be reduced by special coating of the targetthe target

c. depends on the aspect of a target, if c. depends on the aspect of a target, if this is nonsphericalthis is nonspherical

d. is equal to the actual cross sectional d. is equal to the actual cross sectional area for small targetsarea for small targets

5. Flat topped rectangular pulses must 5. Flat topped rectangular pulses must be transmitted in radar to (false)be transmitted in radar to (false)

a. allow good minimum rangea. allow good minimum rangeb. make the returned echoes easier to b. make the returned echoes easier to

distinguish from noisedistinguish from noisec. prevent frequency changes in the c. prevent frequency changes in the

magnetronmagnetrond. allow accurate range measurementsd. allow accurate range measurements

5. Flat topped rectangular pulses must 5. Flat topped rectangular pulses must be transmitted in radar to (false)be transmitted in radar to (false)

a. allow good minimum rangea. allow good minimum rangeb. make the returned echoes easier to b. make the returned echoes easier to

distinguish from noisedistinguish from noisec. prevent frequency changes in the c. prevent frequency changes in the

magnetronmagnetrond. allow accurate range measurementsd. allow accurate range measurements

6. High PRF will (false)6. High PRF will (false)a. make the returned echoes easier a. make the returned echoes easier

to distinguish from noiseto distinguish from noiseb. make target tracing easier with b. make target tracing easier with

conical scanningconical scanningc. increase maximum rangec. increase maximum ranged. have no effect on the range d. have no effect on the range

resolutionresolution

6. High PRF will (false)6. High PRF will (false)a. make the returned echoes easier a. make the returned echoes easier

to distinguish from noiseto distinguish from noiseb. make target tracing easier with b. make target tracing easier with

conical scanningconical scanningc. increase maximum rangec. increase maximum ranged. have no effect on the range d. have no effect on the range

resolutionresolution

7. The IF bandwidth of a radar 7. The IF bandwidth of a radar receiver is inversely proportional to receiver is inversely proportional to thethe

a. pulse widtha. pulse width

b. pulse repetition frequencyb. pulse repetition frequency

c. pulse intervalc. pulse interval

d. square root of the peak d. square root of the peak transmitted powertransmitted power

7. The IF bandwidth of a radar 7. The IF bandwidth of a radar receiver is inversely proportional to receiver is inversely proportional to thethe

a. pulse widtha. pulse width

b. pulse repetition frequencyb. pulse repetition frequency

c. pulse intervalc. pulse interval

d. square root of the peak d. square root of the peak transmitted powertransmitted power

8. If a return echo arrives after the 8. If a return echo arrives after the allocated pulse interval,allocated pulse interval,

a. it will interfere with the operation a. it will interfere with the operation of the transmitterof the transmitter

b. the receiver might be overloadedb. the receiver might be overloadedc. it will not be receivedc. it will not be receivedd. the target will appear closer than d. the target will appear closer than

it really isit really is

8. If a return echo arrives after the 8. If a return echo arrives after the allocated pulse interval,allocated pulse interval,

a. it will interfere with the operation a. it will interfere with the operation of the transmitterof the transmitter

b. the receiver might be overloadedb. the receiver might be overloadedc. it will not be receivedc. it will not be receivedd. the target will appear closer than d. the target will appear closer than

it really isit really is

9. After a target has been acquired, 9. After a target has been acquired, the best scanning system for the best scanning system for tracking istracking is

a. noddinga. nodding

b. spiralb. spiral

c. conicalc. conical

d. helicald. helical

9. After a target has been acquired, 9. After a target has been acquired, the best scanning system for the best scanning system for tracking istracking is

a. noddinga. nodding

b. spiralb. spiral

c. conicalc. conical

d. helicald. helical

10. If the target cross section is 10. If the target cross section is changing, the best system for changing, the best system for accurate tracking isaccurate tracking is

a. lobe switchinga. lobe switching

b. sequential lobbingb. sequential lobbing

c. conical scanningc. conical scanning

d. mono pulsed. mono pulse

10. If the target cross section is 10. If the target cross section is changing, the best system for changing, the best system for accurate tracking isaccurate tracking is

a. lobe switchinga. lobe switching

b. sequential lobbingb. sequential lobbing

c. conical scanningc. conical scanning

d. mono pulsed. mono pulse

11. The biggest disadvantage of CW 11. The biggest disadvantage of CW Doppler radar is thatDoppler radar is that

a. it does not give the target velocitya. it does not give the target velocity

b. it does not give the target rangeb. it does not give the target range

c. a transponder is required at the c. a transponder is required at the targettarget

d. it does not give the target positiond. it does not give the target position

11. The biggest disadvantage of CW 11. The biggest disadvantage of CW Doppler radar is thatDoppler radar is that

a. it does not give the target velocitya. it does not give the target velocity

b. it does not give the target rangeb. it does not give the target range

c. a transponder is required at the c. a transponder is required at the targettarget

d. it does not give the target positiond. it does not give the target position

12. A scope displays12. A scope displays

a. the target position and rangea. the target position and range

b. the target range, but not positionb. the target range, but not position

c. the target position, but not the c. the target position, but not the rangerange

d. neither range nor position, but d. neither range nor position, but only velocityonly velocity

12. A scope displays12. A scope displays

a. the target position and rangea. the target position and range

b. the target range, but not positionb. the target range, but not position

c. the target position, but not the c. the target position, but not the rangerange

d. neither range nor position, but d. neither range nor position, but only velocityonly velocity

13. The Doppler effect is used in 13. The Doppler effect is used in (false)(false)

a. moving target plotting on the PPIa. moving target plotting on the PPI

b. the MTI systemb. the MTI system

c. FM radarc. FM radar

d. CW radard. CW radar

13. The Doppler effect is used in 13. The Doppler effect is used in (false)(false)

a. moving target plotting on the PPIa. moving target plotting on the PPI

b. the MTI systemb. the MTI system

c. FM radarc. FM radar

d. CW radard. CW radar

14. The coho in MTI radar operates 14. The coho in MTI radar operates at theat the

a. intermediate frequencya. intermediate frequency

b. transmitted frequencyb. transmitted frequency

c. received frequencyc. received frequency

d. pulse repetition frequencyd. pulse repetition frequency

14. The coho in MTI radar operates 14. The coho in MTI radar operates at theat the

a. intermediate frequencya. intermediate frequency

b. transmitted frequencyb. transmitted frequency

c. received frequencyc. received frequency

d. pulse repetition frequencyd. pulse repetition frequency

15. The function of the quartz delay line 15. The function of the quartz delay line in an MTI radar is toin an MTI radar is to

a. help subtracting a complete scan from a. help subtracting a complete scan from the previous scanthe previous scan

b. match the phase of the coho and the b. match the phase of the coho and the stalostalo

c. match the phase of the coho and the c. match the phase of the coho and the output oscillatoroutput oscillator

d. delay a sweep so that the next sweep d. delay a sweep so that the next sweep can be subtracted from itcan be subtracted from it

15. The function of the quartz delay line 15. The function of the quartz delay line in an MTI radar is toin an MTI radar is to

a. help subtracting a complete scan from a. help subtracting a complete scan from the previous scanthe previous scan

b. match the phase of the coho and the b. match the phase of the coho and the stalostalo

c. match the phase of the coho and the c. match the phase of the coho and the output oscillatoroutput oscillator

d. delay a sweep so that the next sweep d. delay a sweep so that the next sweep can be subtracted from itcan be subtracted from it

16. A solution to the “blind speed” 16. A solution to the “blind speed” problem is toproblem is to

a. change the Doppler frequencya. change the Doppler frequency

b. Vary the PRFb. Vary the PRF

c. Use monopulsec. Use monopulse

d. Use MTId. Use MTI

16. A solution to the “blind speed” 16. A solution to the “blind speed” problem is toproblem is to

a. change the Doppler frequencya. change the Doppler frequency

b. Vary the PRFb. Vary the PRF

c. Use monopulsec. Use monopulse

d. Use MTId. Use MTI

17. Indicate which one of the following 17. Indicate which one of the following applications are advantages of radar applications are advantages of radar beacons is false:beacons is false:

a. target identificationa. target identification

b. navigationb. navigation

c. very significant extension of the c. very significant extension of the maximum rangemaximum range

d. more accurate tracking of enemy d. more accurate tracking of enemy targetstargets

17. Indicate which one of the following 17. Indicate which one of the following applications are advantages of radar applications are advantages of radar beacons is false:beacons is false:

a. target identificationa. target identification

b. navigationb. navigation

c. very significant extension of the c. very significant extension of the maximum rangemaximum range

d. more accurate tracking of enemy d. more accurate tracking of enemy targetstargets

18. Compared with other types of radar, 18. Compared with other types of radar, phased array radar has the following phased array radar has the following advantages (false)advantages (false)

a. very fast scanninga. very fast scanning

b. ability to tract and scan b. ability to tract and scan simultaneouslysimultaneously

c. circuit simplicityc. circuit simplicity

d. ability to track may targets d. ability to track may targets simultaneouslysimultaneously

18. Compared with other types of radar, 18. Compared with other types of radar, phased array radar has the following phased array radar has the following advantages (false)advantages (false)

a. very fast scanninga. very fast scanning

b. ability to tract and scan b. ability to tract and scan simultaneouslysimultaneously

c. circuit simplicityc. circuit simplicity

d. ability to track may targets d. ability to track may targets simultaneouslysimultaneously

CHAPTER 17: CHAPTER 17: TELEVISION TELEVISION FUNDAMENTALSFUNDAMENTALS

1. The number of lines per field in 1. The number of lines per field in the United State TV system isthe United State TV system is

a. 262 ½a. 262 ½

b. 525b. 525

c. 30c. 30

d. 60d. 60

1. The number of lines per field in 1. The number of lines per field in the United State TV system isthe United State TV system is

a. 262 ½a. 262 ½

b. 525b. 525

c. 30c. 30

d. 60d. 60

2. The number of frames per 2. The number of frames per second in the US TV system issecond in the US TV system is

a. 60a. 60

b. 262 ½b. 262 ½

c. 4.5c. 4.5

d. 30d. 30

2. The number of frames per 2. The number of frames per second in the US TV system issecond in the US TV system is

a. 60a. 60

b. 262 ½b. 262 ½

c. 4.5c. 4.5

d. 30d. 30

3. The number of lines per second 3. The number of lines per second in the US TV system isin the US TV system is

a. 31500a. 31500

b. 15750b. 15750

c. 262 ½c. 262 ½

d. 525d. 525

3. The number of lines per second 3. The number of lines per second in the US TV system isin the US TV system is

a. 31500a. 31500

b. 15750b. 15750

c. 262 ½c. 262 ½

d. 525d. 525

4. The channel width in the US TV 4. The channel width in the US TV system, in MHz issystem, in MHz is

a. 41.25a. 41.25

b. 6b. 6

c. 4.5c. 4.5

d. 3.58d. 3.58

4. The channel width in the US TV 4. The channel width in the US TV system, in MHz issystem, in MHz is

a. 41.25a. 41.25

b. 6b. 6

c. 4.5c. 4.5

d. 3.58d. 3.58

5. Interlacing is used in television to5. Interlacing is used in television to

a. produce the illusion of motiona. produce the illusion of motion

b. ensure that all the lines on the b. ensure that all the lines on the screen are scanned, not merely the screen are scanned, not merely the alternate onesalternate ones

c. simplify the vertical sync pulse c. simplify the vertical sync pulse traintrain

d. avoid flickerd. avoid flicker

5. Interlacing is used in television to5. Interlacing is used in television to

a. produce the illusion of motiona. produce the illusion of motion

b. ensure that all the lines on the b. ensure that all the lines on the screen are scanned, not merely the screen are scanned, not merely the alternate onesalternate ones

c. simplify the vertical sync pulse c. simplify the vertical sync pulse traintrain

d. avoid flickerd. avoid flicker

6. The signals sent by the TV 6. The signals sent by the TV transmitter to ensure correct transmitter to ensure correct scanning in the receiver are calledscanning in the receiver are called

a. synca. sync

b. chromab. chroma

c. luminancec. luminance

d. videod. video

6. The signals sent by the TV 6. The signals sent by the TV transmitter to ensure correct transmitter to ensure correct scanning in the receiver are calledscanning in the receiver are called

a. synca. sync

b. chromab. chroma

c. luminancec. luminance

d. videod. video

7. In the US color television system, 7. In the US color television system, the intercarrier frequency, in MHzthe intercarrier frequency, in MHz

a. 3.58a. 3.58

b. 3.579545b. 3.579545

c. 4.5c. 4.5

d. 45.75d. 45.75

7. In the US color television system, 7. In the US color television system, the intercarrier frequency, in MHzthe intercarrier frequency, in MHz

a. 3.58a. 3.58

b. 3.579545b. 3.579545

c. 4.5c. 4.5

d. 45.75d. 45.75

8. Indicate which voltages are not 8. Indicate which voltages are not found in the output of a normal found in the output of a normal monochrome receiver video monochrome receiver video detectordetector

a. synca. sync

b. videob. video

c. sweepc. sweep

d. soundd. sound

8. Indicate which voltages are not 8. Indicate which voltages are not found in the output of a normal found in the output of a normal monochrome receiver video monochrome receiver video detectordetector

a. synca. sync

b. videob. video

c. sweepc. sweep

d. soundd. sound

9. The carrier transmitted 1.25MHz 9. The carrier transmitted 1.25MHz above the bottom frequency in a above the bottom frequency in a US TV system channel is theUS TV system channel is the

a. sound carriera. sound carrier

b. chroma carrierb. chroma carrier

c. intercarrierc. intercarrier

d. picture carrierd. picture carrier

9. The carrier transmitted 1.25MHz 9. The carrier transmitted 1.25MHz above the bottom frequency in a above the bottom frequency in a US TV system channel is theUS TV system channel is the

a. sound carriera. sound carrier

b. chroma carrierb. chroma carrier

c. intercarrierc. intercarrier

d. picture carrierd. picture carrier

10. In television 4:3 represents the10. In television 4:3 represents the

a. interlace ratioa. interlace ratio

b. maximum horizontal deflectionb. maximum horizontal deflection

c. aspect ratioc. aspect ratio

d. ratio of the two diagonalsd. ratio of the two diagonals

10. In television 4:3 represents the10. In television 4:3 represents the

a. interlace ratioa. interlace ratio

b. maximum horizontal deflectionb. maximum horizontal deflection

c. aspect ratioc. aspect ratio

d. ratio of the two diagonalsd. ratio of the two diagonals

11. Equalizing pulses in TV are sent 11. Equalizing pulses in TV are sent duringduring

a. horizontal blankinga. horizontal blanking

b. vertical blankingb. vertical blanking

c. the serrationsc. the serrations

d. the horizontal retraced. the horizontal retrace

11. Equalizing pulses in TV are sent 11. Equalizing pulses in TV are sent duringduring

a. horizontal blankinga. horizontal blanking

b. vertical blankingb. vertical blanking

c. the serrationsc. the serrations

d. the horizontal retraced. the horizontal retrace

12. An odd number of lines per 12. An odd number of lines per frame forms part of every one of frame forms part of every one of the world’s TV system. This isthe world’s TV system. This is

a. done to assist interlacea. done to assist interlaceb. purely an accidentb. purely an accidentc. to ensure that line and frame c. to ensure that line and frame

frequencies can be obtained from frequencies can be obtained from the same original sourcethe same original source

d. done to minimize interference d. done to minimize interference with the chroma subcarrierswith the chroma subcarriers

12. An odd number of lines per 12. An odd number of lines per frame forms part of every one of frame forms part of every one of the world’s TV system. This isthe world’s TV system. This is

a. done to assist interlacea. done to assist interlaceb. purely an accidentb. purely an accidentc. to ensure that line and frame c. to ensure that line and frame

frequencies can be obtained from frequencies can be obtained from the same original sourcethe same original source

d. done to minimize interference d. done to minimize interference with the chroma subcarrierswith the chroma subcarriers

13. The function of the serrations in 13. The function of the serrations in the composite video waveform is tothe composite video waveform is to

a. equalized the charge in the a. equalized the charge in the integrator before the start of vertical integrator before the start of vertical retraceretrace

b. help vertical synchronizationb. help vertical synchronizationc. help horizontal synchronizationc. help horizontal synchronizationd. simplify the generation of vertical d. simplify the generation of vertical

sync pulsesync pulse

13. The function of the serrations in 13. The function of the serrations in the composite video waveform is tothe composite video waveform is to

a. equalized the charge in the a. equalized the charge in the integrator before the start of vertical integrator before the start of vertical retraceretrace

b. help vertical synchronizationb. help vertical synchronizationc. help horizontal synchronizationc. help horizontal synchronizationd. simplify the generation of vertical d. simplify the generation of vertical

sync pulsesync pulse

14. The width of the vertical pulse 14. The width of the vertical pulse in US TV system isin US TV system is

a. 21Ha. 21H

b. 3Hb. 3H

c. Hc. H

d. 0.5Hd. 0.5H

14. The width of the vertical pulse 14. The width of the vertical pulse in US TV system isin US TV system is

a. 21Ha. 21H

b. 3Hb. 3H

c. Hc. H

d. 0.5Hd. 0.5H

15. Indicate which of the following 15. Indicate which of the following frequencies will not be found in the frequencies will not be found in the output of a normal TV receiver output of a normal TV receiver tuner:tuner:

a. 4.5 MHza. 4.5 MHz

b. 41.25 MHzb. 41.25 MHz

c. 45.75 MHzc. 45.75 MHz

d. 42.17 MHzd. 42.17 MHz

15. Indicate which of the following 15. Indicate which of the following frequencies will not be found in the frequencies will not be found in the output of a normal TV receiver output of a normal TV receiver tuner:tuner:

a. 4.5 MHza. 4.5 MHz

b. 41.25 MHzb. 41.25 MHz

c. 45.75 MHzc. 45.75 MHz

d. 42.17 MHzd. 42.17 MHz

16. The video voltage applied to 16. The video voltage applied to the picture tube of a television the picture tube of a television receiver is fed inreceiver is fed in

a. between grid and grounda. between grid and ground

b. to the yokeb. to the yoke

c. to the anodec. to the anode

d. between the grid and cathoded. between the grid and cathode

16. The video voltage applied to 16. The video voltage applied to the picture tube of a television the picture tube of a television receiver is fed inreceiver is fed in

a. between grid and grounda. between grid and ground

b. to the yokeb. to the yoke

c. to the anodec. to the anode

d. between the grid and cathoded. between the grid and cathode

17. The circuit that separates the 17. The circuit that separates the sync pulse from the composite sync pulse from the composite video waveform isvideo waveform is

a. the keyed AGC amplifiera. the keyed AGC amplifier

b. a clipperb. a clipper

c. an integratorc. an integrator

d. a differentiatord. a differentiator

17. The circuit that separates the 17. The circuit that separates the sync pulse from the composite sync pulse from the composite video waveform isvideo waveform is

a. the keyed AGC amplifiera. the keyed AGC amplifier

b. a clipperb. a clipper

c. an integratorc. an integrator

d. a differentiatord. a differentiator

18. The output of the vertical 18. The output of the vertical amplifier, applied to the yoke in amplifier, applied to the yoke in the TV receiver, consist ofthe TV receiver, consist of

a. direct currenta. direct current

b. amplified vertical sync pulsesb. amplified vertical sync pulses

c. saw tooth voltagec. saw tooth voltage

d. a saw tooth currentd. a saw tooth current

18. The output of the vertical 18. The output of the vertical amplifier, applied to the yoke in amplifier, applied to the yoke in the TV receiver, consist ofthe TV receiver, consist of

a. direct currenta. direct current

b. amplified vertical sync pulsesb. amplified vertical sync pulses

c. saw tooth voltagec. saw tooth voltage

d. a saw tooth currentd. a saw tooth current

19. The HV anode supply for the 19. The HV anode supply for the picture tube for a TV receiver is picture tube for a TV receiver is generated in thegenerated in the

a. main transformera. main transformer

b. vertical output stageb. vertical output stage

c. horizontal output stagec. horizontal output stage

d. horizontal deflection staged. horizontal deflection stage

19. The HV anode supply for the 19. The HV anode supply for the picture tube for a TV receiver is picture tube for a TV receiver is generated in thegenerated in the

a. main transformera. main transformer

b. vertical output stageb. vertical output stage

c. horizontal output stagec. horizontal output stage

d. horizontal deflection staged. horizontal deflection stage

20. Another name for the horizontal 20. Another name for the horizontal retrace in a TV receiver is theretrace in a TV receiver is the

a. ringina. ringin

b. burstb. burst

c. damperc. damper

d. flybackd. flyback

20. Another name for the horizontal 20. Another name for the horizontal retrace in a TV receiver is theretrace in a TV receiver is the

a. ringina. ringin

b. burstb. burst

c. damperc. damper

d. flybackd. flyback

21. Indicate which of the following 21. Indicate which of the following signal is not transmitted in color signal is not transmitted in color TV:TV:

a. Ya. Y

b. Qb. Q

c. Rc. R

d. Id. I

21. Indicate which of the following 21. Indicate which of the following signal is not transmitted in color signal is not transmitted in color TV:TV:

a. Ya. Y

b. Qb. Q

c. Rc. R

d. Id. I

22. The Shadow mask in a color 22. The Shadow mask in a color picture tube is used topicture tube is used to

a. reduce x-ray emissiona. reduce x-ray emission

b. ensure that each beam hits only b. ensure that each beam hits only its own dotsits own dots

c. increase screen brightnessc. increase screen brightness

d. provide degaussing for the screend. provide degaussing for the screen

22. The Shadow mask in a color 22. The Shadow mask in a color picture tube is used topicture tube is used to

a. reduce x-ray emissiona. reduce x-ray emission

b. ensure that each beam hits only b. ensure that each beam hits only its own dotsits own dots

c. increase screen brightnessc. increase screen brightness

d. provide degaussing for the screend. provide degaussing for the screen

23. In a TV receiver the color killer23. In a TV receiver the color killera. cuts off the chroma stages during a. cuts off the chroma stages during

monochrome receptionmonochrome receptionb. ensure that no color is transmitted to b. ensure that no color is transmitted to

monochrome receivermonochrome receiverc. prevents color over loadingc. prevents color over loadingd. makes sure that the color burst is not d. makes sure that the color burst is not

mistaken for sync pulse, by cutting off mistaken for sync pulse, by cutting off reception during the back porchreception during the back porch

23. In a TV receiver the color killer23. In a TV receiver the color killera. cuts off the chroma stages during a. cuts off the chroma stages during

monochrome receptionmonochrome receptionb. ensure that no color is transmitted to b. ensure that no color is transmitted to

monochrome receivermonochrome receiverc. prevents color over loadingc. prevents color over loadingd. makes sure that the color burst is not d. makes sure that the color burst is not

mistaken for sync pulse, by cutting off mistaken for sync pulse, by cutting off reception during the back porchreception during the back porch

CHAPTER 18: CHAPTER 18: INTRODUCTION TO INTRODUCTION TO FIBER OPTIC FIBER OPTIC TECHNOLOGYTECHNOLOGY

1. What is the frequency limit of 1. What is the frequency limit of copper wire?copper wire?

a. Approximately 0.5 MHza. Approximately 0.5 MHz

b. Approximately 1.0 MHzb. Approximately 1.0 MHz

c. Approximately 40 GHzc. Approximately 40 GHz

d. None of the aboved. None of the above

1. What is the frequency limit of 1. What is the frequency limit of copper wire?copper wire?

a. Approximately 0.5 MHza. Approximately 0.5 MHz

b. Approximately 1.0 MHzb. Approximately 1.0 MHz

c. Approximately 40 GHzc. Approximately 40 GHz

d. None of the aboved. None of the above

2. Approximately what is the 2. Approximately what is the frequency limit of the optical frequency limit of the optical fiber?fiber?

a. 20 GHza. 20 GHz

b. 1 MHzb. 1 MHz

c. 100 MHzc. 100 MHz

d. 40 MHzd. 40 MHz

2. Approximately what is the 2. Approximately what is the frequency limit of the optical frequency limit of the optical fiber?fiber?

a. 20 GHz (no given answer)a. 20 GHz (no given answer)

b. 1 MHzb. 1 MHz

c. 100 MHzc. 100 MHz

d. 40 MHzd. 40 MHz

3. A single fiber can handle as 3. A single fiber can handle as many voice channels asmany voice channels as

a. A pair of copper conductorsa. A pair of copper conductors

b. A 1500-pair cableb. A 1500-pair cable

c. A 500-pair cablec. A 500-pair cable

d. A 1000- pair cabled. A 1000- pair cable

3. A single fiber can handle as 3. A single fiber can handle as many voice channels asmany voice channels as

a. A pair of copper conductorsa. A pair of copper conductors

b. A 1500-pair cableb. A 1500-pair cable

c. A 500-pair cablec. A 500-pair cable

d. A 1000- pair cabled. A 1000- pair cable

4. An incident ray can be defined as4. An incident ray can be defined as

a. A light ray reflected from a flat a. A light ray reflected from a flat surfacesurface

b. A light ray directed towards a b. A light ray directed towards a surfacesurface

c. A diffused light rayc. A diffused light ray

d. A light ray that happens d. A light ray that happens periodicallyperiodically

4. An incident ray can be defined as4. An incident ray can be defined as

a. A light ray reflected from a flat a. A light ray reflected from a flat surfacesurface

b. A light ray directed towards a b. A light ray directed towards a surfacesurface

c. A diffused light rayc. A diffused light ray

d. A light ray that happens d. A light ray that happens periodicallyperiodically

5. The term dispersion describes the 5. The term dispersion describes the process ofprocess of

a. Separating light into its component a. Separating light into its component frequenciesfrequencies

b. Reflecting light from a smooth b. Reflecting light from a smooth surfacesurface

c. The process by which light is c. The process by which light is absorbed by an uneven rough surfaceabsorbed by an uneven rough surface

d. Light scatteringd. Light scattering

5. The term dispersion describes the 5. The term dispersion describes the process ofprocess of

a. Separating light into its component a. Separating light into its component frequenciesfrequencies

b. Reflecting light from a smooth b. Reflecting light from a smooth surfacesurface

c. The process by which light is c. The process by which light is absorbed by an uneven rough surfaceabsorbed by an uneven rough surface

d. Light scatteringd. Light scattering

6. Which of the following terms describes 6. Which of the following terms describes the reason that light is refracted at the reason that light is refracted at different angles?different angles?

a. Photon energy changes with wavelengtha. Photon energy changes with wavelengthb. Light is refracted as a function of b. Light is refracted as a function of

surface smoothnesssurface smoothnessc. The angle is determined partly by a and c. The angle is determined partly by a and

bbd. The angle is determined by the index of d. The angle is determined by the index of

the materialsthe materials

6. Which of the following terms describes 6. Which of the following terms describes the reason that light is refracted at the reason that light is refracted at different angles?different angles?

a. Photon energy changes with wavelengtha. Photon energy changes with wavelengthb. Light is refracted as a function of b. Light is refracted as a function of

surface smoothnesssurface smoothnessc. The angle is determined partly by a and c. The angle is determined partly by a and

bbd. The angle is determined by the index of d. The angle is determined by the index of

the materialsthe materials

7. The term critical angle describes7. The term critical angle describes

a. The point at which light is refracteda. The point at which light is refracted

b. The point at which light becomes invisibleb. The point at which light becomes invisible

c. The point at which light has gone from the c. The point at which light has gone from the refractive mode to the reflective moderefractive mode to the reflective mode

d. The point at which light has crossed the d. The point at which light has crossed the boundary layers from one index to anotherboundary layers from one index to another

7. The term critical angle describes7. The term critical angle describes

a. The point at which light is refracteda. The point at which light is refracted

b. The point at which light becomes invisibleb. The point at which light becomes invisible

c. The point at which light has gone from the c. The point at which light has gone from the refractive mode to the reflective moderefractive mode to the reflective mode

d. The point at which light has crossed the d. The point at which light has crossed the boundary layers from one index to anotherboundary layers from one index to another

8. The cladding which surrounds the 8. The cladding which surrounds the fiber corefiber core

a. Is used to reduce optical interferencea. Is used to reduce optical interference

b. Is used to protect the fiberb. Is used to protect the fiber

c. Acts to help guide the light in the c. Acts to help guide the light in the corecore

d. Ensures that the refractive index d. Ensures that the refractive index remains constantremains constant

8. The cladding which surrounds the 8. The cladding which surrounds the fiber corefiber core

a. Is used to reduce optical interferencea. Is used to reduce optical interference

b. Is used to protect the fiberb. Is used to protect the fiber

c. Acts to help guide the light in the c. Acts to help guide the light in the corecore

d. Ensures that the refractive index d. Ensures that the refractive index remains constantremains constant

9. The reflective index number is9. The reflective index number is

a. A number which compares the a. A number which compares the transparency of a material with that of transparency of a material with that of airair

b. A number assigned by the b. A number assigned by the manufacturer to the fiber in questionmanufacturer to the fiber in question

c. A number which determines the core c. A number which determines the core diameterdiameter

d. A term for describing core elasticityd. A term for describing core elasticity

9. The reflective index number is9. The reflective index number is

a. A number which compares the a. A number which compares the transparency of a material with that of transparency of a material with that of airair

b. A number assigned by the b. A number assigned by the manufacturer to the fiber in questionmanufacturer to the fiber in question

c. A number which determines the core c. A number which determines the core diameterdiameter

d. A term for describing core elasticityd. A term for describing core elasticity

10. The terms single mode and 10. The terms single mode and multimode are best described asmultimode are best described as

a. The number of fibers placed into a a. The number of fibers placed into a fiber-optic cablefiber-optic cable

b. The number of voice channels b. The number of voice channels each fiber can supporteach fiber can support

c. The number of wavelengths each c. The number of wavelengths each fiber can supportfiber can support

d. The index numberd. The index number

10. The terms single mode and 10. The terms single mode and multimode are best described asmultimode are best described as

a. The number of fibers placed into a a. The number of fibers placed into a fiber-optic cablefiber-optic cable

b. The number of voice channels b. The number of voice channels each fiber can supporteach fiber can support

c. The number of wavelengths each c. The number of wavelengths each fiber can supportfiber can support

d. The index numberd. The index number

11. The higher the index number11. The higher the index number

a. The higher the speed of lighta. The higher the speed of light

b. The lower the speed of lightb. The lower the speed of light

c. Has no effect on the speed of c. Has no effect on the speed of lightlight

d. The shorter the wavelength d. The shorter the wavelength propagationpropagation

11. The higher the index number11. The higher the index number

a. The higher the speed of lighta. The higher the speed of light

b. The lower the speed of lightb. The lower the speed of light

c. Has no effect on the speed of c. Has no effect on the speed of lightlight

d. The shorter the wavelength d. The shorter the wavelength propagationpropagation

12. The three major groups in the 12. The three major groups in the optical system areoptical system are

a. The components, the data rate, and a. The components, the data rate, and the response timethe response time

b. The source, the link, and the receiverb. The source, the link, and the receiverc. The transmitter, the cable, and the c. The transmitter, the cable, and the

receiverreceiverd. The source, the link, and the d. The source, the link, and the

detectordetector

12. The three major groups in the 12. The three major groups in the optical system areoptical system are

a. The components, the data rate, and a. The components, the data rate, and the response timethe response time

b. The source, the link, and the receiverb. The source, the link, and the receiverc. The transmitter, the cable, and the c. The transmitter, the cable, and the

receiverreceiverd. The source, the link, and the d. The source, the link, and the

detectordetector

13. As light is coupled in a 13. As light is coupled in a multipoint reflective device, the multipoint reflective device, the power is reduce bypower is reduce by

a. 1.5 dBa. 1.5 dB

b. 0.1 dBb. 0.1 dB

c. 0.5 dBc. 0.5 dB

d. 0.001 dBd. 0.001 dB

13. As light is coupled in a 13. As light is coupled in a multipoint reflective device, the multipoint reflective device, the power is reduce bypower is reduce by

a. 1.5 dBa. 1.5 dB

b. 0.1 dBb. 0.1 dB

c. 0.5 dBc. 0.5 dB

d. 0.001 dBd. 0.001 dB

14. When connector losses, splice 14. When connector losses, splice losses, and coupler losses are losses, and coupler losses are added, what is the final limiting added, what is the final limiting factor?factor?

a. Source powera. Source power

b. Fiber attenuationb. Fiber attenuation

c. Connector and splice lossesc. Connector and splice losses

d. Detector sensitivityd. Detector sensitivity

14. When connector losses, splice 14. When connector losses, splice losses, and coupler losses are losses, and coupler losses are added, what is the final limiting added, what is the final limiting factor?factor?

a. Source powera. Source power

b. Fiber attenuationb. Fiber attenuation

c. Connector and splice lossesc. Connector and splice losses

d. Detector sensitivityd. Detector sensitivity

15. The term responsivity as it applies to a 15. The term responsivity as it applies to a light detector is best described aslight detector is best described as

a. The time required for the signal to go from a. The time required for the signal to go from 10 to 90 percent of maximum amplitude10 to 90 percent of maximum amplitude

b. The ratio of the diode output current to b. The ratio of the diode output current to optical input poweroptical input power

c. The ratio of output current to output powerc. The ratio of output current to output power

d. The ratio of output current to input currentd. The ratio of output current to input current

15. The term responsivity as it applies to a 15. The term responsivity as it applies to a light detector is best described aslight detector is best described as

a. The time required for the signal to go from a. The time required for the signal to go from 10 to 90 percent of maximum amplitude10 to 90 percent of maximum amplitude

b. The ratio of the diode output current to b. The ratio of the diode output current to optical input poweroptical input power

c. The ratio of output current to output powerc. The ratio of output current to output power

d. The ratio of output current to input currentd. The ratio of output current to input current

16. Loss comparisons between 16. Loss comparisons between fusion splices and mechanical fusion splices and mechanical splices aresplices are

a. 1:10a. 1:10

b. 10:1b. 10:1

c. 20:1c. 20:1

d. 1:20d. 1:20

16. Loss comparisons between 16. Loss comparisons between fusion splices and mechanical fusion splices and mechanical splices aresplices are

a. 1:10a. 1:10

b. 10:1b. 10:1

c. 20:1c. 20:1

d. 1:20d. 1:20

17. The mechanical splice is best 17. The mechanical splice is best suited forsuited for

a. Quicker installation under ideal a. Quicker installation under ideal conditionsconditions

b. Minimum attenuation lossesb. Minimum attenuation lossesc. Field service conditionsc. Field service conditionsd. Situations in which cost of d. Situations in which cost of

equipment is not a factorequipment is not a factor

17. The mechanical splice is best 17. The mechanical splice is best suited forsuited for

a. Quicker installation under ideal a. Quicker installation under ideal conditionsconditions

b. Minimum attenuation lossesb. Minimum attenuation lossesc. Field service conditionsc. Field service conditionsd. Situations in which cost of d. Situations in which cost of

equipment is not a factorequipment is not a factor

18. EMD is best described by which statement?18. EMD is best described by which statement?a. 70 percent of the core diameter and 70 a. 70 percent of the core diameter and 70

percent of the fiber NA should be filled with percent of the fiber NA should be filled with lightlight

b. 70 percent of the fiber diameter and 70 b. 70 percent of the fiber diameter and 70 percent of the cone of acceptance should be percent of the cone of acceptance should be filled with lightfilled with light

c. 70 percent of input light should be c. 70 percent of input light should be measured at the outputmeasured at the output

d. 70 percent of the unwanted wavelengths d. 70 percent of the unwanted wavelengths should be attenuated by the fibershould be attenuated by the fiber

18. EMD is best described by which statement?18. EMD is best described by which statement?a. 70 percent of the core diameter and 70 a. 70 percent of the core diameter and 70

percent of the fiber NA should be filled with percent of the fiber NA should be filled with lightlight

b. 70 percent of the fiber diameter and 70 b. 70 percent of the fiber diameter and 70 percent of the cone of acceptance should be percent of the cone of acceptance should be filled with lightfilled with light

c. 70 percent of input light should be c. 70 percent of input light should be measured at the outputmeasured at the output

d. 70 percent of the unwanted wavelengths d. 70 percent of the unwanted wavelengths should be attenuated by the fibershould be attenuated by the fiber

19. Which of the following cables 19. Which of the following cables will have the highest launch will have the highest launch power capabilitypower capability

a. 50/125/0.2a. 50/125/0.2

b. 85/125/0.275b. 85/125/0.275

c. 62.5/125/0.275c. 62.5/125/0.275

d. 100/140/0.3d. 100/140/0.3

19. Which of the following cables 19. Which of the following cables will have the highest launch will have the highest launch power capabilitypower capability

a. 50/125/0.2a. 50/125/0.2

b. 85/125/0.275b. 85/125/0.275

c. 62.5/125/0.275c. 62.5/125/0.275

d. 100/140/0.3d. 100/140/0.3

20. The term power budgeting refers to20. The term power budgeting refers toa. The cost of cables, connectors, a. The cost of cables, connectors,

equipment, and installationequipment, and installationb. The loss of power due to defective b. The loss of power due to defective

componentscomponentsc. The total power available minus the c. The total power available minus the

attenuation lossesattenuation lossesd. The comparative costs of fiber and d. The comparative costs of fiber and

copper installationscopper installations

20. The term power budgeting refers to20. The term power budgeting refers toa. The cost of cables, connectors, a. The cost of cables, connectors,

equipment, and installationequipment, and installationb. The loss of power due to defective b. The loss of power due to defective

componentscomponentsc. The total power available minus the c. The total power available minus the

attenuation lossesattenuation lossesd. The comparative costs of fiber and d. The comparative costs of fiber and

copper installationscopper installations