Kennedy Questions (Aaron Agoot)

Electronic Systems Electronic Systems and Technologyand TechnologyCompiled 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 transmitterb. in the channelb. in the channelc. in the information sourcec. in the information sourced. 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 transmitterb. in the channelb. in the channelc. in the information sourcec. in the information sourced. 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 usedb. separate the differing transmissionsb. separate the differing transmissionsc. ensure that intelligence may be c. ensure that intelligence may be

transmitted over long distancestransmitted over long distancesd. 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 usedb. separate the differing transmissionsb. separate the differing transmissionsc. ensure that intelligence may be c. ensure that intelligence may be

transmitted over long distancestransmitted over long distancesd. 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 energyb. predictable in characterb. predictable in characterc. present in the transmitterc. present in the transmitterd. 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 energyb. predictable in characterb. predictable in characterc. present in the transmitterc. present in the transmitterd. 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 groupb. frequency-modulated groupb. frequency-modulated groupc. superheterodyne groupc. superheterodyne groupd. 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 groupb. frequency-modulated groupb. frequency-modulated groupc. superheterodyne groupc. superheterodyne groupd. 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. decodingb. encodingb. encodingc. storagec. storaged. 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. decodingb. encodingb. encodingc. storagec. storaged. 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 communicationsb. single-sideband communicationb. single-sideband communicationc. television communicationsc. television communicationsd. 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 communicationsb. single-sideband communicationb. single-sideband communicationc. television communicationsc. television communicationsd. 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 noiseb. random noiseb. random noisec. impulse noisec. impulse noised. 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 noiseb. random noiseb. random noisec. impulse noisec. impulse noised. transit-time noised. transit-time noise

2. Indicate the false statement2. Indicate the false statementa. HF mixers are generally noisier than HF a. HF mixers are generally noisier than HF

amplifiersamplifiersb. Impulse noised voltage is independent b. Impulse noised voltage is independent

of the bandwidthof the bandwidthc. Thermal noise is independent of the c. Thermal noise is independent of the

frequency at which it is measuredfrequency at which it is measuredd. Industrial noise is usually of the impulse d. Industrial noise is usually of the impulse

typetype

2. Indicate the false statement2. Indicate the false statementa. HF mixers are generally noisier than HF a. HF mixers are generally noisier than HF

amplifiersamplifiersb. Impulse noised voltage is independent b. Impulse noised voltage is independent

of the bandwidthof the bandwidthc. Thermal noise is independent of the c. Thermal noise is independent of the

frequency at which it is measuredfrequency at which it is measuredd. Industrial noise is usually of the impulse d. Industrial noise is usually of the impulse

typetype

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. halvedb. quadrupledb. quadrupledc. doublec. doubled. 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. halvedb. quadrupledb. quadrupledc. doublec. doubled. 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 voltageb. Equivalent noise resistanceb. Equivalent noise resistancec. Noise temperaturec. Noise temperatured. 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 voltageb. Equivalent noise resistanceb. Equivalent noise resistancec. Noise temperaturec. Noise temperatured. 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 noiseb. cosmic noiseb. cosmic noisec. atmospheric noisec. atmospheric noised. 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 noiseb. cosmic noiseb. cosmic noisec. atmospheric noisec. atmospheric noised. 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 togenerated by a resistor is proportional to

a. its resistancea. its resistanceb. its temperatureb. its temperaturec. Boltzmann’s Constantc. Boltzmann’s Constantd. 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 togenerated by a resistor is proportional to

a. its resistancea. its resistanceb. its temperatureb. its temperaturec. Boltzmann’s Constantc. Boltzmann’s Constantd. 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 receiverb. noise generated in the transmitterb. noise generated in the transmitterc. externally generated noisec. externally generated noised. 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 receiverb. noise generated in the transmitterb. noise generated in the transmitterc. externally generated noisec. externally generated noised. 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 GHzb. below 20 MHzb. below 20 MHzc. between 20 to 120 MHzc. between 20 to 120 MHzd. 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 GHzb. below 20 MHzb. below 20 MHzc. between 20 to 120 MHzc. between 20 to 120 MHzd. 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 thatcalculations it must be remembered that

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 valuesc. calculations are based on average c. calculations are based on average

valuesvaluesd. 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 thatcalculations it must be remembered that

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 valuesc. calculations are based on average c. calculations are based on average

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

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

a. signal-to-noise ratioa. signal-to-noise ratiob. noise factorb. noise factorc. shot noisec. shot noised. thermal noise agitationd. thermal noise agitation

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

a. signal-to-noise ratioa. signal-to-noise ratiob. noise factorb. noise factorc. shot noisec. shot noised. 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 inadequate c. Noise in mixers is caused by inadequate image frequency rejectionimage 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 inadequate c. Noise in mixers is caused by inadequate image frequency rejectionimage 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 plate modulated class C amplifier is V, the maximum plate-cathode is 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 plate modulated class C amplifier is V, the maximum plate-cathode is 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 devicesb. harmonic devicesb. harmonic devicesc. class C amplifiersc. class C amplifiersd. 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 devicesb. harmonic devicesb. harmonic devicesc. class C amplifiersc. class C amplifiersd. 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 bethe percentage power saving will be

a. 50a. 50b. 150b. 150c. 100c. 100d. 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 bethe percentage power saving will be

a. 50a. 50b. 150b. 150c. 100c. 100d. 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 dampingb. prevent excessive grid currentb. prevent excessive grid currentc. prevent over modulationc. prevent over modulationd. 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 dampingb. prevent excessive grid currentb. prevent excessive grid currentc. prevent over modulationc. prevent over modulationd. 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 amplifierb. grid modulated class C amplifierb. grid modulated class C amplifierc. screen modulated class C c. screen modulated class C

amplifieramplifierd. 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 amplifierb. grid modulated class C amplifierb. grid modulated class C amplifierc. screen modulated class C c. screen modulated class C

amplifieramplifierd. 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. unchangedb. halvedb. halvedc. doubledc. doubledd. 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. unchangedb. halvedb. halvedc. doubledc. doubledd. increase by 50percentd. increase by 50percent

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

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 modulation over collector modulation of a transistor class C amplifierof a transistor class C amplifier

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

a. is 1a. is 1b. cannot be calculated unless the phase b. cannot be calculated unless the phase

relations are knownrelations are knownc. is 0.5c. is 0.5d. is 0.7d. is 0.7

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

a. is 1a. is 1b. cannot be calculated unless the phase b. cannot be calculated unless the phase

relations are knownrelations are knownc. is 0.5c. is 0.5d. 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 requires b. compared with other system it requires less transmitting powerless transmitting power

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

the necessary bandwidth for high fidelitythe necessary bandwidth for high 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 requires b. compared with other system it requires less transmitting powerless transmitting power

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

the necessary bandwidth for high fidelitythe necessary bandwidth for high 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. 1:3b. 1:2b. 1:2c. 2:3c. 2:3d. 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. 1:3b. 1:2b. 1:2c. 2:3c. 2:3d. 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 (J3E)c. Single-sideband, suppressed carrier (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 (J3E)c. Single-sideband, suppressed carrier (J3E)d. Double sideband, full carrier (A3E)d. Double sideband, full carrier (A3E)

3. Indicate which one of the following advantages 3. Indicate which one of the following advantages of the phase cancellation method of obtaining of the phase cancellation method of obtaining SSB over the filter method is false: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 advantages 3. Indicate which one of the following advantages of the phase cancellation method of obtaining of the phase cancellation method of obtaining SSB over the filter method is false: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. mechanicalb. RCb. RCc. LCc. LCd. 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. mechanicalb. RCb. RCc. LCc. LCd. 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 amplifierb. tuned modulatorb. tuned modulatorc. class B RF amplifierc. class B RF amplifierd. 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 amplifierb. tuned modulatorb. tuned modulatorc. class B RF amplifierc. class B RF amplifierd. 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. H3Eb. A3Eb. A3Ec. B8Ec. B8Ed. 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. H3Eb. A3Eb. A3Ec. B8Ec. B8Ed. 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 systemb. Phase shift methodb. Phase shift methodc. Third methodc. Third methodd. 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 systemb. Phase shift methodb. Phase shift methodc. Third methodc. Third methodd. Balance modulatord. Balance modulator

8. R3E modulation is sometimes used to8. R3E modulation is sometimes used toa. allow the receiver to have frequency a. allow the receiver to have frequency

synthesizersynthesizerb. simplify the frequency stability problem b. simplify the frequency stability problem

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

transmittedtransmittedd. reduce the bandwidth required for d. reduce the bandwidth required for

transmissiontransmission

8. R3E modulation is sometimes used to8. R3E modulation is sometimes used toa. allow the receiver to have frequency a. allow the receiver to have frequency

synthesizersynthesizerb. simplify the frequency stability problem b. simplify the frequency stability problem

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

transmittedtransmittedd. 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. ISBb. Carrier reinsertionb. Carrier reinsertionc. SSB with pilot carrierc. SSB with pilot carrierd. 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. ISBb. Carrier reinsertionb. Carrier reinsertionc. SSB with pilot carrierc. SSB with pilot carrierd. 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 broadcastingc. TV broadcastingc. TV broadcastingd. 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 broadcastingc. TV broadcastingc. TV broadcastingd. 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 time a. the discriminator must have a fast time constant to prevent demodulationconstant 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 time a. the discriminator must have a fast time constant to prevent demodulationconstant 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 depends b. the amplitude of any sideband depends on the modulation indexon 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 depends b. the amplitude of any sideband depends on the modulation indexon 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 system b. is too great to make the two system compatiblecompatible

c. lies in the poorer audio response of c. lies in the poorer audio response of the phase modulationthe 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 system b. is too great to make the two system compatiblecompatible

c. lies in the poorer audio response of c. lies in the poorer audio response of the phase modulationthe 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 usedc. Frequency multiplications must be usedd. 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 usedc. Frequency multiplications must be usedd. 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/3b. mfb. mfc. 3mfc. 3mfd. 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/3b. mfb. mfc. 3mfc. 3mfd. 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 its passed through a mixer, and has its frequency reduced fivefold. The 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 its passed through a mixer, and has its frequency reduced fivefold. The 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 frequencyb. amplifying the high audio b. amplifying the high audio

frequenciesfrequenciesc. preamplifying the whole audio bandc. preamplifying the whole audio bandd. converting the phase modulation to d. converting the phase modulation to

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 frequencyb. amplifying the high audio b. amplifying the high audio

frequenciesfrequenciesc. preamplifying the whole audio bandc. preamplifying the whole audio bandd. converting the phase modulation to d. converting the phase modulation to

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 providedb. Lower bandwidth is requiredb. Lower bandwidth is requiredc. The transmitted power is more usefulc. The transmitted power is more usefuld. 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 providedb. Lower bandwidth is requiredb. Lower bandwidth is requiredc. The transmitted power is more usefulc. The transmitted power is more usefuld. Less modulating power is required d. Less modulating power is required

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

a. Reactance FET modulatora. Reactance FET modulatorb. Varactor diodeb. Varactor diodec. Armstrong modulatorc. Armstrong modulatord. Reactance bipolar transistor d. Reactance bipolar transistor

modulatormodulator

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

a. Reactance FET modulatora. Reactance FET modulatorb. Varactor diodeb. Varactor diodec. Armstrong modulatorc. Armstrong modulatord. Reactance bipolar transistor d. Reactance bipolar transistor

modulatormodulator

12. In an FM stereo multiplex transmission, 12. In an FM stereo multiplex transmission, thethe

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 transmission, 12. In an FM stereo multiplex transmission, thethe

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 AGC3. In a radio receiver with simple AGCa. an increase in signal strength a. an increase in signal strength

produces more AGCproduces more AGCb. the audio stage gain is normally b. the audio stage gain is normally

controlled by the AGCcontrolled by the AGCc. the faster the AGC time constant, c. the faster the AGC time constant,

the more accurate the outputthe more accurate the outputd. the highest AGC voltage is d. the highest AGC voltage is

produced between stationsproduced between stations

3. In a radio receiver with simple AGC3. In a radio receiver with simple AGCa. an increase in signal strength a. an increase in signal strength

produces more AGCproduces more AGCb. the audio stage gain is normally b. the audio stage gain is normally

controlled by the AGCcontrolled by the AGCc. the faster the AGC time constant, c. the faster the AGC time constant,

the more accurate the outputthe more accurate the outputd. the highest AGC voltage is d. the highest AGC voltage is

produced between stationsproduced between stations

4. In broadcast super heterodyne receiver, 4. In broadcast super heterodyne receiver, thethe

a. local oscillator operates below the signal a. local oscillator operates below the signal frequencyfrequency

b. mixer input must be tuned to the signal b. mixer input must be tuned to the signal frequencyfrequency

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 receiver, 4. In broadcast super heterodyne receiver, thethe

a. local oscillator operates below the signal a. local oscillator operates below the signal frequencyfrequency

b. mixer input must be tuned to the signal b. mixer input must be tuned to the signal frequencyfrequency

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. squelchb. variable sensitivityb. variable sensitivityc. variable selectivityc. variable selectivityd. 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. squelchb. variable sensitivityb. variable sensitivityc. variable selectivityc. variable selectivityd. 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 isat 1200KHz. The image frequency is

a. 750KHza. 750KHzb. 900KHzb. 900KHzc. 1650KHzc. 1650KHzd. 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 isat 1200KHz. The image frequency is

a. 750KHza. 750KHzb. 900KHzb. 900KHzc. 1650KHzc. 1650KHzd. 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 from c. the output is twice that obtainable from

a similar phase discriminatora 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 are discriminator, except that the diodes are reversedreversed

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 from c. the output is twice that obtainable from

a similar phase discriminatora 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 are discriminator, except that the diodes are reversedreversed

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 oscillatorsc. it does not require crystal oscillatorsd. it is relatively free of spurious d. it is relatively free of spurious

frequencies frequencies

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 problemb. increase the frequency stability of the b. increase the frequency stability of the

synthesizersynthesizerc. reduce the number of decadesc. reduce the number of decadesd. 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 problemb. increase the frequency stability of the b. increase the frequency stability of the

synthesizersynthesizerc. reduce the number of decadesc. reduce the number of decadesd. 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 modulatorb. Product detectorb. Product detectorc. BFOc. BFOd. 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 modulatorb. Product detectorb. Product detectorc. BFOc. BFOd. 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 will amplifier in a transistor receiver, this will have the effect ofhave 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 receiverd. improving the selectivity of the receiver

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 will amplifier in a transistor receiver, this will have the effect ofhave 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 receiverd. improving the selectivity of the receiver

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 sensitivityc. inadequate selectivity at high frequenciesc. inadequate selectivity at high frequenciesd. 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 sensitivityc. inadequate selectivity at high frequenciesc. inadequate selectivity at high frequenciesd. 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 trackingb. permit better adjacent-channel rejectionb. permit better adjacent-channel rejectionc. increase the tuning range of the receiverc. increase the tuning range of the receiverd. 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 trackingb. permit better adjacent-channel rejectionb. permit better adjacent-channel rejectionc. increase the tuning range of the receiverc. increase the tuning range of the receiverd. 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. blockingb. double spottingb. double spottingc. diversity receptionc. diversity receptiond. 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. blockingb. double spottingb. double spottingc. diversity receptionc. diversity receptiond. sensitivityd. sensitivity

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

a. variable selectivitya. variable selectivityb. the padder capacitorb. the padder capacitorc. double spottingc. double spottingd. double conversion d. double conversion

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

a. variable selectivitya. variable selectivityb. the padder capacitorb. the padder capacitorc. double spottingc. double spottingd. 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 higher receiver is tuned to a frequency higher that the incoming frequencythat 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 higher receiver is tuned to a frequency higher that the incoming frequencythat 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 clippingb. poor AGC operationb. poor AGC operationc. negative-peak clippingc. negative-peak clippingd. 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 clippingb. poor AGC operationb. poor AGC operationc. negative-peak clippingc. negative-peak clippingd. 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 detectorb. diode balance modulatorb. diode balance modulatorc. bipolar transistor balance c. bipolar transistor balance

modulatormodulatord. 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 detectorb. diode balance modulatorb. diode balance modulatorc. bipolar transistor balance c. bipolar transistor balance

modulatormodulatord. 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 carriera. single sideband, suppressed carrierb. single sideband, reduced carrierb. single sideband, reduced carrierc. ISBc. ISBd. 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 carriera. single sideband, suppressed carrierb. single sideband, reduced carrierb. single sideband, reduced carrierc. ISBc. ISBd. 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 circuitb. a complex impedanceb. a complex impedancec. an open circuitc. an open circuitd. 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 circuitb. a complex impedanceb. a complex impedancec. an open circuitc. an open circuitd. 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 line3. The velocity factor of a transmission linea. depends on the dielectric constant of a. depends on the dielectric constant of

the material usedthe material usedb. increase the velocity along the b. increase the velocity along the

transmission linetransmission linec. is governed by the skin effectc. is governed by the skin effectd. is higher for a solid dielectric than for aird. is higher for a solid dielectric than for air

3. The velocity factor of a transmission line3. The velocity factor of a transmission linea. depends on the dielectric constant of a. depends on the dielectric constant of

the material usedthe material usedb. increase the velocity along the b. increase the velocity along the

transmission linetransmission linec. is governed by the skin effectc. is governed by the skin effectd. is higher for a solid dielectric than for aird. is higher for a solid dielectric than for air

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

a. a short circuited stuba. a short circuited stubb. an open circuited stubb. an open circuited stubc. a quarter wave linec. a quarter wave lined. 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 stubb. an open circuited stubb. an open circuited stubc. a quarter wave linec. a quarter wave lined. 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 connectb. made of transmission line with a b. made of transmission line with a

different characteristic impedancedifferent characteristic impedancec. liable to radiatec. liable to radiated. 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 connectb. made of transmission line with a b. made of transmission line with a

different characteristic impedancedifferent characteristic impedancec. liable to radiatec. liable to radiated. 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. balunb. broadband directional couplerb. broadband directional couplerc. double stubc. double stubd. 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. balunb. broadband directional couplerb. broadband directional couplerc. double stubc. double stubd. 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 couplingb. poor directivityb. poor directivityc. high SWRc. high SWRd. 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 couplingb. poor directivityb. poor directivityc. high SWRc. high SWRd. 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 lineb. balunb. balunc. directional couplerc. directional couplerd. 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 lineb. balunb. balunc. directional couplerc. directional couplerd. quarter wave transformerd. quarter wave transformer

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

a. (I^2)R, RL, and temperaturea. (I^2)R, RL, and temperatureb. Radiation, (I^2)R, and dielectric heatingb. Radiation, (I^2)R, and dielectric heatingc. Dielectric separation, insulation c. Dielectric separation, insulation

breakdown, and radiationbreakdown, and radiationd. Conductor heating, dielectric heating, d. Conductor heating, dielectric heating,

and radiation resistanceand radiation resistance

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

a. (I^2)R, RL, and temperaturea. (I^2)R, RL, and temperatureb. Radiation, (I^2)R, and dielectric heatingb. Radiation, (I^2)R, and dielectric heatingc. Dielectric separation, insulation c. Dielectric separation, insulation

breakdown, and radiationbreakdown, and radiationd. Conductor heating, dielectric heating, d. Conductor heating, dielectric heating,

and radiation resistanceand radiation resistance

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

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

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

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

d. An SWR measuring instrumentd. An SWR measuring instrument

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

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

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

c. A device used to measure transmission c. A device used to measure transmission line powerline 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. SIDsb. Fadingb. Fadingc. Atmospheric stormsc. Atmospheric stormsd. 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. SIDsb. Fadingb. Fadingc. Atmospheric stormsc. Atmospheric stormsd. Faraday Rotationd. Faraday Rotation

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

a. of the low powers requireda. of the low powers requiredb. the transmitting antennas are of b. the transmitting antennas are of

convenient sizeconvenient sizec. they are very reliablec. they are very reliabled. they penetrate the ionosphere d. they penetrate the ionosphere

easilyeasily

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

a. of the low powers requireda. of the low powers requiredb. the transmitting antennas are of b. the transmitting antennas are of

convenient sizeconvenient sizec. they are very reliablec. they are very reliabled. 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 area. absorbed by the F2 layera. absorbed by the F2 layerb. reflected by the D layerb. reflected by the D layerc. capable of use for long distance c. capable of use for long distance

communication on the mooncommunication on the moond. affected by the solar cycled. affected by the solar cycle

4. High frequency waves are4. High frequency waves area. absorbed by the F2 layera. absorbed by the F2 layerb. reflected by the D layerb. reflected by the D layerc. capable of use for long distance c. capable of use for long distance

communication on the mooncommunication on the moond. affected by the solar cycled. affected by the solar cycle

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

a. to avoid tiltinga. to avoid tiltingb. to prevent sky-wave and upper ray b. to prevent sky-wave and upper ray

interferenceinterferencec. to avoid the Faraday effectc. to avoid the Faraday effectd. so as not to exceed the critical d. so as not to exceed the critical

frequencyfrequency

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

a. to avoid tiltinga. to avoid tiltingb. to prevent sky-wave and upper ray b. to prevent sky-wave and upper ray

interferenceinterferencec. to avoid the Faraday effectc. to avoid the Faraday effectd. 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 ofbest solution seems to be the use of

a. a more directional antennasa. a more directional antennasb. broadband antennasb. broadband antennasc. frequency diversityc. frequency diversityd. 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 ofbest solution seems to be the use of

a. a more directional antennasa. a more directional antennasb. broadband antennasb. broadband antennasc. frequency diversityc. frequency diversityd. 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 called atmosphere than the other is called aa

a. windowa. windowb. critical frequencyb. critical frequencyc. gyro frequency rangec. gyro frequency ranged. 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 called atmosphere than the other is called aa

a. windowa. windowb. critical frequencyb. critical frequencyc. gyro frequency rangec. gyro frequency ranged. 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 wavesb. sky wavesb. sky wavesc. surface wavesc. surface wavesd. 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 wavesb. sky wavesb. sky wavesc. surface wavesc. surface wavesd. 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. HFb. VHFb. VHFc. UHFc. UHFd. 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. HFb. VHFb. VHFc. UHFc. UHFd. 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, polarization11. In electromagnetic waves, polarizationa. is caused by reflectiona. is caused by reflectionb. is due to the transverse nature of the b. is due to the transverse nature of the

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

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

antennaantenna

11. In electromagnetic waves, polarization11. In electromagnetic waves, polarizationa. is caused by reflectiona. is caused by reflectionb. is due to the transverse nature of the b. is due to the transverse nature of the

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

waveswavesd. 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. absorptionb. attenuationb. attenuationc. refractionc. refractiond. 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. absorptionb. attenuationb. attenuationc. refractionc. refractiond. 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 frequencyb. their distance from the transmitterb. their distance from the transmitterc. the polarization of the wavesc. the polarization of the wavesd. 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 frequencyb. their distance from the transmitterb. their distance from the transmitterc. the polarization of the wavesc. the polarization of the wavesd. 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 surfacec. encounter a perfectly conducting surfaced. 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 surfacec. encounter a perfectly conducting surfaced. pass through small slot in a conducting d. pass through small slot in a conducting

planeplane

15. Diffraction of electromagnetic wave15. Diffraction of electromagnetic wavea. is caused by reflections from the grounda. is caused by reflections from the groundb. arises only with the spherical wave b. arises only with the spherical wave

frontsfrontsc. will occur when the waves pass through c. will occur when the waves pass through

a large slota large slotd. 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 wavea. is caused by reflections from the grounda. is caused by reflections from the groundb. arises only with the spherical wave b. arises only with the spherical wave

frontsfrontsc. will occur when the waves pass through c. will occur when the waves pass through

a large slota large slotd. 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 effectb. ductingb. ductingc. troposheric scatterc. troposheric scatterd. 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 effectb. ductingb. ductingc. troposheric scatterc. troposheric scatterd. 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. troposcatterb. superrefractionb. superrefractionc. ionospheric refractionc. ionospheric refractiond. 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. troposcatterb. superrefractionb. superrefractionc. ionospheric refractionc. ionospheric refractiond. 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 matc. acts as an antenna arrayc. acts as an antenna arrayd. 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 matc. acts as an antenna arrayc. acts as an antenna arrayd. 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 antennab. folded dipoleb. folded dipolec. end fire arrayc. end fire arrayd. 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 antennab. folded dipoleb. folded dipolec. end fire arrayc. end fire arrayd. 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 hornb. folded dipoleb. folded dipolec. log-periodicc. log-periodicd. 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 hornb. folded dipoleb. folded dipolec. log-periodicc. log-periodicd. 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. biconicalb. hornb. hornc. helicalc. helicald. 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. biconicalb. hornb. hornc. helicalc. helicald. disconed. discone

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

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 antennad. rockiness of the ground itselfd. rockiness of the ground itself

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

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 antennad. 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 with b. to provide the output amplifier with

the correct load impedancethe 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 with b. to provide the output amplifier with

the correct load impedancethe 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. Disconeb. Folded dipoleb. Folded dipolec. Helicalc. Helicald. Marconid. Marconi

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

a. Disconea. Disconeb. Folded dipoleb. Folded dipolec. Helicalc. Helicald. 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 connectionb. provision of an earth for the antennab. provision of an earth for the antennac. protection of personnel working c. protection of personnel working

underneathunderneathd. 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 connectionb. provision of an earth for the antennab. provision of an earth for the antennac. protection of personnel working c. protection of personnel working

underneathunderneathd. 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 bandwidthb. parasitic elementsb. parasitic elementsc. folded dipolec. folded dipoled. 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 bandwidthb. parasitic elementsb. parasitic elementsc. folded dipolec. folded dipoled. high gaind. high gain

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

a. helicala. helicalb. small circular loopb. small circular loopc. parabolic reflectorc. parabolic reflectord. yagi–udad. yagi–uda

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

a. helicala. helicalb. small circular loopb. small circular loopc. parabolic reflectorc. parabolic reflectord. 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 dipoleb. isotropic antennab. isotropic antennac. elementary doubletc. elementary doubletd. 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 dipoleb. isotropic antennab. isotropic antennac. elementary doubletc. elementary doubletd. 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 heightb. bandwidthb. bandwidthc. beam widthc. beam widthd. 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 heightb. bandwidthb. bandwidthc. beam widthc. beam widthd. 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 reflectorc. reduce the size of the main reflectord. 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 reflectorc. reduce the size of the main reflectord. 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 lensb. increase the bandwidth of the lensb. increase the bandwidth of the lensc. permit pin point focusingc. permit pin point focusingd. 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 lensb. increase the bandwidth of the lensb. increase the bandwidth of the lensc. permit pin point focusingc. permit pin point focusingd. 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 polarizationb. maneuverabilityb. maneuverabilityc. broad bandwidthc. broad bandwidthd. 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 polarizationb. maneuverabilityb. maneuverabilityc. broad bandwidthc. broad bandwidthd. good front to back ratiod. good front to back ratio

16. The discone antenna is16. The discone antenna isa. a useful direction finding antennaa. a useful direction finding antennab. used as a radar receiving antennab. used as a radar receiving antennac. circularly polarized like other circular c. circularly polarized like other circular

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

16. The discone antenna is16. The discone antenna isa. a useful direction finding antennaa. a useful direction finding antennab. used as a radar receiving antennab. used as a radar receiving antennac. circularly polarized like other circular c. circularly polarized like other circular

antennasantennasd. 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 dipoleb. Log periodicb. Log periodicc. Disconec. Disconed. 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 dipoleb. Log periodicb. Log periodicc. Disconec. Disconed. 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 walls a. they travel along the broader walls of the guideof 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 walls a. they travel along the broader walls of the guideof 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 waveguidea. is greater than in free spacea. is greater than in free spaceb. depends only on the wave guide b. depends only on the wave guide

dimensions and the free space wavelengthdimensions and the free space wavelengthc. is inversely proportional to the phase c. is inversely proportional to the phase

velocityvelocityd. 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 waveguidea. is greater than in free spacea. is greater than in free spaceb. depends only on the wave guide b. depends only on the wave guide

dimensions and the free space wavelengthdimensions and the free space wavelengthc. is inversely proportional to the phase c. is inversely proportional to the phase

velocityvelocityd. 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 waveguides transmission line, 3GHz waveguides (indicate the false statement)(indicate the false statement)

a. are less lossya. are less lossyb. can carry high powersb. can carry high powersc. are less bulkyc. are less bulkyd. have lower attenuationd. have lower attenuation

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

a. are less lossya. are less lossyb. can carry high powersb. can carry high powersc. are less bulkyc. are less bulkyd. have lower attenuationd. have lower attenuation

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

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

6. When a particular mode is excited in 6. When a particular mode is excited in a waveguide, there appears an extra a waveguide, there appears an extra electric component, in the direction electric component, in the direction of propagation. The resulting mode isof propagation. The resulting 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 effectc. shortened because of the Doppler effectd. 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 effectc. shortened because of the Doppler effectd. greater than in the actual direction of d. greater than in the actual direction of

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

a. velocity of propagationa. velocity of propagationb. normal velocityb. normal velocityc. group velocityc. group velocityd. 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 waves conducting wall, electromagnetic waves require an apparent velocity greater than require an apparent velocity greater than the velocity of light in space. This is the velocity of light in space. This is calledcalled

a. velocity of propagationa. velocity of propagationb. normal velocityb. normal velocityc. group velocityc. group velocityd. phase velocityd. phase velocity

9. Indicate the false statement. When the free 9. Indicate the false statement. When the free space wavelength of a signal equals the space wavelength of a signal equals the cutoff waveguide of the guidecutoff 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 free 9. Indicate the false statement. When the free space wavelength of a signal equals the space wavelength of a signal equals the cutoff waveguide of the guidecutoff 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 in and no component of the electric field in the direction of propagation. The mode isthe direction of propagation. The mode 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 in and no component of the electric field in the direction of propagation. The mode isthe direction of propagation. The mode 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 couple 12. A choke flange may be used to couple two waveguidestwo waveguides

a. to help in alignment of the waveguidesa. to help in alignment of the waveguidesb. because it is simplier than any other b. because it is simplier than any other

joinjoinc. to compensate for discontinuities at the c. to compensate for discontinuities at the

joinjoind. to increase the bandwidth of the systemd. to increase the bandwidth of the system

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

a. to help in alignment of the waveguidesa. to help in alignment of the waveguidesb. because it is simplier than any other b. because it is simplier than any other

joinjoinc. to compensate for discontinuities at the c. to compensate for discontinuities at the

joinjoind. to increase the bandwidth of the systemd. to increase the bandwidth of the system

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. screwb. stubb. stubc. irisc. irisd. 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. screwb. stubb. stubc. irisc. irisd. plungerd. plunger

15. A piston attenuator is a15. A piston attenuator is aa. vane attenuatora. vane attenuatorb. waveguide below cutoffb. waveguide below cutoffc. mode filterc. mode filterd. 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 generationc. to reduce spurious mode generationd. 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 generationc. to reduce spurious mode generationd. to increase the bandwidth of the d. to increase the bandwidth of the

systemsystem

18. A ferrite is18. A ferrite isa. a non conductor with magnetic a. a non conductor with magnetic

propertiespropertiesb. an intermetallic compound with b. an intermetallic compound with

particularly good conductivityparticularly good conductivityc. an insulator which heavily attenuates c. an insulator which heavily attenuates

magnetic fieldsmagnetic fieldsd. a microwave semiconductor invented by d. a microwave semiconductor invented by

faradayfaraday

18. A ferrite is18. A ferrite isa. a non conductor with magnetic a. a non conductor with magnetic

propertiespropertiesb. an intermetallic compound with b. an intermetallic compound with

particularly good conductivityparticularly good conductivityc. an insulator which heavily attenuates c. an insulator which heavily attenuates

magnetic fieldsmagnetic fieldsd. a microwave semiconductor invented by d. a microwave semiconductor invented by

faradayfaraday

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

a. circulatora. circulatorb. isolatorb. isolatorc. garnetc. garnetd. phase shifterd. phase shifter

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

a. circulatora. circulatorb. isolatorb. isolatorc. garnetc. garnetd. 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 temperatureb. saturation magnetizationb. saturation magnetizationc. line widthc. line widthd. 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 temperatureb. saturation magnetizationb. saturation magnetizationc. line widthc. line widthd. gyromagnetic resonanced. gyromagnetic resonance

21. A PIN diode is21. A PIN diode isa. a metal semiconductor point a. a metal semiconductor point

contact diodecontact diodeb. a microwave mixer diodeb. a microwave mixer diodec. often used as a microwave detectorc. often used as a microwave detectord. suitable for the use as a microwave d. suitable for the use as a microwave

switchswitch

21. A PIN diode is21. A PIN diode isa. a metal semiconductor point a. a metal semiconductor point

contact diodecontact diodeb. a microwave mixer diodeb. a microwave mixer diodec. often used as a microwave detectorc. often used as a microwave detectord. suitable for the use as a microwave d. suitable for the use as a microwave

switchswitch

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 pulsed d. to increase the speed of the pulses in pulsed radarradar

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 pulsed d. to increase the speed of the pulses in pulsed radarradar

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. Ellipticalb. Flexibleb. Flexiblec. Coaxialc. Coaxiald. 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. Ellipticalb. Flexibleb. Flexiblec. Coaxialc. Coaxiald. 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. circularb. ridgedb. ridgedc. rectangularc. rectangulard. 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. circularb. ridgedb. ridgedc. rectangularc. rectangulard. flexibled. flexible

26. For low attenuation, the best 26. For low attenuation, the best transmission medium istransmission medium is

a. flexible waveguidea. flexible waveguideb. ridged waveguideb. ridged waveguidec. rectangular waveguidec. rectangular waveguided. 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 waveguideb. ridged waveguideb. ridged waveguidec. rectangular waveguidec. rectangular waveguided. 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 klystronb. coaxial magnetronb. coaxial magnetronc. traveling wave tube magnetronc. traveling wave tube magnetrond. 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 klystronb. coaxial magnetronb. coaxial magnetronc. traveling wave tube magnetronc. traveling wave tube magnetrond. 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. multicavityb. BWOb. BWOc. CFAc. CFAd. 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. multicavityb. BWOb. BWOc. CFAc. CFAd. 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 klystrona. is not a good low level amplifier because a. is not a good low level amplifier because

of noiseof noiseb. has a high repeller voltage to ensure a b. has a high repeller voltage to ensure a

rapid transit timerapid transit timec. is not suitable for pulsed operationc. is not suitable for pulsed operationd. 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 klystrona. is not a good low level amplifier because a. is not a good low level amplifier because

of noiseof noiseb. has a high repeller voltage to ensure a b. has a high repeller voltage to ensure a

rapid transit timerapid transit timec. is not suitable for pulsed operationc. is not suitable for pulsed operationd. 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 devicec. improve the power gainc. improve the power gaind. 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 devicec. improve the power gainc. improve the power gaind. 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 efficientb. has a greater bandwidthb. has a greater bandwidthc. has a higher number of modesc. has a higher number of modesd. 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 efficientb. has a greater bandwidthb. has a greater bandwidthc. has a higher number of modesc. has a higher number of modesd. 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 jumpingb. prevent cathode back heatingb. prevent cathode back heatingc. ensure bunchingc. ensure bunchingd. 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 jumpingb. prevent cathode back heatingb. prevent cathode back heatingc. ensure bunchingc. ensure bunchingd. 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 strapping 11. To avoid difficulties with strapping at high frequencies, the type of at high frequencies, the type of cavity structure used in the cavity structure used in the magnetron is themagnetron is the

a. hole and slota. hole and slotb. slotb. slotc. vanec. vaned. rising sund. rising sun

11. To avoid difficulties with strapping 11. To avoid difficulties with strapping at high frequencies, the type of at high frequencies, the type of cavity structure used in the cavity structure used in the magnetron is themagnetron is the

a. hole and slota. hole and slotb. slotb. slotc. vanec. vaned. 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 bunchingb. prevent oscillationsb. prevent oscillationsc. prevent saturationsc. prevent saturationsd. 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 bunchingb. prevent oscillationsb. prevent oscillationsc. prevent saturationsc. prevent saturationsd. 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 operationb. improve electron bunchingb. improve electron bunchingc. avoid the bulk of an electromagnetc. avoid the bulk of an electromagnetd. 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 operationb. improve electron bunchingb. improve electron bunchingc. avoid the bulk of an electromagnetc. avoid the bulk of an electromagnetd. 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 istransmitter output tube because it is

a. capable of longer duty cyclea. capable of longer duty cycleb. more efficient amplifierb. more efficient amplifierc. more broadbandc. more broadbandd. 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 istransmitter output tube because it is

a. capable of longer duty cyclea. capable of longer duty cycleb. more efficient amplifierb. more efficient amplifierc. more broadbandc. more broadbandd. 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 magnetronb. dither-tuned amplifierb. dither-tuned amplifierc. frequency- agile magnetronc. frequency- agile magnetrond. 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 magnetronb. dither-tuned amplifierb. dither-tuned amplifierc. frequency- agile magnetronc. frequency- agile magnetrond. 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 magnetb. coupled cavityb. coupled cavityc. helixc. helixd. 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 magnetb. coupled cavityb. coupled cavityc. helixc. helixd. 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 focusingb. provide attenuationb. provide attenuationc. improve bunchingc. improve bunchingd. 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 focusingb. provide attenuationb. provide attenuationc. improve bunchingc. improve bunchingd. 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 magnetronb. crossed field amplifierb. crossed field amplifierc. coaxial magnetronc. coaxial magnetrond. 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 magnetronb. crossed field amplifierb. crossed field amplifierc. coaxial magnetronc. coaxial magnetrond. 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 bandwidthc. because it cannot operate at room c. because it cannot operate at room

temperaturetemperatured. 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

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

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

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. microstripb. elliptical waveguideb. elliptical waveguidec. parallel wire linec. parallel wire lined. striplined. stripline

4. The transmission system using 4. The transmission system using two ground planes istwo ground planes is

a. microstripa. microstripb. elliptical waveguideb. elliptical waveguidec. parallel wire linec. parallel wire lined. 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 radiatec. higher isolation between adjacent c. higher isolation between adjacent

circuitscircuitsd. 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 radiatec. higher isolation between adjacent c. higher isolation between adjacent

circuitscircuitsd. higher Qd. higher Q

7. Surface acoustic waves 7. Surface acoustic waves propagate inpropagate in

a. gallium arsenidea. gallium arsenideb. indium phosphideb. indium phosphidec. striplinec. striplined. quartz crystald. quartz crystal

7. Surface acoustic waves 7. Surface acoustic waves propagate inpropagate in

a. gallium arsenidea. gallium arsenideb. indium phosphideb. indium phosphidec. striplinec. striplined. quartz crystald. quartz crystal

8. SAW devices may be used as8. SAW devices may be used asa. transmission media like striplinea. transmission media like striplineb. filtersb. filtersc. UHF amplifiersc. UHF amplifiersd. Oscillators at millimeter d. Oscillators at millimeter

9. Indicate the false statement. FETs 9. Indicate the false statement. FETs are preferred to bipolar transistor at are preferred to bipolar transistor at the high frequencies because theythe high frequencies because they

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 at are preferred to bipolar transistor at the high frequencies because theythe high frequencies because they

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 transistorb. a Gunn diodeb. a Gunn diodec. a step-recovery diodec. a step-recovery dioded. 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 transistorb. a Gunn diodeb. a Gunn diodec. a step-recovery diodec. a step-recovery dioded. 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. Varactorb. Gunnb. Gunnc. Schottky barrierc. Schottky barrierd. 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. Varactorb. Gunnb. Gunnc. Schottky barrierc. Schottky barrierd. 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. Backwardb. Gunnb. Gunnc. IMPATTc. IMPATTd. 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. Backwardb. Gunnb. Gunnc. IMPATTc. IMPATTd. 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 diodeb. schottky barrier diodeb. schottky barrier diodec. backward diodec. backward dioded. 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 diodeb. schottky barrier diodeb. schottky barrier diodec. backward diodec. backward dioded. 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. tunnelb. avalancheb. avalanchec. Gunnc. Gunnd. 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. tunnelb. avalancheb. avalanchec. Gunnc. Gunnd. IMPATTd. IMPATT

16. The transferred electron bulk 16. The transferred electron bulk effect occurs ineffect occurs in

a. germaniuma. germaniumb. gallium arsenideb. gallium arsenidec. siliconc. silicond. metal semiconductor, junctionsd. metal semiconductor, junctions

16. The transferred electron bulk 16. The transferred electron bulk effect occurs ineffect occurs in

a. germaniuma. germaniumb. gallium arsenideb. gallium arsenidec. siliconc. silicond. 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 to c. power gain of the transistor falls to

unityunityd. 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 to c. power gain of the transistor falls to

unityunityd. 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 largeb. collector current must be highb. collector current must be highc. base should be thinc. base should be thind. 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 largeb. collector current must be highb. collector current must be highc. base should be thinc. base should be thind. 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 tuningb. for frequency multiplicationb. for frequency multiplicationc. as an oscillatorc. as an oscillatord. 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 tuningb. for frequency multiplicationb. for frequency multiplicationc. as an oscillatorc. as an oscillatord. as a parametric amplifierd. as a parametric amplifier

20. If high order frequency multiplication is 20. If high order frequency multiplication is required from a diode multiplier,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 usedd. a large range of capacitance variation is d. a large range of capacitance variation is

neededneeded

20. If high order frequency multiplication is 20. If high order frequency multiplication is required from a diode multiplier,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 usedd. 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 amplifierb. degenerative amplifierb. degenerative amplifierc. lower sideband up converterc. lower sideband up converterd. 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 amplifierb. degenerative amplifierb. degenerative amplifierc. lower sideband up converterc. lower sideband up converterd. 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 idler and a pump frequency Fp. The idler frequency isfrequency is

a. Fia. Fib. 2Fib. 2Fic. Fi – Fpc. Fi – Fpd. 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 idler and a pump frequency Fp. The idler frequency isfrequency is

a. Fia. Fib. 2Fib. 2Fic. Fi – Fpc. Fi – Fpd. 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 gainb. reduce the number of varactor b. reduce the number of varactor

diodes requireddiodes requiredc. avoid the need for coolingc. avoid the need for coolingd. 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 gainb. reduce the number of varactor b. reduce the number of varactor

diodes requireddiodes requiredc. avoid the need for coolingc. avoid the need for coolingd. provide a greater bandwidthd. provide a greater bandwidth

24. A parametric amplifier sometimes uses 24. A parametric amplifier sometimes uses a circulator toa circulator to

a. prevent noise feedbacka. prevent noise feedbackb. 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 frequenciesc. separate the signal and idler frequenciesd. permit more efficient pumpingd. permit more efficient pumping

24. A parametric amplifier sometimes uses 24. A parametric amplifier sometimes uses a circulator toa circulator to

a. prevent noise feedbacka. prevent noise feedbackb. 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 frequenciesc. separate the signal and idler frequenciesd. 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 a c. uses a high doping level to provide a

narrow junctionnarrow 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 a c. uses a high doping level to provide a

narrow junctionnarrow 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

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

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 valley b. is available between the peak and valley pointspoints

c. is maximum at the valley pointc. is maximum at the valley pointd. 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 valley b. is available between the peak and valley pointspoints

c. is maximum at the valley pointc. is maximum at the valley pointd. may be improved by the use of reverse d. may be improved by the use of reverse

biasbias

29. The biggest advantage of gallium 29. The biggest advantage of gallium antimonide over germanium for antimonide over germanium for tunnel diode use is that the former tunnel diode use is that the former has ahas a

a. lower noisea. lower noiseb. higher ion mobilityb. higher ion mobilityc. larger voltage swingc. larger voltage swingd. simpler fabrication processd. simpler fabrication process

29. The biggest advantage of gallium 29. The biggest advantage of gallium antimonide over germanium for antimonide over germanium for tunnel diode use is that the former tunnel diode use is that the former has ahas a

a. lower noisea. lower noiseb. higher ion mobilityb. higher ion mobilityc. larger voltage swingc. larger voltage swingd. 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 junctiond. electron domains forming at the junctiond. electron domains forming at the junction

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 junctiond. electron domains forming at the junctiond. electron domains forming at the junction

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, which a. has suitable empty energy band, which silicon does not havesilicon does not have

b. has a higher ion mobilityb. has a higher ion mobilityc. has lower noise at the highest c. has lower noise at the highest

frequenciesfrequenciesd. 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, which a. has suitable empty energy band, which silicon does not havesilicon does not have

b. has a higher ion mobilityb. has a higher ion mobilityc. has lower noise at the highest c. has lower noise at the highest

frequenciesfrequenciesd. 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 noisec. inability to provide pulsed operationc. inability to provide pulsed operationd. 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 noisec. inability to provide pulsed operationc. inability to provide pulsed operationd. 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 inversionc. allow room temperature operationc. allow room temperature operationd. 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 inversionc. allow room temperature operationc. allow room temperature operationd. provide frequency adjustmentsd. provide frequency adjustments

34. The ruby maser has been 34. The ruby maser has been preferred to the ammonia maser for preferred to the ammonia maser for microwave amplification, because microwave amplification, because the former hasthe former has

a. a much greater bandwidtha. a much greater bandwidthb. a better frequency stabilityb. a better frequency stabilityc. a low noise figurec. a low noise figured. 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 for preferred to the ammonia maser for microwave amplification, because microwave amplification, because the former hasthe former has

a. a much greater bandwidtha. a much greater bandwidthb. a better frequency stabilityb. a better frequency stabilityc. a low noise figurec. a low noise figured. 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 both a re similar to each other in that both (false)(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 Kelvinc. must be cooled down to a few Kelvind. 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 both a re similar to each other in that both (false)(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 Kelvinc. must be cooled down to a few Kelvind. 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 astronomyb. satellite communicationsb. satellite communicationsc. radarc. radard. 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 astronomyb. satellite communicationsb. satellite communicationsc. radarc. radard. 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 pumpingb. needs no resonatorb. needs no resonatorc. is an oscillatorc. is an oscillatord. 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 pumpingb. needs no resonatorb. needs no resonatorc. is an oscillatorc. is an oscillatord. 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. infraredb. polarizedb. polarizedc. narrow beamc. narrow beamd. 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. infraredb. polarizedb. polarizedc. narrow beamc. narrow beamd. 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 coolingb. using Q spoilingb. using Q spoilingc. increasing the magnetic fieldc. increasing the magnetic fieldd. 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 coolingb. using Q spoilingb. using Q spoilingc. increasing the magnetic fieldc. increasing the magnetic fieldd. 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, tooptical fiber, rather that in open links, to

a. ensure that the beams does not spreada. ensure that the beams does not spreadb. prevent atmospheric interferenceb. prevent atmospheric interferencec. prevent interference by other lasersc. prevent interference by other lasersd. 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, tooptical fiber, rather that in open links, to

a. ensure that the beams does not spreada. ensure that the beams does not spreadb. prevent atmospheric interferenceb. prevent atmospheric interferencec. prevent interference by other lasersc. prevent interference by other lasersd. 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 outputb. higher power outputb. higher power outputc. lower costc. lower costd. 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 outputb. higher power outputb. higher power outputc. lower costc. lower costd. 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. morseb. baudotb. baudotc. CCITT-2c. CCITT-2d. 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. morseb. baudotb. baudotc. CCITT-2c. CCITT-2d. 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. 2b. Logb. Log10101616c. 8c. 8d. 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. 2b. Logb. Log10101616c. 8c. 8d. 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 redundantc. noise would introduce too many errorsc. noise would introduce too many errorsd. 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 redundantc. noise would introduce too many errorsc. noise would introduce too many errorsd. 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 channel transmission depends on the channel bandwidthbandwidth

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 channel transmission depends on the channel bandwidthbandwidth

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 reducedd. the signalling rate may be reduced

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 reducedd. the signalling rate may be reduced

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 keyingb. two tone modulationb. two tone modulationc. pulse code modulationc. pulse code modulationd. 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 keyingb. two tone modulationb. two tone modulationc. pulse code modulationc. pulse code modulationd. 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 multivibratorc. by integrating the signalc. by integrating the signald. 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 multivibratorc. by integrating the signalc. by integrating the signald. 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 modulationb. Pulse code modulationb. Pulse code modulationc. Pulse width modulationc. Pulse width modulationd. 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 modulationb. Pulse code modulationb. Pulse code modulationc. Pulse width modulationc. Pulse width modulationd. Pulse frequency modulationd. Pulse frequency modulation

9. Quantizing noise occurs in9. Quantizing noise occurs ina. time division multiplexa. time division multiplexb. frequency division multiplexb. frequency division multiplexc. pulse code modulationc. pulse code modulationd. 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 carrierb. Frequency modulationb. Frequency modulationc. Pulse position modulationc. Pulse position modulationd. 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 carrierb. Frequency modulationb. Frequency modulationc. Pulse position modulationc. Pulse position modulationd. 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 receiverd. 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 receiverd. 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 a b. maximum capacity of a channel with a given noise levelgiven noise level

c. maximum number of coding levels in a c. maximum number of coding levels in a channel with a given noise levelchannel with a given noise level

d. maximum number of quantizing levels d. maximum number of quantizing levels in a channel of a given bandwidthin a channel of a given bandwidth

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 a b. maximum capacity of a channel with a given noise levelgiven noise level

c. maximum number of coding levels in a c. maximum number of coding levels in a channel with a given noise levelchannel with a given noise level

d. maximum number of quantizing levels d. maximum number of quantizing levels in a channel of a given bandwidthin a channel of a given bandwidth

13. Indicate which of the following 13. Indicate which of the following pulse modulation system analog.pulse modulation system analog.

a. PCMa. PCMb. Differential PCMb. Differential PCMc. PWMc. PWMd. Deltad. Delta

13. Indicate which of the following 13. Indicate which of the following pulse modulation system analog.pulse modulation system analog.

a. PCMa. PCMb. Differential PCMb. Differential PCMc. PWMc. PWMd. 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 from c. to protect small signals in PCM from

quantizing distortionquantizing 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 from c. to protect small signals in PCM from

quantizing distortionquantizing distortiond. in the PCM receivers to overcome d. in the PCM receivers to overcome

15. The biggest disadvantage of PCM is15. The biggest disadvantage of PCM isa. its inability to handle analog signalsa. its inability to handle analog signalsb. the high error rate which its b. the high error rate which its

quantizing noise introducesquantizing noise introducesc. its incompatibility with TDMc. its incompatibility with TDMd. 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 isa. its inability to handle analog signalsa. its inability to handle analog signalsb. the high error rate which its b. the high error rate which its

quantizing noise introducesquantizing noise introducesc. its incompatibility with TDMc. its incompatibility with TDMd. 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 signalsa. do not provide a continuous set a. do not provide a continuous set

of valuesof valuesb. present values as discrete stepsb. present values as discrete stepsc. can utilized decimal or binary c. can utilized decimal or binary

systemssystemsd. all of the aboved. all of the above

1. Digital signals1. Digital signalsa. do not provide a continuous set a. do not provide a continuous set

of valuesof valuesb. present values as discrete stepsb. present values as discrete stepsc. can utilized decimal or binary c. can utilized decimal or binary

systemssystemsd. 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 computerb. development of the Hollerith codeb. development of the Hollerith codec. development of the transistorc. development of the transistord. development of the disk drives for d. development of the disk drives for

data storagedata 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 computerb. development of the Hollerith codeb. development of the Hollerith codec. development of the transistorc. development of the transistord. development of the disk drives for d. development of the disk drives for

data storagedata storage

3. The baud rate3. The baud ratea. is always equal to the bit transfer a. is always equal to the bit transfer

raterateb. is equal to twice the bandwidth of b. is equal to twice the bandwidth of

an ideal channelan ideal channelc. is not equal to the signaling ratec. is not equal to the signaling rated. 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 ratea. is always equal to the bit transfer a. is always equal to the bit transfer

raterateb. is equal to twice the bandwidth of b. is equal to twice the bandwidth of

an ideal channelan ideal channelc. is not equal to the signaling ratec. is not equal to the signaling rated. 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 Lawa. refers to distortiona. refers to distortionb. defines bandwidthb. defines bandwidthc. describes signalling ratesc. describes signalling ratesd. refers to noised. refers to noise

5. The code which provides parity 5. The code which provides parity check ischeck is

a. Baudota. Baudotb. ASCIIb. ASCIIc. EBCDICc. EBCDICd. CCITT-2d. CCITT-2

5. The code which provides parity 5. The code which provides parity check ischeck is

a. Baudota. Baudotb. ASCIIb. ASCIIc. EBCDICc. EBCDICd. 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 signalb. requiring retransmission of the entire signalc. requiring no part pf the signal to be c. requiring no part pf the signal to be

retransmittedretransmittedd. 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 signalb. requiring retransmission of the entire signalc. requiring no part pf the signal to be c. requiring no part pf the signal to be

retransmittedretransmittedd. using parity to correct the errors in all d. using parity to correct the errors in all

casescases

7. Full duplex operation7. Full duplex operationa. requires two pairs of cablesa. requires two pairs of cablesb. can transfer data in both b. can transfer data in both

directions at oncedirections at oncec. requires modems at both ends of c. requires modems at both ends of

the circuitthe circuitd. all of the aboved. all of the above

7. Full duplex operation7. Full duplex operationa. requires two pairs of cablesa. requires two pairs of cablesb. can transfer data in both b. can transfer data in both

directions at oncedirections at oncec. requires modems at both ends of c. requires modems at both ends of

the circuitthe circuitd. all of the aboved. all of the above

8. The RS-232 interface8. The RS-232 interfacea. interconnects data sets and a. interconnects data sets and

transmission circuitstransmission circuitsb. uses several different connectorsb. uses several different connectorsc. 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 interfacea. interconnects data sets and a. interconnects data sets and

transmission circuitstransmission circuitsb. uses several different connectorsb. uses several different connectorsc. 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 systemsa. improve the efficiency of the a. improve the efficiency of the

data transferdata transferb. are not used in data systemb. are not used in data systemc. require additional linesc. require additional linesd. are limited to small data d. are limited to small data

networksnetworks

9. Switching systems9. Switching systemsa. improve the efficiency of the a. improve the efficiency of the

data transferdata transferb. are not used in data systemb. are not used in data systemc. require additional linesc. require additional linesd. 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 secondb. Baud rateb. Baud ratec. Bits per secondc. Bits per secondd. 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 secondb. Baud rateb. Baud ratec. Bits per secondc. Bits per secondd. 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 cablesb. repeater amplifiersb. repeater amplifiersc. HF radioc. HF radiod. 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 cablesb. repeater amplifiersb. repeater amplifiersc. HF radioc. HF radiod. 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 multiplexb. Time division multiplexb. Time division multiplexc. A groupc. A groupd. 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 multiplexb. Time division multiplexb. Time division multiplexc. A groupc. A groupd. A super groupd. A super group

3. Basic group B3. Basic group Ba. occupies the frequency range a. occupies the frequency range

from 60 to 108 KHzfrom 60 to 108 KHzb. consist of erect channels onlyb. consist of erect channels onlyc. is formed at the group c. is formed at the group

translating equipmenttranslating equipmentd. consist of five super groupd. consist of five super group

3. Basic group B3. Basic group Ba. occupies the frequency range a. occupies the frequency range

from 60 to 108 KHzfrom 60 to 108 KHzb. consist of erect channels onlyb. consist of erect channels onlyc. is formed at the group c. is formed at the group

translating equipmenttranslating equipmentd. 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 for a. whether separate tubes are used for the two directions of transmissionthe two directions of transmission

b. the bandwidth of the systemb. the bandwidth of the systemc. the number of coaxial cables in the c. the number of coaxial cables in the

tubetubed. 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 for a. whether separate tubes are used for the two directions of transmissionthe two directions of transmission

b. the bandwidth of the systemb. the bandwidth of the systemc. the number of coaxial cables in the c. the number of coaxial cables in the

tubetubed. the separation of the equalizersd. the separation of the equalizers

6. Super group pilot is6. Super group pilot isa. applied at each multiplexing baya. applied at each multiplexing bayb. used to regulate the gain of b. used to regulate the gain of

individual repeatersindividual repeatersc. applied at each adjustable c. applied at each adjustable

equalizerequalizerd. fed in at a GTEd. fed in at a GTE

6. Super group pilot is6. Super group pilot isa. applied at each multiplexing baya. applied at each multiplexing bayb. used to regulate the gain of b. used to regulate the gain of

individual repeatersindividual repeatersc. applied at each adjustable c. applied at each adjustable

equalizerequalizerd. 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 attenuationb. because of output power limitationsb. because of output power limitationsc. because of earths curvaturec. because of earths curvatured. 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 attenuationb. because of output power limitationsb. because of output power limitationsc. because of earths curvaturec. because of earths curvatured. 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

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

9. Armored submarine cable is used9. Armored submarine cable is useda. to protect the cable at great depthsa. to protect the cable at great depthsb. to prevent inadvertent ploughing in b. to prevent inadvertent ploughing in

of the cableof 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 depthsa. to protect the cable at great depthsb. to prevent inadvertent ploughing in b. to prevent inadvertent ploughing in

of the cableof 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 regulatorb. filters for two directions of transmissionb. filters for two directions of transmissionc. multiplexing and demultiplexing c. multiplexing and demultiplexing

equipmentequipmentd. pilot inject and pilot extract equipmentd. pilot inject and pilot extract equipment

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 regulatorb. filters for two directions of transmissionb. filters for two directions of transmissionc. multiplexing and demultiplexing c. multiplexing and demultiplexing

equipmentequipmentd. pilot inject and pilot extract equipmentd. pilot inject and pilot extract equipment

11. Geostationary satellite11. Geostationary satellitea. 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 periodc. appears stationary above the Earth’s c. appears stationary above the Earth’s

magnetic polesmagnetic polesd. 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 satellitea. 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 periodc. appears stationary above the Earth’s c. appears stationary above the Earth’s

magnetic polesmagnetic polesd. 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. Comsatb. Domsatb. Domsatc. Marisatc. Marisatd. Intelsatd. Intelsat

13. Satellite used for inter 13. Satellite used for inter continental communications are continental communications are known asknown as

a. Comsata. Comsatb. Domsatb. Domsatc. Marisatc. Marisatd. 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 digitsb. access digitsb. access digitsc. area codesc. area codesd. 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 digitsb. access digitsb. access digitsc. area codesc. area codesd. central office codesd. central office codes

15. Telephone traffic is measured15. Telephone traffic is measureda. with echo cancellersa. with echo cancellersb. by their relative congestionsb. by their relative congestionsc. in terms of the grade of servicesc. in terms of the grade of servicesd. 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 gatesb. Bandpass filterb. Bandpass filterc. Differentiationc. Differentiationd. 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

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

18. Higher order TDM levels are 18. Higher order TDM levels are obtained byobtained by

a. dividing pulse widthsa. dividing pulse widthsb. using the a-lawb. using the a-lawc. using the u-lawc. using the u-lawd. 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 widthsb. using the a-lawb. using the a-lawc. using the u-lawc. using the u-lawd. 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. impuritiesb. microbendingb. microbendingc. attenuation in the glassc. attenuation in the glassd. 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. impuritiesb. microbendingb. microbendingc. attenuation in the glassc. attenuation in the glassd. 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 0.85umb. the attenuation is higher than at 1.3umb. the attenuation is higher than at 1.3umc. suitable laser devices have not yet been c. suitable laser devices have not yet been

developeddevelopedd. 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 0.85umb. the attenuation is higher than at 1.3umb. the attenuation is higher than at 1.3umc. suitable laser devices have not yet been c. suitable laser devices have not yet been

developeddevelopedd. 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-7b. INTELSAT Vb. INTELSAT Vc. ATLANTISc. ATLANTISd. 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-7b. INTELSAT Vb. INTELSAT Vc. ATLANTISc. ATLANTISd. 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. INTELSATb. COMSATb. COMSATc. TELSATc. TELSATd. 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. INTELSATb. COMSATb. COMSATc. TELSATc. TELSATd. 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 diameter 3. If the ratio of the antenna diameter to the wavelength in a radar system to the wavelength in a radar system is high this will result in (false)is high this will result in (false)

a. large maximum rangea. large maximum rangeb. good target discriminationb. good target discriminationc. difficult target acquisitionc. difficult target acquisitiond. increased capture aread. increased capture area

3. If the ratio of the antenna diameter 3. If the ratio of the antenna diameter to the wavelength in a radar system to the wavelength in a radar system is high this will result in (false)is high this will result in (false)

a. large maximum rangea. large maximum rangeb. good target discriminationb. good target discriminationc. difficult target acquisitionc. difficult target acquisitiond. 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 usedb. may be reduced by special coating of b. may be reduced by special coating of

the targetthe targetc. depends on the aspect of a target, if this c. depends on the aspect of a target, if this

is nonsphericalis nonsphericald. 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 usedb. may be reduced by special coating of b. may be reduced by special coating of

the targetthe targetc. depends on the aspect of a target, if this c. depends on the aspect of a target, if this

is nonsphericalis nonsphericald. 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 widthb. pulse repetition frequencyb. pulse repetition frequencyc. pulse intervalc. pulse intervald. square root of the peak transmitted d. square root of the peak transmitted

powerpower

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 widthb. pulse repetition frequencyb. pulse repetition frequencyc. pulse intervalc. pulse intervald. square root of the peak transmitted d. square root of the peak transmitted

powerpower

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. noddingb. spiralb. spiralc. conicalc. conicald. 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. noddingb. spiralb. spiralc. conicalc. conicald. 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 switchingb. sequential lobbingb. sequential lobbingc. conical scanningc. conical scanningd. 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 switchingb. sequential lobbingb. sequential lobbingc. conical scanningc. conical scanningd. 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 velocityb. it does not give the target rangeb. it does not give the target rangec. a transponder is required at the c. a transponder is required at the

targettargetd. 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 velocityb. it does not give the target rangeb. it does not give the target rangec. a transponder is required at the c. a transponder is required at the

targettargetd. it does not give the target positiond. it does not give the target position

12. A scope displays12. A scope displaysa. the target position and rangea. the target position and rangeb. the target range, but not positionb. the target range, but not positionc. the target position, but not the c. the target position, but not the

rangeranged. neither range nor position, but d. neither range nor position, but

only velocityonly velocity

12. A scope displays12. A scope displaysa. the target position and rangea. the target position and rangeb. the target range, but not positionb. the target range, but not positionc. the target position, but not the c. the target position, but not the

rangeranged. 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 PPIb. the MTI systemb. the MTI systemc. FM radarc. FM radard. 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 PPIb. the MTI systemb. the MTI systemc. FM radarc. FM radard. 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 frequencyb. transmitted frequencyb. transmitted frequencyc. received frequencyc. received frequencyd. 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 frequencyb. transmitted frequencyb. transmitted frequencyc. received frequencyc. received frequencyd. pulse repetition frequencyd. pulse repetition frequency

15. The function of the quartz delay line in 15. The function of the quartz delay line in an MTI radar is toan 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 in 15. The function of the quartz delay line in an MTI radar is toan 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 frequencyb. Vary the PRFb. Vary the PRFc. Use monopulsec. Use monopulsed. 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 frequencyb. Vary the PRFb. Vary the PRFc. Use monopulsec. Use monopulsed. 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 identificationb. navigationb. navigationc. very significant extension of the c. very significant extension of the

maximum rangemaximum ranged. 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 identificationb. navigationb. navigationc. very significant extension of the c. very significant extension of the

maximum rangemaximum ranged. 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 scanningb. ability to tract and scan simultaneouslyb. ability to tract and scan simultaneouslyc. circuit simplicityc. circuit simplicityd. 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 scanningb. ability to tract and scan simultaneouslyb. ability to tract and scan simultaneouslyc. circuit simplicityc. circuit simplicityd. 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 ½b. 525b. 525c. 30c. 30d. 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 ½b. 525b. 525c. 30c. 30d. 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. 60b. 262 ½b. 262 ½c. 4.5c. 4.5d. 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. 60b. 262 ½b. 262 ½c. 4.5c. 4.5d. 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. 31500b. 15750b. 15750c. 262 ½c. 262 ½d. 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. 31500b. 15750b. 15750c. 262 ½c. 262 ½d. 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. 41.25b. 6b. 6c. 4.5c. 4.5d. 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. 41.25b. 6b. 6c. 4.5c. 4.5d. 3.58d. 3.58

5. Interlacing is used in television to5. Interlacing is used in television toa. produce the illusion of motiona. produce the illusion of motionb. 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 trainc. simplify the vertical sync pulse traind. avoid flickerd. avoid flicker

5. Interlacing is used in television to5. Interlacing is used in television toa. produce the illusion of motiona. produce the illusion of motionb. 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 trainc. simplify the vertical sync pulse traind. 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. syncb. chromab. chromac. luminancec. luminanced. 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. syncb. chromab. chromac. luminancec. luminanced. 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. 3.58b. 3.579545b. 3.579545c. 4.5c. 4.5d. 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. 3.58b. 3.579545b. 3.579545c. 4.5c. 4.5d. 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 detectormonochrome receiver video detector

a. synca. syncb. videob. videoc. sweepc. sweepd. 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 detectormonochrome receiver video detector

a. synca. syncb. videob. videoc. sweepc. sweepd. 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 carrierb. chroma carrierb. chroma carrierc. intercarrierc. intercarrierd. 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 carrierb. chroma carrierb. chroma carrierc. intercarrierc. intercarrierd. picture carrierd. picture carrier

10. In television 4:3 represents the10. In television 4:3 represents thea. interlace ratioa. interlace ratiob. maximum horizontal deflectionb. maximum horizontal deflectionc. aspect ratioc. aspect ratiod. 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 blankingb. vertical blankingb. vertical blankingc. the serrationsc. the serrationsd. 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 blankingb. vertical blankingb. vertical blankingc. the serrationsc. the serrationsd. the horizontal retraced. the horizontal retrace

12. An odd number of lines per frame 12. An odd number of lines per frame forms part of every one of the forms part of every one of the world’s TV system. This isworld’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 with d. done to minimize interference with the chroma subcarriersthe chroma subcarriers

12. An odd number of lines per frame 12. An odd number of lines per frame forms part of every one of the forms part of every one of the world’s TV system. This isworld’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 with d. done to minimize interference with the chroma subcarriersthe 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. 21Hb. 3Hb. 3Hc. Hc. Hd. 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. 21Hb. 3Hb. 3Hc. Hc. Hd. 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 MHzb. 41.25 MHzb. 41.25 MHzc. 45.75 MHzc. 45.75 MHzd. 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 MHzb. 41.25 MHzb. 41.25 MHzc. 45.75 MHzc. 45.75 MHzd. 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 groundb. to the yokeb. to the yokec. to the anodec. to the anoded. 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 groundb. to the yokeb. to the yokec. to the anodec. to the anoded. 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 amplifierb. a clipperb. a clipperc. an integratorc. an integratord. 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 amplifierb. a clipperb. a clipperc. an integratorc. an integratord. 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 currentb. amplified vertical sync pulsesb. amplified vertical sync pulsesc. saw tooth voltagec. saw tooth voltaged. 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 currentb. amplified vertical sync pulsesb. amplified vertical sync pulsesc. saw tooth voltagec. saw tooth voltaged. 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 transformerb. vertical output stageb. vertical output stagec. horizontal output stagec. horizontal output staged. 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 transformerb. vertical output stageb. vertical output stagec. horizontal output stagec. horizontal output staged. 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. ringinb. burstb. burstc. damperc. damperd. 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. ringinb. burstb. burstc. damperc. damperd. 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. Yb. Qb. Qc. Rc. Rd. 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. Yb. Qb. Qc. Rc. Rd. 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 emissionb. ensure that each beam hits only b. ensure that each beam hits only

its own dotsits own dotsc. increase screen brightnessc. increase screen brightnessd. 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 emissionb. ensure that each beam hits only b. ensure that each beam hits only

its own dotsits own dotsc. increase screen brightnessc. increase screen brightnessd. 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 MHzb. Approximately 1.0 MHzb. Approximately 1.0 MHzc. Approximately 40 GHzc. Approximately 40 GHzd. 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 MHzb. Approximately 1.0 MHzb. Approximately 1.0 MHzc. Approximately 40 GHzc. Approximately 40 GHzd. 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 GHzb. 1 MHzb. 1 MHzc. 100 MHzc. 100 MHzd. 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 MHzc. 100 MHzc. 100 MHzd. 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 conductorsb. A 1500-pair cableb. A 1500-pair cablec. A 500-pair cablec. A 500-pair cabled. 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 conductorsb. A 1500-pair cableb. A 1500-pair cablec. A 500-pair cablec. A 500-pair cabled. A 1000- pair cabled. A 1000- pair cable

4. An incident ray can be defined as4. An incident ray can be defined asa. A light ray reflected from a flat a. A light ray reflected from a flat

surfacesurfaceb. A light ray directed towards a b. A light ray directed towards a

surfacesurfacec. A diffused light rayc. A diffused light rayd. A light ray that happens periodicallyd. A light ray that happens periodically

4. An incident ray can be defined as4. An incident ray can be defined asa. A light ray reflected from a flat a. A light ray reflected from a flat

surfacesurfaceb. A light ray directed towards a b. A light ray directed towards a

surfacesurfacec. A diffused light rayc. A diffused light rayd. A light ray that happens periodicallyd. A light ray that happens periodically

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 surface b. Light is refracted as a function of surface

smoothnesssmoothnessc. The angle is determined partly by a and bc. The angle is determined partly by a and bd. 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 surface b. Light is refracted as a function of surface

smoothnesssmoothnessc. The angle is determined partly by a and bc. The angle is determined partly by a and bd. 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 describesa. The point at which light is refracteda. The point at which light is refractedb. The point at which light becomes invisibleb. The point at which light becomes invisiblec. 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 moded. 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 describesa. The point at which light is refracteda. The point at which light is refractedb. The point at which light becomes invisibleb. The point at which light becomes invisiblec. 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 moded. 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 interferenceb. Is used to protect the fiberb. Is used to protect the fiberc. Acts to help guide the light in the c. Acts to help guide the light in the

corecored. 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 interferenceb. Is used to protect the fiberb. Is used to protect the fiberc. Acts to help guide the light in the c. Acts to help guide the light in the

corecored. Ensures that the refractive index d. Ensures that the refractive index

remains constantremains constant

9. The reflective index number is9. The reflective index number isa. 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 manufacturer b. A number assigned by the manufacturer to the fiber in questionto 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 isa. 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 manufacturer b. A number assigned by the manufacturer to the fiber in questionto 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 each b. The number of voice channels each fiber can supportfiber 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 each b. The number of voice channels each fiber can supportfiber 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 numbera. The higher the speed of lighta. The higher the speed of lightb. The lower the speed of lightb. The lower the speed of lightc. Has no effect on the speed of c. Has no effect on the speed of

lightlightd. The shorter the wavelength d. The shorter the wavelength

11. The higher the index number11. The higher the index numbera. The higher the speed of lighta. The higher the speed of lightb. The lower the speed of lightb. The lower the speed of lightc. Has no effect on the speed of c. Has no effect on the speed of

lightlightd. The shorter the wavelength d. The shorter the wavelength

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 detectord. The source, the link, and the detector

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 detectord. The source, the link, and the detector

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 dBb. 0.1 dBb. 0.1 dBc. 0.5 dBc. 0.5 dBd. 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 dBb. 0.1 dBb. 0.1 dBc. 0.5 dBc. 0.5 dBd. 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 powerb. Fiber attenuationb. Fiber attenuationc. Connector and splice lossesc. Connector and splice lossesd. 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 powerb. Fiber attenuationb. Fiber attenuationc. Connector and splice lossesc. Connector and splice lossesd. 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 powerd. 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 powerd. 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. 1:10b. 10:1b. 10:1c. 20:1c. 20:1d. 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. 1:10b. 10:1b. 10:1c. 20:1c. 20:1d. 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 measured c. 70 percent of input light should be measured at the outputat 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 measured c. 70 percent of input light should be measured at the outputat 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. 50/125/0.2b. 85/125/0.275b. 85/125/0.275c. 62.5/125/0.275c. 62.5/125/0.275d. 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. 50/125/0.2b. 85/125/0.275b. 85/125/0.275c. 62.5/125/0.275c. 62.5/125/0.275d. 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

Kennedy Questions (Aaron Agoot)

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