ada_est

MULTIPLE CHOICE QUESTIONS IN:

Test yourself- Exam 1-10Noise Chapter 4

Antennas Chapter 6Satellite Communications Chapter 10

Optical Fiber CommunicationsBroadcasting

Microwave CommunicationsAcoustics

Radiation and wave propagationTransmission Fundamentals

Wire and Wireless Communications – Chapter 7Modulation – Chapter 3

Encoded By:

Garcia, Frederick P.Cagaoan, NeilMendoza, DarrenPuro, Genara Mhariz P.Tan, Virson V.Visaya, Luz Regine B.

Test Yourself –Exam 01

1. ECE Board Exam March 1996That dielectric material of an optical fiber surrounding the coreA. CladdingB. ArmorC. Shield D. Cover

2. ECE Board Exam March 1996An antenna that is circularly polarized is the ____________.A. parabolic reflector B. helicalC. Yagi-udaD. small circular loop

3. ECE Board Exam March 1996A word in telegraphy consist of __________ characters plus a word space.A. 11B. 7 and ½C. 8D. 5

4. ECE Board Exam March 1996The number of voice band channels in master group per CCITT standard is __________.A. 300B. 480C. 600D. 120

5. ECE Board Exam March 1996The power of standard test tone is normally ____________.A. 1 dB B. 0 mWC. 1 mWD. 1 W

6. ECE Board Exam March 1996LORAN is a navigational system used primarily for _____________.A. blind landingB. obtaining your fixes location over large distances C. automatic collision warningD. approach control

7. ECE Board Exam March 1996

The expander in a companding device provides ___________.A. greater amplification for low signal levelsB. less amplification for low signal levelsC. greater amplification for high signal levels D. lesser pressure for transmission cables

8. ECE Board Exam March 1996LORAN is a navigation system used primarily for A. approach controlB. obtaining fixes over large distances C. blind landingD. automatic collision warning

9. ECE Board Exam March 1996At what power level does a 1 kHz tone cause zero interference (144 weighted)?A. -90 dBB. -90 dBmC. 90 dBmD. 90 dB

10. ECE Board Exam March 1996One character or a sequence of characters forming a part, or the whole of a message with a specific meaningA. SignsB. Call signC. CodeD. Identifier

11. ECE Board Exam March 1996The K-factor under normal atmospheric conditions in a microwave radio data profile calculation is equal to ___________.A. 2/3B. 0C. 4/3D. Infinity

12. ECE Board Exam March 1996What is the IBM’s asynchronous data link protocol designation?A. 83 BB. 8A1 / 8B1C. 93 BD. 9A1/ 9B1

13. ECE Board Exam March 1996EIRP stands for _______________.A. effective isotropic refracted powerB. effective and ideal radiated power

C. effective isotropic reflected powerD. effective isotropic radiated power

14. ECE Board Exam March 1996The modulation system used for telegraphy isA. frequency-shift keyingB. two-tone modulation C. pulse-code modulationD. single-tone modulation

15. ECE Board Exam March 1996The standard that specifies a balanced interface cable that will operate bit rates up to 10 Mbps with in a span distances up to 1200 m.A. RS-423AB. RS-422AC. RS-550AD. RS-449A

16. ECE Board Exam March 1996An antenna which is not resonant at a particular frequencies and so can be used over a wide band of frequencies and so can be used over a wide band of frequencies is calledA. aperiodicB. boresightC. cassegrainD. top-loaded

17. ECE Board Exam March 1996A receiver connected to an antenna whose resistance is 50 ohms has an equivalent noise resistance of 30 ohms. What is the receiver’s noise temperature?A. 754 KB. 464 KC. 174 KD. 293 K

18. ECE Board Exam March 1996___________ occurs when the microwave beam is at point of grazing over an obstacle.A. DiffractionB. RefractionC. AbsorptionD. Reflection

19. ECE Board Exam March 1996Atmospheric condition is controlled byA. humidityB. pressureC. temperatureD. all of these

20. ECE Board Exam March 1996The characteristics impedance of a transmission line does not depend upon its ________.A. conductor spacingB. conductor diameterC. lengthD. conductor radius

21. ECE Board Exam March 1996What is the purpose of a beat frequency oscillator (BFO)?A. Aid in the reception of weak voice-modulated signalsB. Generates a signal, whose frequency is the same as that of the intermediate frequencyC. Generates a 1kHz note for Morse code receptionD. Generates an output, whose frequency differs from that of the intermediate frequency

by 1 kHz22. ECE Board Exam March 1996

The point on the satellite orbit, closest to the earth isA. progradeB. perigeeC. zenithD. apogee

23. ECE Board Exam March 1996The potential difference between any exposed structured to ground in any electrical installation should not exceed _________ volts RMS.A. 10B. 45C. 0D. 30

24. ECE Board Exam March 1996The capture area of an antenna is directly proportional to the A. frequency of the received signalB. distance between transmitter and receiverC. gain of the antennaD. power density of the signal

25. ECE Board Exam March 1996Modems are required to connect computer to telephone lines because ___________.A. telephone company rules required themB. the telephone network bandwidth is too highC. none of the aboveD. the telephone network will pass direct current

26. ECE Board Exam March 1996The standard reference antenna for the directive gain is ___________.A. elementary doublet

B. isotropic antennaC. half-wave dipoleD. infinitesimal dipole

27. ECE Board Exam March 1996One hundred twenty µbars of pressure variation is equal toA. 120 dBSPLB. 115.56 dBSPLC. 41.58 dBSPLD. 57.78 dBSPL

28. ECE Board Exam March 1996It is a spacecraft placed in orbit around the earth carrying onboard microwave receiver and transmitting equipments.A. Fiber optic equipmentB. Communications satelliteC. Wireless radio systemD. Coaxial cable system

29. ECE Board Exam March 1996One type of pulse communications system uses pulse that appear as a group, and which vary in number according to the loudness of the voice. This type of pulse modulation is calledA. pulse duration modulationB. pulse amplitude modulationC. pulse code modulationD. pulse position modulation

30. ECE Board Exam March 1996A device to be connected across the headset in telephone receivers to reduce the effects of acoustic shock.A. GroundB. Two rectifiers in parallel with opposite polaritiesC. ProtectorD. Fuse

31. ECE Board Exam March 1996Judgment on the case against an ECE shall become final and executory after A. 10 daysB. 60 daysC. 30 daysD. 15 days

32. ECE Board Exam March 1996The equivalent noise temperature of the amplifier is 25 K. What is the noise figure?A. 1.86B. 0.1086

C. 1.086D. 10.86

33. ECE Board Exam March 1996The letter-number designation B8E is a form of modulation also known as ___________.A. pilot carrier systemB. independent sideband emissionC. lincomplexD. vestigial sideband transmission

34. ECE Board Exam March 1996When the transmitting and receiving antennas are in line-of-sight of each other, the mode of propagation is ________ wave.A. space or directB. groundC. surfaceD. sky

35. ECE Board Exam March 1996Crosstalk coupling is ___________.A. dBm (disturbing pair) minus dBm (disturbed pair)B. the difference between readings on a cable pair with a tone and a cable pair without

tone read at the far end of a cableC. signals from one circuit that get into another circuitD. All of these are true

36. ECE Board Exam March 1996According to the Nyquist theorem, the sampling rate that can be used in a PCM system is ________ the highest audio frequency.A. onceB. eight timesC. twiceD. thrice

37. ECE Board Exam March 1996Passive crossover components cause some frequencies to be delayed with respect to the other frequencies at the crossover point.A. Phase shiftB. Phase correctionC. Phase-error correctionD. Time alignment

38. ECE Board Exam March 1996A car horn outdoors produces a sound intensity level of 90 dB at 10 ft away. At this distance, what is the sound power in watt?A. 12 WB. 0.12 W

C. 0.012 WD. 1.2 W

39. ECE Board Exam March 1996What is the one principal difference between synchronous and asynchronous transmission?A. the pulse height are different B. the clocking is derived from the data in synchronous transmissionC. the clocking is mixed with the data in asynchronousD. the bandwidth required is different

40. ECE Board Exam March 1996The lowest layer in the ionosphereA. DB. F2C. ED. F1

41. ECE Board Exam March 1996What is the number of pins in the RS-232C interface?A. 25B. 15C. 20D. 20

42. ECE Board Exam March 1996SSB transmission requires only ______ of the bandwidth for a DSBFC transmission.A. ¼B. 2/3C. ½D. ¾

43. ECE Board Exam March 1996The method of generating FM used by broadcasting station isA. direct B. all of theseC. indirectD. insertion

44. ECE Board Exam March 1996What is the transmission rate of a system for transmitting the output of a microcomputer to a line printer operating at a speed of 30 lines/minute? Assume that the line printer has 8 bits of data per character and prints out 80 characters/line.A. 800 bpsB. 400 bpsC. 320 bpsD. 640 bps

45. ECE Board Exam March 1996Communications code is ____________.A. eight bits per characterB. agreed upon in advance between sender and receiverC. the same in all modern computersD. either seven or eight bits per character

46. ECE Board Exam March 1996What is the reference tone level for dBm?A. -82 dBmB. -85 dBmC. -67 dBmD. -90 dBm

47. ECE Board Exam March 1996A type of an underground antenna is a/an __________ antenna.A. HertzB. isotropicC. parabolicD. Marconi

48. ECE Board Exam March 1996Which of the following pulse modulation systems is analog?A. DeltaB. Differential PCMC. PWMD. PCM

49. ECE Board Exam March 1996What is the purpose of the receiver’s squelch circuit?A. To overcome fluctuations in the level the RF signal arriving at the receiver antennaB. To prevent fluctuations in the AGC bias levelC. To reduce the receiver’s sensitivity to all incoming signalsD. To prevent amplified noise from reaching the loudspeaker during the absence of an

incoming signal50. ECE Board Exam March 1996

TACAN is a navigational aid providing ___________.A. bearing and distance indicationB. speed and height indicationC. bearing and weather informationD. instrument-landing glide paths

51. ECE Board Exam March 1996In __________ transmission, a unique SYNC character is transmitted at the beginning of each message.A. asynchronous

B. synchronousC. digital D. analogue

52. ECE Board Exam March 1996If the terminating impedance is exactly equal to the characteristic impedance of the transmission line the return loss is ___________.A. zeroB. oneC. infiniteD. None of these

53. ECE Board Exam March 1996What is the main purpose of a communications system?A. None of theseB. To have a frequency assignmentC. For modulationD. To provide an acceptable replica of the information at the destination

54. ECE Board Exam March 1996What is meant by antenna gain?A. The final amplifier gain minus the transmission line losses (including any phasing

lines present)B. The ratio of the amount of power produced by the antenna compared to the output

power of the transmitterC. The ratio of the signal in the backward directionD. The numeric ratio relating the radiated signal strength of an antenna to that of another

antenna55. ECE Board Exam March 1996

Binary communications systems are better becauseA. they can interface directly with the analog telephone networkB. the components are simpler, less costly, and more reliableC. people think better in binary D. interstate calls are less costly

56. ECE Board Exam March 1996In the phase shift method, how many circuits must be balanced?A. None of theseB. 1C. 4D. 2

57. ECE Board Exam March 1996The carrier swing necessary to provide 80% modulation in the FM broadcasting band is __________.

A. 150 kHzB. 120 kHzC. 60 kHzD. 75 kHz

58. ECE Board Exam March 1996The correctness and accuracy of the transmitted message content isA. verified by the modemB. communications systemC. determined by the sender and receiverD. ensured by use of digital technique

59. ECE Board Exam March 1996The signal in a channel is measured to be 23 dB while noise in the same channel is measured to be 9 dB. The signal to noise ratio therefore is __________.A. 9/23B. 23/9C. 32 dBD. 14 dB

60. ECE Board Exam March 1996Three audio waves with 100,200 and 300 volts amplitude respectively, simultaneously modulate a 450 volts carrier. What is the total percent of modulation of the AM wave?A. 69 %B. 115.5 % C. 50%D. 83%

61. ECE Board Exam March 1996If the percentage modulation of an AM amplifier is 88% and the modulating signal is 1 volt, the carrier has an amplitude of _______________.A. 1.14 voltsB. 0.88 voltC. 1.88 voltsD. 0.12 volt

62. ECE Board Exam March 1996It consists of a number of dipoles of equal size, equally spaced along a straight line with all dipoles fed in the same phase from the same source.A. Log-periodic antennaB. Yagi antennaC. End-fire arrayD. Broadside array

63. ECE Board Exam March 1996Data switching systems.A. improve the efficiency of data transfer

B. are limited to small data networksC. required additional linesD. are not used in data system

64. ECE Board Exam March 1996A type of array antenna which consists of one half-wave driven dipole, one reflector and one directorA. Hertzian dipoleB. Yagi-udaC. Broadside collinearD. Log periodic dipole array

65. ECE Board Exam March 1996Power is a/an _____________ amount of energy used in specific period of timeA. largeB. definiteC. electricalD. relative

66. ECE Board Exam March 1996The midrange frequency range of sound is fromA. 256 to 2048 HzB. 2048 to 4096 HzC. 512 to 2048 HzD. 16 to 64 Hz

67. ECE Board Exam March 1996To connect coaxial line to a parallel-wire _________ is the best to use.A. directional couplerB. quarter-wave transformerC. balunD. slotted line

68. ECE Board Exam March 1996In AM, the carrier carries ____________ intelligence.A. noB. differenceC. distortedD. same

69. ECE Board Exam March 1996Characteristics impedance of a transmission line is the impedance measured at the ___________ when its length is infinite.A. inputB. shorted end of the lineC. outputD. midsection

70. ECE Board Exam March 1996Cross modulation on a receiver is eliminated at theA. RF stageB. mixer stageC. IF stageD. detector stage

71. ECE Board Exam March 1996A speaker cabinet has an internal volume 84,950 cm3. It has a port area on the baffle of 3,230 cm2 and baffle thickness of 19 mm. What is the Helmholtz resonance hertz of this speaker enclosure?A. 260 HzB. 245 HzC. 265 HzD. 250 Hz

72. ECE Board Exam March 1996What quarterwave transformer will match a 100Ω line to an antenna whose value is 175Ω?A. 132.29 ΩB. 150 Ω C. 16.58 ΩD. 137.5 Ω

73. ECE Board Exam March 1996The local loop of the telephone system is understood to beA. a single piece of wire connecting the subscriber’s telephone set to another telephone

set in an adjacent roomB. a two-wire or four-wire communication circuit between the customer’s premise and

central officeC. a four-wire circuit connecting a facsimile machine to a computer D. a group of wires connecting a telephone set to a modem

74. ECE Board Exam March 1996In what region of the world is sporadic-E most prevalent?A. The equatorial regionsB. The northern hemisphereC. The arctic regionsD. The polar regions

75. ECE Board Exam March 1996The process of assigning PCM codes to absolute magnitudesA. OverloadingB. All of theseC. QuantizingD. Multiplexing

76. ECE Board Exam March 1996It is a measure of the microwave power radiated from an antenna as a function of angular direction from the antenna axis.A. Antenna patternB. PolarizationC. BeamwidthD. Sidelobes

77. ECE Board Exam March 1996It is the made from semiconductor material such as aluminum-gallium-arsenide or gallium-arsenide-phosphide.A. APDB. Injection laser diodeC. Light emitting diodeD. Positive-intrinsic-negative

78. ECE Board Exam March 1996Which one is not the basic electrical protection measures in the Philippine Electronics Code?A. Voltage/ current limiting and interruptingB. UndergroundingC. Grounding and bondingD. Shielding

79. ECE Board Exam March 1996What does the noise weighting curve shows?A. Noise signals measured with a 144 handsetB. Power levels of noise found in carrier systemsC. The interfering effect of other frequencies in a voice channel compared with a

reference frequency of one kilohertzD. Interfering effects of signals compared with a 3-kHz tone

80. ECE Board Exam March 1996What is the difference between phase and frequency modulation?A. Is purely theoretical because they are the same in practiceB. Lies in poorer audio response of phase modulationC. Lies in the different definitions of the modulation indexD. Is too great to make two systems compatible

81. ECE Board Exam March 1996When a transmission line uses ground return, it is called a/an __________ line.A. ungroundedB. balancedC. unbalancedD. grounded

82. ECE Board Exam March 1996

What is the gain of four identically polarized antennas stacked one above the other and fed in phase?A. 3 dB over the gain of one antennaB. 10 dB over the gain of one antennaC. 4 dB over the gain of one antennaD. 6 dB over the gain of one antenna

83. ECE Board Exam March 1996The ratio of the level of the modulated output of a transmitter under conditions of standard test modulation to the level of the demodulated output with no modulation applied both measured with the same bandwidth.A. Reference audio outputB. None of theseC. Audio frequency responseD. Residual noise level

84. ECE Board Exam March 1996The ___________ filter attenuates signals but passes frequencies below and above that band.A. low passB. band passC. band stopD. high pass

85. ECE Board Exam March 1996In a telephone system, the customer’s telephone directory numbering is from 000 to 999, what is the capacity of the system?A. 1000 linesB. 100,000 linesC. 10,000 linesD. 100 lines

86. ECE Board Exam March 1996An absorption loss caused by valence electrons in the silica material from which fibers are manufactured.A. Modal dispersionB. Infrared absorptionC. Ion resonance absorptionD. Ultraviolet absorption

87. ECE Board Exam March 1996In an FM receiver, which circuit removes amplitude variations? A. ExciterB. MixerC. DiscriminatorD. Limiter

88. ECE Board Exam March 1996A one-hop, full duplex, microwave system in a space diversity arrangement. Determine “how many receivers in all are used?”A. 8B. 2C. 4D. 6

89. ECE Board Exam March 1996The frequency spectrum of the stereophonic FM signal.A. 67 kHzB. 59.5 to 74.5 kHzC. 19 to 38 kHzD. 30 to 53 kHz

90. ECE Board Exam March 1996Termination meansA. result of disconnecting a line from a transmitterB. result of cutting both ends of a conductorC. looking back impedance of a line with no loadD. load connected to the output end of a transmission line

91. ECE Board Exam March 1996Asynchronous protocol isA. message oriented B. clock orientedC. bit orientedD. character oriented

92. ECE Board Exam March 1996Transmission lines are either balanced or unbalanced with respect to _________.A. negative terminalB. inputC. groundD. positive terminal

93. ECE Board Exam March 1996What is the velocity factor for non-foam dielectric 50 or 75 ohm flexible coaxial cable such as RG 8, 11, 58 and 59?A. 2.70B. 0.10C. 0.66D. 0.30

94. ECE Board Exam March 1996Gain of an isotropic antennaA. -1 dB

B. 1 dBC. 0 dBD. 2 dB

95. ECE Board Exam March 1996In measuring noise in a voice channel at a 4 dB test point level, the meter reads -70 dBm (F1A weighted), convert the reading to pWp.A. 53B. 93C. 63D. 83

96. ECE Board Exam March 1996Power is always __________.A. a definite amount of energyB. all of theseC. the rate at which energy is used D. expressed in watts

97. ECE Board Exam March 1996Radio fading resulting from obstruction losses.A. Log normal fadingB. None of theseC. Multi-path fadingD. Rayleigh fading

98. ECE Board Exam March 1996After the IF stages have been aligned, the next stage to align in FM receiver is.A. local oscillatorB. limiter stageC. RF amplifierD. mixer stage

99. ECE Board Exam March 1996___________ is a device in data transmission to interface data terminal equipment to an analogue transmission line.A. RS 232B. ConnectorC. ModemD. RJ-11 plug

100.ECE Board Exam March 1996What is the primary advantage of DSBSC in AM?A. Reduce bandwidth over standard AMB. All of theseC. It is simpler to transmit and receive than the standard AMD. No transmitter power is wasted in the carrier

Test Yourself – Exam 02

1. ECE Board Exam November 1996Which frequency band is the standard AM radio broadcast?A. HFB. UHFC. MFD. VHF

2. ECE Board Exam November 1996A system that performs parallel-to-serial and serial-to-parallel conversion of data link.A. DCEB. DTEC. ModemD. PC

3. ECE Board Exam November 1996

The line control unit (LCU) operates on the data digital form.A. Data communications equipment (DCE)B. UART C. Modem D. Data terminal equipment (DTE)

4. ECE Board Exam November 1996Quantization noise is caused byA. binary coding techniquesB. serial transmission errorsC. the synchronization between encoder and decoderD. the approximation of the quantized signal

5. ECE Board Exam November 1996Speaker is a device that __________.A. convert current variations into sound wavesB. none of theseC. convert electrical energy to mechanical energyD. convert sound waves into current and voltage

6. ECE Board Exam November 1996An object farther from a converging lens than its focal point always has a/an _______ image.A. virtualB. the same in sizeC. invertedD. smaller size

7. ECE Board Exam November 1996The loss in signal power as light travels down a fiber isA. attenuationB. propagationC. absorptionD. scattering

8. ECE Board Exam November 1996Energy that has neither been radiated into space nor completely transmitted.A. Captured wavesB. Incident wavesC. Standing wavesD. Modulated waves

9. ECE Board Exam November 1996One of the reasons why FDM is being replaced by TDM isA. noise is amplified with voice when an FDM system is usedB. it is difficult to place channels side by sideC. there is more time than frequency

D. Most available frequencies has been used10. ECE Board Exam November 1996

Which determines the number of sideband components of FM?A. Modulation frequencyB. Modulation indexC. Carrier frequencyD. All of these

11. ECE Board Exam November 1996How would one squeeze more channels of communication into TDM frames of standard length?A. Shorten the time delay for each channelB. Raise the amplitudeC. Add modulatorsD. Remove the synchronizing pulses

12. ECE Board Exam November 1996When one stations is designated as master and rest of the stations are considered slaves message handling is ________.A. pollingB. WANC. LAND. OSI

13. ECE Board Exam November 1996How many satellite orbital slots are requested by the Philippine government from ITU?A. 2B. 6C. 5D. 3

14. ECE Board Exam November 1996The output of a balanced modulator is ____________.A. LSB and USBB. LSBC. USBD. Carrier

15. ECE Board Exam November 1996RS-232, RS-449, RS-530, V, 24 and X.21 are examples of ____________.A. standards for interfaces between modems and transmission facilities B. standards for various types of transmission channelsC. standards for interfaces between terminals and modemsD. standards for end to end performance of data communications system

16. ECE Board Exam November 1996A special service circuit connecting two private branch exchanges (PBX).

A. Phantom lineB. Private lineC. Tie trunkD. Tandem trunk

17. ECE Board Exam November 1996What is the baseband frequency of standard FDM basic supergroup?A. 312 to 552 kHzB. 300 to 600 kHzC. 60 to 2540 kHzD. 60 to 108 kHz

18. ECE Board Exam November 1996What is the data rate of the ISDN Basic access B channel?A. 192 kbpsB. 32 kbpsC. 64 kbpsD. 144 kbps

19. ECE Board Exam November 1996Which tester is used to measure SWR?A. Spectrum analyzerB. MultimeterC. ReflectometerD. Oscilloscope

20. ECE Board Exam November 1996What is the transmission rate of a GSM cellular system?A. 64 kbpsB. 240 kbpsC. 128 kbpsD. 270 kbps

21. ECE Board Exam November 1996A dipole antenna requires to be feed with 20 kW of power to produce a given signal strength to a particular distant point. If the addition of a reflector makes the same field strength available with an input power of 11 kW. What is the gain in dB obtain by the use of the reflector? (Gain referred to this particular dipole)A. 4.24B. 1.81C. 4.75D. 2.6

22. ECE Board Exam November 1996Pulse carrier at the ratio of 8000 pulse/sec is amplitude modulated by an analog signal this type of modulation isA. PAM

B. ADM C. DMD. PCM

23. ECE Board Exam November 1996What is the applied power if a thermal RF wattmeter is connected to a transmitter through a variable attenuator? The wattmeter reads 84 mW when 15 dB of attenuation is used.A. 4.656 wattsB. 2.656 wattsC. 3.656 wattsD. 2.856 watts

24. ECE Board Exam November 1996Collects very weak signal from a broadcast satelliteA. Satellite dishB. LNBC. Yagi-Uda antennaD. Satellite receiver

25. ECE Board Exam November 1996A seven-bit character can represent one of _________ possibilities.A. 14B. 64C. 128D. 7

26. ECE Board Exam November 1996The maximum power suggested by KBP on 919-1312 AM broadcast station in Metro Manila isA. 10 kWB. 20 kWC. 15 kWD. 5 kW

27. ECE Board Exam November 1996A loudspeaker cabinet has an internal volume of 5,184 in3 (84,950 cm3). It has a port area on the baffle of 50 in2 (322.58cm2) and a thickness of 0.70 in (18 mm). What is the Helmholtz resonance, in hertz, of this loudspeaker enclosure?A. 250 HzB. 245 HzC. 240 HzD. 255 Hz

28. ECE Board Exam November 1996When the clearance above the obstruction is equal to the radii of even Fresnel zone at the point of reflection the RSLA. remains the same

B. is above threshold C. is decreasedD. is increased

29. ECE Board Exam November 1996Digital transmission provides a higher level of signal quality than analog transmission becauseA. repeaters regenerate digital pulses and remove distortionB. digital signals are easier to sample than analog signalsC. digital signals are smaller than analog signals and cannot easily be distortedD. analog signals are continuous and not easily distorted.

30. ECE Board Exam November 1996A _________ interconnects LAN having identical protocols at the physical and data link layers.A. All of theseB. bridgeC. routerD. Gateway

31. ECE Board Exam November 1996Both frequency and phase modulation utilize ________ modulationA. PhaseB. AM and FMC. DigitalD. Angle

32. ECE Board Exam November 1996The different angles of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitter is known as ________.A. refraction B. sensorC. modeD. emitter

33. ECE Board Exam November 1996An invitation from the primary to a secondary to transmit a message.A. Retransmission B. SelectionC. ReuseD. Polling

34. ECE Board Exam November 1996An agency of the United Nations that formulates standards and recommend practices for all civil aviationA. ICAOB. CAA

C. IATAD. ATO

35. ECE Board Exam November 1996The transformer signal coding method for T1 carrier is A. BinaryB. NRZC. ManchesterD. Bipolar

36. ECE Board Exam November 1996When the value of k increases, the effective result is ______ of the equivalent curvatures.A. downward curvaturesB. flatteningC. bulgingD. sharp curvature

37. ECE Board Exam November 1996An electromagnetic wave consists of A. a magnetic field onlyB. both electric and magnetic fieldsC. an electric field onlyD. non-magnetic field only

38. ECE Board Exam November 1996In a transmission line, if the maximum current to minimum current ratio is 2:1 what is the ratio of the maximum voltage to minimum voltage?A. 4:1B. 1:2 C. 1:4 D. 2:1

39. ECE Board Exam November 1996Satellite signal transmitted from a satellite transponder to earth’s station.A. Vertically polarizedB. UplinkC. DownlinkD. RHCP

40. ECE Board Exam November 1996Multiplexing scheme use by baseband transmission.A. FDMB. Space multiplexingC. TDMD. Statistical multiplexing

41. ECE Board Exam November 1996Which stands for dB relative level?

A. dBrnB. dBmC. dBrD. dBa

42. ECE Board Exam November 1996What is the maximum color TV bandwidth?A. 1.6 MHzB. 0.5 MHzC. 1.0 MHzD. 1.3 MHz

43. ECE Board Exam November 1996If Ns=250, determine the earth radius k-factor.A. 1.98B. 1.23C. 1.33D. 1.29

44. ECE Board Exam November 1996Digital modulation technique used in modems.A. ASKB. PSK C. FSKD. All of these

45. ECE Board Exam November 1996Which of the following is not a baseband signal modulation?A. RF carrierB. Video SystemC. Audio signalD. Binary coded pulses

46. ECE Board Exam November 1996The standing wave ratio is equal to ________ if the load is properly matched with the transmission line.A. 1B. 50C. 10D. 2

47. ECE Board Exam November 1996Noise from random acoustic or electric noise that has equal per cycle over a specified total frequency band.A. Thermal noiseB. White noiseC. Gaussian noise

D. All of these48. ECE Board Exam November 1996

When was the UHF channel (14-83) of television were added?A. 1852B. 1904C. 1947D. 1952

49. ECE Board Exam November 1996Multiplexing in a time division multiplexer occurs based uponA. the position of a frame within the group of framesB. the positioning of data within a frame C. the priority assigned to a connected deviceD. the activity of a connected device

50. ECE Board Exam November 1996Ethernet is baseband system using CSMA/CD operating at A. 20 MbpsB. 10 MbpsC. 30 MbpsD. 40 Mbps

51. ECE Board Exam November 1996A microwave communications system space loss calculation formula isA. 92.4 + 10 log f +20 log dB. 94.2 + 10 log f +20 log dC. 92.4 + 20 log f +20 log dD. 94.2 + 20 log f +20 log d

52. ECE Board Exam November 1996Which is the non-resonant antenna?A. Broadside AntennaB. Folded DipoleC. Rhombic antennaD. End fire array

53. ECE Board Exam November 1996The first commercial satelliteA. Explorer B. SputnikC. TelstarD. Early bird

54. ECE Board Exam November 1996A quadrature signaling have ________ possible states.A. 16B. 8

C. 32D. 4

55. ECE Board Exam November 1996Proposed the use of a clad glass fiber as a dielectric waveguide.A. Kao and KeckB. Karpon and KeckC. Karpon and BockhamD. Bockham and Kao

56. ECE Board Exam November 1996What band does VSAT first operate?A. X-band B. C-bandC. Ku-bandD. L-band

57. ECE Board Exam November 1996What is the method of diversity reception where the signal is transmitted on 2 different frequencies over the same path?A. QuadrupleB. FrequencyC. PolarizationD. Space

58. ECE Board Exam November 1996The wavelength of light has no role inA. DiffractionB. InterferenceC. Resolving powerD. Polarization

59. ECE Board Exam November 1996Which of the following filters block FM radio band for TV channels (2 to 13)?A. High-pass filterB. Band reject filterC. Low-pass filterD. Band-pass filter

60. ECE Board Exam November 1996The standard ASCIIA. is version II of ASCB. is used only in US and CanadaC. has 132 characters including 32 control charactersD. is subset of 8-bit EBCDIC code

61. ECE Board Exam November 1996Luminous efficiency is least for a

A. mercury vapor lamp B. low-wattage light bulb C. high-wattage light bulbD. fluorescent tube

62. ECE Board Exam November 1996Transmission lines when connected to antenna have A. capacitive loadB. resistive load whose resistance is less than characteristics impedanceC. resistive load at the resonant frequencyD. resistive load whose resistance is greater than the characteristic impedance of the line

63. ECE Board Exam November 1996What is the free space loss, in dB, between two microwave parabolic antennas 38.0 kilometer apart operating at 7.0 GHz?A. 145.6 dBB. 138.5 dBC. 135.5 dBD. 140.89 dB

64. ECE Board Exam November 1996What is the equivalent output of a circuit in dBm, if it is has an output of 10 watts?A. 10 dBmB. 30 dBmC. 20 dBmD. 40 dBm

65. ECE Board Exam November 1996Satellite engine useA. liquid fuelB. jet propulsionC. ion propulsion systemD. solar jet

66. ECE Board Exam November 1996Low-power radar usesA. RIMPATTB. TRAPATTC. MagnetronD. IMPATT

67. ECE Board Exam November 1996Transmission line must be matched to the load toA. transfer maximum voltage to the loadB. transfer maximum current to the loadC. reduce the load currentD. transfer maximum power to the load

68. ECE Board Exam November 1996Electromagnetic wave travel at __________ in free space.A. 300,000 km/secB. 100,000 km/ secC. 400,000 km/secD. 200km/sec

69. ECE Board Exam November 1996When electromagnetic wave are propagated through a waveguide, theyA. are reflected from the walls but do not travel along themB. travel along all four walls of the waveguideC. travel along the broader walls of the guideD. travel through the dielectric without touching the walls

70. ECE Board Exam November 1996Codes must beA. agreed upon in advance between sender and receiverB. eight bit per characterC. the same in all modern computer D. either seven or eight bits per character

71. ECE Board Exam November 1996Combination of modulator, channel and detector.A. TransceiverB. Discrete channelC. T/R channelD. Transponder

72. ECE Board Exam November 1996What is the stage of the sand becoming silicon?A. HotB. GasC. LiquidD. Molten

73. ECE Board Exam November 1996Noise reduction system used for film sound in movieA. dBxB. dolbyC. dBaD. dBm

74. ECE Board Exam November 1996What is the principal difference between asynchronous and synchronous transmission?A. The clocking is mixed with the data in synchronous transmissionB. The pulse height are difficultC. The clocking is derived from the data in synchronous

D. The bandwidth required is difficult.75. ECE Board Exam November 1996

You are measuring a voice channel at a -4 dB test point level, the meter reads -73 dBm (pure test tone) convert the reading in dBmCO.A. 16B. 18C. 22D. 12

76. ECE Board Exam November 1996What is the type of emission use by standard AM radio broadcast?A. A0B. F3C. A3D. A5C

77. ECE Board Exam November 1996____________ is the average rate of transmission of sound energy in a given direction through a cross sectional area of 1 sq.m. at right angle to the direction.A. Sound pressureB. Sound intensityC. Pressure variationD. Loudness

78. ECE Board Exam November 1996Top loading is used in an antenna in order to increase its ___________.A. input capacitance B. beamwidthC. bandwidth D. effective height

79. ECE Board Exam November 1996What component in the telephone set has the primary function of interfacing the handset to the local loop?A. VaristorB. Induction coilC. ResistorD. Capacitor

80. ECE Board Exam November 1996The first passive satellite transponder.A. Early birdB. ScoreC. MoonD. Sputnik

81. ECE Board Exam November 1996

The primary purpose of the data modem is to A. interface analog terminal equipment to analog communications channelB. interface digital terminal equipment to analog communications channelC. interface analog terminal equipment to digital communications channelD. interface digital terminal equipment to digital communications channel

82. ECE Board Exam November 1996____________ is the out-of-band signaling between toll central offices (Bell System Standard)A. 2,000 HzB. 800 HzC. 3,835 HzD. 3700 Hz

83. ECE Board Exam November 1996Which symbol indicates that only one sideband is transmitted?A. A3EB. B8EC. C3FD. H3E

84. ECE Board Exam November 1996A voice-grade circuit using the PTN has an ideal passband ofA. 0 to 4 HzB. 0 to 4 kHzC. 0 to 4 GHzD. 0 to 4 MHz

85. ECE Board Exam November 19961 micron is equal to ___________ meter(s).A. 10-6mB. 10-3 mC. 106 mD. 109 m

86. ECE Board Exam November 1996The lowest resistance grounding on earth A. SandB. ClayC. Surface loam soilD. Limestone

87. ECE Board Exam November 1996Troposheric scatter uses the frequencies in the ________ band.A. VLFB. UHFC. VHF

D. UF88. ECE Board Exam November 1996

The unit of pitchA. DecibelB. PhonC. MelD. Sone

89. ECE Board Exam November 1996What kind of receiver is used in conventional telephone handset?A. CapacitorB. CarbonC. ElectromagneticD. Ceramic

90. ECE Board Exam November 1996Basic speed rate of digital system.A. 144 kbpsB. 1,544 kbpsC. 64 kbpsD. 2,048 kbps

91. ECE Board Exam November 1996A horizontal antenna isA. centrally polarizedB. vertically polarizedC. horizontally polarizedD. perpendicularly polarized

92. ECE Board Exam November 1996What is the diameter of a copper wire to be used in a 16 km loop with a dc loop resistance of 100 ohms/km?A. 0.108 cmB. 1.082 cmC. 0.017 cmD. 0.0465 cm

93. ECE Board Exam November 1996If a fiber optic system has a rise time of 16 ns, the source rise time is 1.5 ns and the detector rise time is 2 ns, what is the cable rise time?A. 14 nsB. 6 nsC. 9 nsD. 12.5 ns

94. ECE Board Exam November 1996What is the phase delay of an 800 Hz voice signal if the phase shift is 15 degrees?

A. 1.25 µsec B. 52 µsec C. 83.33 µsec D. 26 µsec

95. ECE Board Exam November 1996What is the power loss of a telephone hybrid?A. 6 dBB. 2 dBC. 3 dBD. 1 dB

96. ECE Board Exam November 1996You are measuring noise in a voice channel at 7 dB test point level. The meter reads -56 dBm (FIA weighted). What is the reading in dBrnc?A. 20B. 32 C. 35 D. 25

97. ECE Board Exam November 1996Space diversity transmission means transmitting and receiving onA. two or more antennas operating on two different frequenciesB. two or more identical frequenciesC. two or more different frequenciesD. two or more antennas operating on the same frequencies

98. ECE Board Exam November 1996Rules governing the transmission of digital information.A. Line protocolB. IsochronousC. Data communicationsD. Digital communications

99. ECE Board Exam November 1996A digital identification associated with a cellular systemA. SAT B. ESN C. MIN D. SIM

100.ECE Board Exam November 1996____________ is measuring the propagated field strength over the projected service areaA. Radio soundingB. None of theseC. Radio monitoringD. Radio survey


1. ECE Board Exam April 1997

What is the impedance of a balance 4-wire with a diameter of 0.25 cm and spaced 2.5 cm apart using an insulator with a dielectric constant of 2.56?

A. 100ΩB. 65ΩC. 75 ΩD. 50 Ω


What is the impedance in ohms of a transformer marked for 25V, 4W, when the secondary is correctly loaded?

A. 150 ΩB. 156 ΩC. 160 ΩD. 165 Ω


A single conductor running from the transmitter to the antenna.

A. RG-8/UB. Single line wireC. Twin-leadD. MIcrostrip


If voltage change equal to twice its original value, what is its corresponding change in dB?

A. 9 dBB. 6dBC. 10 dBD. 3dB


To couple a coaxial line to parallel line, it is better to use a ______.

A. Slotted lineB. Quarter-wave transformerC. Directional CouplerD. Balun


What is the characteristic impedance of a single wire with a diameter d= 0.25 mm placed at the center between grounded parallel planes separated by 1 mm apart. The wire is held by a material with a velocity factor of 0.75.

A. 85 ΩB. 63 ΩC. 50 ΩD. 75 Ω


If you have available number of power amplifiers with a gain of 100 each, how many such amplifiers do you need to cascade to give an overall gain of 60 dB?

A. 3B. 4C. 5D. 2


________ sets a limit on the maximum capacity of a channel with a give noise level.

A. Hartley theoremB. Shannon-Hartley theorem

C. Nyquist theoremD. Shannon theorem


Transmission sent in both directions simultaneously.

A. Full duplexB. DuplexC. Half duplexD. Simplex


Industrial noise frequency is between _________.

A. 200 to 3000 MhzB. 15 to 160 MhzC. 0 to 10 KhzD. 20 Ghz


Reference noise temperature.

A. 70 deg FB. 30 deg CC. 290 KelvinD. 25 deg C


What is the reference frequency of CCITT psophometric noise measurement?

A. 800 HzB. 1500 HzC. 3400 HzD. 1000 Hz


Which does not effect noise in a channel?

A. None of theseB. Bandwidth C. TemperatureD. Quantizing level


The random and unpredictable electric signal from natural causes, both internal and external to the system is know as ________.

A. DistortionB. NoiseC. AttenuationD. Interference


The most common unit of noise measurement in white noise testing.

A. dBwB. dBkC. dBmD. NPR


Unit of noise power of psophometer

A. dBaB. pWpC. dBmD. dBmO


100% modulation in AM means a corresponding increase in total power by:

A. 25%B. 75%C. 100%D. 50%


If the modulation index of an AM wave is doubled, the antenna current is also doubled, the AM system being used is

A. A5CB. A3JC. A3HD. A3


What particular circuit that rids FM of noise?

A. HPFB. Phase shifterC. LimiterD. LPF


What is the advantage of PTM over PAM?

A. All of theseB. Low sampling rate is requiredC. Much better noise immunityD. Simpler to generate


At 100% modulation, the sum fo the effective voltages in both sidebands is equal to ______% of the unmodulated carrier voltage.

A. 50B. 71C. 100D. 25


A carrier signal has ______.

A. Constant peak amplitude

B. The informationC. Frequency range 20-20000 HzD. A varying amplitude


Which transmit only one sideband?

A. A3EB. 3AJC. 11BED. H3E


The final amplifier of either FM or AM transmitter operates as

A. Class BB. Class CC. Class AD. Class D


Modulation means

A. Varying of informationB. Utilization of a single transmission channel to carry multiple signalsC. Varying of some parameters of a carrier such as its amplitude to transmit informationD. Transmit pulses in DC form on a copper wire


What is the advantage of sidetone?

A. High transmission efficiencyB. Results to a strengthened signalC. No energy dissipationD. Assures that the telephone is working


The standard test tone

A. 0dBB. 10 dBmC. 0 dBmD. 10 dB


One (1) Erlang is equal to ________.

A. 360 CCSB. 100 CCSC. 36 CCSD. 3.6 CCS


Transmission of printed material over telephone lines.

A. Video textB. FacsimileC. EncodingD. Xerox copy


1-CCS is equal to?

A. 60B. 100C. 600D. 1


1 Erlang is ______.

A. 1000 TUB. 10 TUC. 100TUD. 1 TU


When waves bend away from straight lines of travel, it is called _________.

A. RefractionB. ReflectionC. RarefactionD. Diffraction


Highest frequency that can be used for skywave HF communications between two given points on earth.

A. Gyro frequencyB. Maximum usable frequencyC. Critical frequencyD. Virtual frequency


Electromagnetic radiation theory was profounded by ______.

A. Sir Edward AppletonB. Sir Isaac NewtonC. James Clerk MaxwellD. Michael Faraday


Type of transmission path that permits communication in the frequency range from 30 to 60 MHz and over distances form about 1000 to 2000 km.

A. DuctingB. Ionospheric scatterC. MicrowaveD. Troposcatter


What is the thickest layer of the ionosphere?

A. EB. F1C. F2D. D


Distance traveled by a wave in the time of one cycle.

A. HopB. FrequencyC. WavelengthD. Crest


Which region of the ionosphere is mainly responsible for long distance night time communication?

A. A layerB. D layerC. E layer D. F layer


What is the effective earth’s radius when N=300?

A. 8500 kmB. 6370 kmC. 7270 kmD. 7950 km


The polarization of a discone antenna is _____.

A. HorizontalB. VerticalC. OmniD. Directional


_______ is the horizontal pointing angle of an antenna.

A. Right angleB. Angle of elevationC. BandwidthD. Azimuth


Which is properly terminated antenna?

A. RhombicB. HertzC. MarconiD. Dipole


______ is a device that detects both vertically and horizontally polarized signals simultaneously.

A. CrystalB. Orthomode transducerC. Light transducerD. Optoisolator


How much does the radiated power of an antenna increases if its current increased by 3.3 times?

A. 6.6 timesB. 3.3 timesC. 10.89 timesD. 9.9 times


What do you call the energy that was not radiated into space or completely transmitted?

A. Incident waves

B. Captured wavesC. Standing wavesD. Modulated waves


What is the estimated medium wind loading in the Philippines for antenna tower design?

A. 200 kphB. 250 kphC. 300 kphD. 100 kph


The minimum number of turns a helix antenna must have.

A. 4B. 5C. 3D. 6


When testing transmitter to prevent interfering with other stations, which type of antenna must be used?

A. Dummy antennaB. Hertzian antennaC. None of theseD. Void antenna


A device that radiates electromagnetic energy and or intercepts electromagnetic radation.

A. AntennaB. TransmitterC. Transmission lineD. Transceiver


The frequency of operation of a dipole antenna cut to length of 3.4 m.

A. 42.9 MHzB. 61.3 MHzC. 38.5 MHzD. 53.5 MHz


Full duplex transmission means

A. One way transmissionB. 24-hour transmissionC. Broadcast transmissionD. Two-way simultaneous transmission


Transmission system for a multidrop network

A. Taken passingB. PollingC. SwitchingD. CSMA/CD


Synchronous modems cost more than asynchronous modem because _______.

A. They have larger bandwidthB. They are largerC. The production volume is largerD. They have clock recovery circuits


What equation defines the composition of an ISDN basic access line?

A. B+2DB. B+DC. 2B+2D

D. 2B+D


Modem is referred to as ______.

A. Universal asynchronous Rx/TxB. Data communication equipmentC. Universal synchronous Rx/TxD. Data terminal equipment


_______ character signifies the start of the test for Bisync.

A. STXB. ETXC. SOHD. BCC


What is the reason why companding is employed in PCM systems?

A. To overcome impulse noise in PCM receiversB. To allow amplitude limiting in the receiversC. To solve quantizing noise problemD. To protect small signals in PCM from quantizing distortion


What is framing?

A. Is concerned of synchronous systemB. Refers to parallel transmissionC. Is concerned with the boundaries between charactersD. Is concerned with individual bits


The method of determining the bandwidth of any processing system is ______.

A. Bandwidth analysisB. Frequency spectrumC. Spectral analysisD. Frequency analysis


It is a protocol used to connect the other packet switching network.

A. X.25B. X.50C. X.10D. X.75


Slowest communications hardware product.

A. SynchronousB. AsynchronousC. EthernetD. Internet


Highest theoretical frequency that can be processed at a sampling rate without aliasing.

A. Folding frequencyB. Resonant frequencyC. Natural frequencyD. Critical frequency


Data is directly on the transmission cable.

A. AsynchronousB. SynchronousC. BasebandD. Broadband


A source code whose average word length approaches the fundamental limit set by the entropy of a discrete memoryless source.

A. Prefix codeB. Huffman codeC. Entropy codeD. Source code


______ sets the limit on the maximum capacity of a channel with a given noise level.

A. Hartley theoremB. Shannon-hartley theoremC. Nyquist theoremD. Shannon theorem


Gateway can interconnect LANs that have ____ protocols and formats.

A. The sameB. Different or the sameC. Totally differentD. None of these


Steps to follow to produce PCM signal.

A. Quantizing, sampling, and codingB. Sampling, quantizing, and codingC. Sampling, coding and quantizingD. Coding, quantizing and coding


Transmission sent in both directions simultaneously.

A. Full duplexB. Duplex

C. Half duplexD. Simplex


_______ detects the satellite signal relayed from the feed and converts it to an electric current, amplifies and lower its frequency.

A. FeedhornB. Satellite dishC. Satellite receiverD. LNB


What kind of battery panels are used in some advance satellites?

A. Gallium Arsenide solar panelB. Germanium based panelsC. Silicon based panelsD. Gallium Phosphate solar panel


Footprint refers to coverage area in the globe

A. Satellite radiation polarizationB. Satellite navigationC. Satellite radiation patternD. Satellite coverage


Asia Sat I covers how many countries in Asia?

A. 38B. 40C. 44D. 42


Insertion loss of connector-type splices for a single-mode fiber cable.

A. 0.2 dBB. 0.3 dBC. 0.09 dBD. 0.38 dB


A non-coherent light source for optical communications system.

A. PIN DiodeB. ILDC. APDD. LED


Type of fiber that has the highest modal dispersion

A. Step-index multimodeB. Step-index single modeC. Graded index modeD. Graded index multimode


Fiber optic cable operates near _______ frequencies.

A. 800 THzB. 20 MHzC. 200 MHzD. 2 GHz


Lifetime of ILD’s

A. 150,000 hB. 100,000 hC. 50,000 hD. 200,000 h


The sound energy per unit area at right angles to the propagation direction per unit time.

A. Sound intensityB. LoudnessC. Coherence D. Sound stress


_______ is the transmission of sound from one room to an adjacent room thru common walls, floors or ceilings.

A. ReverberationB. RefractionC. Flanking transmissionD. Reflection


The sound power level of a jet plane flying at a height of 1 km is 160 dB. What is the maximum sound pressure level on the ground directly below the plane assuming that the aircraft radiates sound equally in all directions?

A. 59.1 dBB. 69.1 dBC. 79.1 dBD. 89.1 dB


Lowest frequency produced by a musical instrument.

A. FundamentalB. MidrangeC. PeriodD. Harmonic


Sound intensity level is ________.

A. 10 log I/I(ref)B. 10 log I(ref)/IC. 30 log I/I(ref)D. 20 log I/I(ref)


Tendency of sound energy to spread.

A. ReflectionB. DiffractionC. RarefactionD. Refraction


______ used to measure speech volume

A. Volume meterB. Audio frequency meterC. Volume unit meterD. Speech meter


What is the local oscillator frequency range commercial AM broadcast if it is equal to 455 KHz?

A. 540 to 1600 KHzB. 0 to 1600 KHzC. 995 to 2055 KHzD. 0 to 455 KHz


TV channels 2, 4 and 5 are known as ________.

A. Mid band UHFB. Low band UHFC. High band VHFD. Low band VHF


______ is the first component of any MATV system to received broadcast signals.

A. ReceiverB. AntennaC. FilterD. Transmitter


Mechanism or device which enables the TV camera to move in internal and tilting motion.

A. TiltingB. ScannerC. Pan/tilt deviceD. Panning device


The allowable deviation ratio of commercial FM broadcast.

A. 25B. 15C. 5D. 75


______ is the time duration for one horizontal trace.

A. 48µsB. 52 µsC. 62 µsD. 50 µs


Which is atmospheric attenuation?

A. Attenuation due to rainB. Attenuation due to other gasses

C. Attenuation due to mist and fogD. Due to water vapor and oxygen


A microwave system that requires the use of repeater.

A. Intervening terrain is favorableB. Distances involved are greaterC. The required reliability is metD. All of these


What frequency does oxygen causes excessive attenuation

A. 119 GHzB. 183 GHzC. 310 GHzD. 60 GHz


RADAR means

A. Radio detection and ratingB. Radio detection and rangingC. Radio distance and rangingD. Radio delay and ranging


A microwave link between the earth station and the down-town terminal.

A. STLB. UplinkC. DownlinkD. Terrestrial link


The advantage of periscope antenna in microwave

A. Minimize interference to and from other neighboring stationsB. Shorten waveguide linkC. Reduce tower heightD. All of these


Professional Regulations Commission was created under ______.

A. PD 323B. PD 223C. PD 232D. RA 223


The institutionalization of the continuing Professional Education (CPE) Program of the various regulated profession under the supervision of the Professional Regulation Commission.

A. E.O. No. 266B. E.O. No. 626C. E.O. No. 662D. P.D. 381


The basic law providing for the regulation of radio station, communications in the Philippines and other purposes.

A. Act. No.`3846B. D.O. No. 11C. D.O. No. 88D. D.O. No. 5


Listing of the date and time events, programs, equipment, test, malfunctions and corrections in communication system.

A. FileB. DocumentationC. Reporting

D. Log



Extra-terrestrial noise is observable at frequencies from

A. 0 to 20 KHzB. Above 2 GHzC. 8 to 1.43 GHzD. 5 to 8 GHz


Band of light waves that are too short to be seen by human eye.

A. VisibleB. Infrared C. UltravioletD. Amber


Two wires that are bent 90 degrees apart.

A. HertzB. DipoleC. Log-periodicD. Rhomic


The first symbol in the designation of radio emission under the ITU rules to

A. Nature of signals modulating the main carrierB. Type of information to be transmittedC. BandwidthD. Type of modulation of the main carrier


Operating method in which the transmission is made alternately in each direction of a telecommunication channel

A. Semi-duplex operationB. Duplex operationC. Half-duplex operationD. Simplex operation


Production of radiation by a radio transmitting station

A. MonitoringB. EmissionC. RadiationD. Transmission


The third symbol in the designation of radio emission under the ITU rules refers to

A. Type of the modulation of the main carrierB. BandwidthC. Nature of the signals modulating the main carrierD. Type of information to be transmitted


A form of telecommunication for the transmission of transient images of fixed or moving objects.

A. E-mailB. TelevisionC. RadioD. Internet


Radiation pattern of a discone.

A. UnidirectionalB. Bidirectional C. OmnidirectionalD. Figure of eight


Another SEG function that allows a person to be superimposed on another scene.

A. Visual effectB. WiperC. Chroma keyingD. Special effect generation


What signal-to-noise ratio is required for satisfactory telephone services?

A. 50 dBB. 30 dBC. 40dBD. 20 dB


The use of telecommunication for automatic indicating or recording measurement at the distance from the measuring instrument.

A. MonitoringB. TrackingC. TelemetryD. Telecommand


The standard deviation of the variation in the transmission loss of a circuit should not exceed

A. 3 dB

B. 1 dBC. 5 dBD. 0.5dB


Noise caused by the thermal agitation of electrons in resistance.

A. All of theseB. Thermal noiseC. Johnson’s noiseD. White noise


Unity gain antenna

A. IsotropicB. RhombicC. Half-wave dipoleD. Dummy


The series of periodically recurrent pulses is modulated in amplitude by the corresponding instantaneous samples.

A. PFMB. PWMC. PDMD. PAM


This type of transmission permits communication in the frequency range from 30 to 60 MHz and over distances from about 1000 to 2000 km.

A. TroposcatterB. Ionospheric scatterC. DuctingD. Microwave


A region in front of a paraboloid antenna.

A. Transmission zoneB. All of theseC. FraunhoferD. Fresnel


Designates the sensation of low or high in the sense of the base and treble.

A. FrequencyB. IntensityC. PitchD. SPL


A good example of a pilot tone system used in commercial frequency modulation stations.

A. FDMB. Time divisionC. Stereo multiplexingD. Frequency modulation


Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission.

A. RadiationB. NoiseC. Out of the bandD. Interference


A helical antenna is used for satellite tracking because of ______.

A. Broad bandwidthB. Good front-to-back

C. ManeuverabilityD. Circular polarization


Background noise is the same as the following except

A. Impulse noiseB. White noiseC. Thermal noiseD. Gaussian noise


Electronic equipment used to measure standing wave ration.

A. ReflectometerB. WavemeterC. AltimeterD. Multimeter


A single sideband emission in which the degree of carrier suppression enables the carrier to be reconstituted and to be used for demodulation.

A. Reduce carrier single sideband emissionB. Half carrier single sideband emissionC. Full carrier single sideband emissionD. Standard single sideband emission


Station in the mobile service not intended to be used while in motion.

A. Coast stationB. Fixed stationC. Base stationD. Land station


The electric field lines in a plane perpendicular to the earth’s surface.

A. Elliptical polarizationB. Circular polarizationC. Horizontal polarizationD. Vertical polarization


Known to be the first satellite capable to receive and transmit simultaneously.

A. ScoreB. Syncom IC. Telstar 1D. Echo1


A digital carrier facility used to transmit a DSI-formatted signal at 1.544. Mbps.

A. T2B. T1C. T4D. T3


12 voice channels are sampled at 8000 sampling rate and encoded into 8 bit PCM word. Determine the rate of the data stream.

a. 354 kbpsb. 750 kbpsc. 768 kbpsd. 640 kbps


The most common device used as a light detector in fiber optic communications system.

A. LEDB. Darlington phototransistorC. APDsD. PIN diode


Two resistors, 20kΩ, and 50kΩ are at ambient temperature. Calculate for a bandwidth equal to 100 kHz, the thermal noise voltage for the two resistors connected in parallel.

A. 0.4782µVB. 4278 µVC. 4.78 µVD. 47.8 µV


Calculate the energy of the photon of infrared light energy at 1.55µm

A. 1.28x10-19 JB. 1.6 x10-19 JC. 1.22 x10-16 JD. 1.9 x10-14 J


If a fiber optic system has a rise time of 38.55 ns, the source rise time is 12 ns and the detector rise time is 12 ns, what is the cable rise time?

A. 34.61 nsB. 14.55 nsC. 52.55 nsD. 26.25 ns


Nominal voice channel

A. 20 to 20 KHzB. 16 to 16 KHzC. 3 to 3 KHzD. 4 KHz


Two or more antennas separated by 9 wavelengths are used.

A. Hybrid diversityB. Space diversityC. Polarized diversityD. Frequency diversity


Nif stands for

A. Narrow intermediate frequencyB. Noise interference figureC. Noise improvement factorD. Non-intrinsic figure


Any small element of space in the path of a wave may be considered as a source of secondary wavelet.

A. De Morgan’s PrincipleB. Faraday’s LawC. Huygen’s PrincipleD. Fresnel’s Law of optics


Modulation in which the modulated wave is always present.

A. Carrier modulationB. Front-endC. Continuous modulationD. Log-periodic modulation


Atmospheric noise is less at severe frequencies above

A. Audio levelB. 30 MHzC. 10 GHzD. 1 GHz


At height about 180 km above the earth exist only during daylight.

A. F2 layerB. D layerC. E layerD. F1 layer


Radiation characteristics of a dipole

A. Figure of eightB. OmnidirectionalC. BidirectionalD. Unidirectional


Determine the gain of a 6 ft. parabolic dish operating at 1800 MHz

A. 30 dBB. 11.2 dBC. 15.5 dBD. 28.17 dB


An electromagnetic wave is ________ polarized when the electric field lies wholly in one plane containing the direction of propagation.

A. HorizontallyB. LinearlyC. CircularlyD. Vertically


A device that reduces the intensity of light in fiber optics communication systems.

A. ReducerB. Quality factor

C. Optical attenuatorD. Compressor


Propagation mode of microwave in a waveguide is known as _______.

A. TMB. TEC. SWD. TEM


The width of the frequency band which is just sufficient to ensure the transmission of information at the rate and with the quality required under a specified condition and class of emission.

A. Occupied bandwidthB. Reference frequencyC. Necessary bandwidthD. Frequency tolerance bandwidth


A convenient method of determining antenna impedance.

A. Stub matchingB. Reactance circleC. Smith chartD. Trial and error


Which of the following fall under the high frequency band of the radio spectrum?



The electric field lies in a plane parallel to the earth’s surface.

A. Elliptical polarizationB. Horizontal polarizationC. Vertical polarizationD. Circular polarization


The use of telecommunication for the transmission of signals to initiate, modify or terminate functions of equipment at a distance.

A. TrackingB. TelemetryC. TelecommandD. Space telemetry


The product of the power supplied to the antenna and its gain relative to a half-wave dipole in a given direction.

A. Peak envelope powerB. ERPC. Rated powerD. Carrier power’


The Ku-band in the satellite service

A. 14/11 GHzB. 30/17 GHzC. 8/7 GHzD. 6/4 GHz


The sinusoidal carrier is pulsed so that one of the binary states is represented by a carrier while the other is represented by its absence.

A. FSKB. ASKC. PSKD. QAM


Width measured in degrees of a major lobes between end of the love at which the relative power is one half (-3dB) its value from the peak of the lobe.

A. BandwidthB. WavelengthC. RadiationD. Beamwidth


The most common unit of noise measurement in white noise voltage testing.

A. NPRB. dBmC. dBWD. dBrn


Any governmental office responsible in discharging the obligations undertaken in the convention of the ITU and the regulation.

A. AdministrationB. The unionC. CountryD. Telecommunications office


A large speaker having a large diameter (15 cm and above)

A. Coaxial speakerB. WooferC. TweeterD. Trixial speaker


Coaxial lines are used on those systems operating _______.

A. Below 2 GHzB. At 300 MHzC. Above 10KHzD. Above 10GHz


Determine the dynamic range for a 10 bit sign magnitude code.

A. 1023B. 425C. 511D. 756


A coherent binary phase shift keyed BPSK transmitter operates at a bit rate of 20 Mbps with a carrier to noise ratio C/N of 8.8dB. Find Eb/No.

A. 73 dBB. 62.4 dBC. 81.8 dBD. 8.8 dB


Receives and collects satellite signals form a broadcast satellite.

A. LNBB. Yagi-Uda arrayC. Satellite receiverD. Satellite disk


What is the effect in over modulated amplitude modulated radio broadcasting transmission?

A. Interference to adjacent channel

B. Higher fidelityC. Increase noiseD. Higher audio signal


Average power of a radio transmitter supplied to the antenna transmission line by a transmitter during one radio frequency cycle taken under the condition of no modulation.

A. Peak envelop powerB. Rated powerC. Carrier powerD. Mean power


A method of expressing the amplitude of complex non-periodic signals such as speech.

A. FrequencyB. WavelengthC. VolumeD. Pitch


A government regulation in telecommunication which provide policy to improve the provision of local exchange carrier service.

A. E.O. 109B. Act 3846C. E.O. 59D. E.O. 546


Radio communication operation service between mobile and land stations or between mobile stations.

A. Land mobile satellite serviceB. Maritime mobile serviceC. Mobile serviceD. Land mobile


The smaller the f rating, the _____ light that lens can take in.

A. MoreB. IntenseC. Less D. Same


A radio communications service use in radio regulation between specified fixed points provided primarily for the safety of air navigation and for the regular efficient and economical air transport.

A. Space operation serviceB. Space serviceC. Aeronautical mobile serviceD. Aeronautical fixed service


Harmonic suppressor connected to an antenna.

A. High pass filterB. Low pass filterC. Tank circuitD. M-derived filter


The tendency of the sound energy to spread.

A. RarefactionB. ReflectionC. RefractionD. Diffraction


An earth satellite whose period of revolution is equal to the period of rotation of the earth about its axis.

A. GeosynchronousB. SteerableC. PassiveD. Active


A figure of merit used to measure the performance of a radiation detector.

A. Noise equivalent powerB. Ripple factorC. Safe factorD. Quality factor


Radio wave concentration in the direction of the signal emitted by a directional antenna.

A. Back lobe radiationB. Side lobe radiationC. Major lobe radiationD. Transmitted signal


What is the channel bandwidth of a standard analogue telephone system?

A. 300-500 HzB. 1200 kHzC. 100-300 HzD. 300-3400 Hz


A satellite receives an uplink frequency of _______ MHz from a ground station of 3700 MHz

A. 8150 MHzB. 1475 MHzC. 2225 MHz

D. 5925 MHz


The outer conductor of a coaxial transmission line is always grounded at the

A. Input onlyB. Input and outputC. Output onlyD. Point of high SWR


Sound intensity is given as

A. df/dPB. dE/dpC. dA/dPD. dP/dA


The lowest frequency produced by an instrument.

A. HarmonicB. FundamentalC. MidrangeD. 0 Hz


The reflector and director of an antenna array are considered as

A. Parasitic elementsB. Transcendental elementsC. Feed-pointsD. Driven elements


The core of the optical fiber has ______.

A. A medium index of refractionB. A lower index of refraction than the claddingC. A lower index of refraction than airD. A higher index of refraction than the cladding


What makes an antenna physically long but electrically short?

A. Top loadingB. Adding C in seriesC. Adding L in seriesD. All of these


An AM transmitter is rated 100W at 100% modulation. How much power required for the carrier?

A. 33.33 WB. 66.66 WC. 83.33 WD. 100 W


Used for time division multiplexing.

A. Frequency modulationB. Pulsed modulationC. SSBD. Amplitude modulation


A means of beyond the line-of-sight propagation of microwave signal.

A. Space waveB. Microwave linkC. TroposcatterD. Point-to-point


Which of the following refers to the smallest beam of satellite antenna’s radiation pattern?

A. Hemispheric beamB. Spot beamC. Zone beamD. Global beam


Theoretical gain of a hertzian dipole

A. 0 dBB. 1.76 dBC. 3 dBD. 2.15 dB


Satellite system or part of a satellite system, consisting of only one satellite and the operating earth station.

A. Satellite systemB. Satellite networkC. Space systemD. Multi-satellite link


The difference between the original and reconstructed signal gives rise to

A. S factorB. Quantizing noiseC. S/ND. Fade margin


An area in the memory used for temporary storage of information, on “Last in First out” basis.

A. Core

B. RegisterC. FlagD. Stack


Refers to a land station in a maritime mobile service

A. Coast stationB. Ship earth stationC. Coast earth stationD. Maritime station


Modulation in which no signal is present between pulses

A. Pulse modulationB. QAMC. PSKD. FSK


In the designation of bandwidth and emission, what letter in the first symbol represents a double-sideband type of modulation?

A. AB. BC. CD. H


Loss due to the diffraction of light when it strikes on the irregularities formed during the manufacturing process of the fiber optics.

A. Absorption lossB. AttenuationC. Bending lossD. Rayleigh scattering loss


What is the unit of electric field strength?

A. Watt/meterB. Ohms/meterC. Ampere/meterD. Watt/meter2

E. No answer


Refers to the first generation of local loop system in telecommunication technology.

A. GSMB. DECTC. Analogue cellularD. TACS


An area on the surface of the earth within which the bore sight of the steerable satellite beam intended to be pointed

A. Effective boresight areaB. Countour boresight areC. Coordination boresight areD. Equivalent boresight area


For a sample rate of 40 kHz, determine the maximum analog input frequency



An antenna that can only receive a television signal.

A. Isotropic antenna

B. TVROC. Reference antennaD. Yagi antenna


Halo is also called

A. FlareB. Dark currentC. Glitch D. Ghost



Space diversity transmission means transmitting and receiving on _______.

A. Two or more antennas operating on two different frequenciesB. Two or more identical frequenciesC. Two or more antennas operating on the same frequencyD. Two or more different frequency


An increase in the effective power radiated by an antenna in a certain desired direction at the expense of power radiated in other directions.

A. Antenna gainB. Antenna back lobe rationC. Antenna total rationD. Antenna efficiency


A radio land station in the land mobile service

A. Mobile stationB. Land stationC. Base stationD. Ship earth station


A major and basic advantage for the use of a klystron.

A. High powerB. EfficiencyC. Lesser noiseD. Cheaper


A band where most military satellite often operate

A. KuB. CC. XD. L


The final power amplifier in an FM transmitter usually operates class ______.

A. ABB. CC. BD. A


In television broadcasting vivid strong colors are often referred as _______.

A. SaturationB. HueC. ChrominanceD. Luminance


Where do the maximum current and minimum voltage values on a resonant Hertz dipole exist?

A. Center of the antennaB. Near the end of the antenna

C. Near the center of the antennaD. Ends of the antenna


How can the antenna efficiency of an HF grounded vertical antenna be made comparable to that of a half-wave antenna?

A. By lengthening the verticalB. By installing a good ground radial systemC. By shortening the verticalD. By isolating the coax shield from ground


At what distance is VHF propagation normally limited?

A. Around 500 milesB. Around 1500 milesC. Around 2000 milesD. Around 1000 miles


What is meant by the term antenna efficiency?

A. Efficiency = effective radiated power/transmitter output x 100%B. Efficiency = radiation resistance/ transmission resistanceC. Efficiency = total resistance/radiation resistance x 100%D. Efficiency = radiation resistance/total resistance x 100%


This is referred to as a fixed radio station that broadcasts program material from studio to transmitter by radio link.

A. Aural BC intercity relayB. Aural broadcast STLC. Shortwave stationD. Remote-pickup


What law does a light traveling in air optical fiber follow?

A. MillmanB. Snell’sC. Maxwell D. Huygen


Which of the following is designated as the international distress, safety and calling frequency for radio telephony for stations of the maritime mobile service when using frequencies in the authorized bands between 156 and 174 MHz?



A device that connects two dissimilar networks and performs the protocol conversion.

A. Gateway B. CouplerC. TransformerD. Converter


The use of telecommunication for the transmission of signals to initiate, modify or terminate functions of equipment at a distance.

A. Tracking B. space command C. Telecommand D. Trunking


Best described a dip-meter.

A. A variable LC oscillator with metered feedback currentB. An SWR meterC. A counterD. A field strength meter


Refers to an emission designation for facsimile?

A. J3E and F4EB. A3J and A4EC. A3E and F3CD. R3E and A3E


How does a SSB transmitter output power normally expressed?

A. Average powerB. In terms of peak envelop powerC. In terms of peak-to-peak powerD. Peak power


In satellite communication, the geostationary satellites are conveniently located with respect to the equator at _______.

A. 45 degrees latitudeB. 90 degrees latitudeC. 0 degrees latitudeD. 5 degrees latitude


Known as the technique for adding a series inductor at or near the center of an antenna element in order to cancel the capacitive reactance of an antenna.

A. DipoleB. Center loadingC. Reflector D. loading coil


What is meant by the term antenna bandwidth?

A. Antenna length divided by the number of elements.B. The angle between the half-power radiation pointsC. The frequency range over which and antenna can be expected to perform wellD. The angle formed between two imaginary line drawn through the ends of the elements


A multiple access technique used in GSM cellular system

A. TACSB. FDMAC. TDMAD. CDMA


Refers to an effect of selective fading.

A. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station.

B. A fading effect caused by small changes in beam heading at the receiving station.C. A fading effect caused by the time differences between the receiving and transmitting

stations.D. A fading effect caused by large changes in the height of the ionosphere, as experienced at

the receiving station.


Where the voltage node of a half-wave antenna does exists?

A. At feed pointB. Near the centerC. At centerD. Near the feed point


This is a flexible vertical rod antenna commonly used on mobiles.

A. MarconiB. HertzC. WhipD. Ground plane


Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation.

A. Carrier powerB. Rated powerC. Peak envelop powerD. Mean power


_______ is a major cause of the sporadic-E condition

A. Temperature inversionsB. SunspotsC. MeteorsD. Wind shear


Which of the following refers to a double side band full carrier?

A. A3EB. A3JC. F3D. R3A


What is the basic qualification of an applicant for public carrier network before a certificate of public convenience or a provisional authority is issued?

A. FranchiseB. SEC documentC. Business permit

D. Radio station license


How wide is the spectrum bandwidth of a single GSM carrier?



With which emission type is the capture-effect most pronounced?

A. CWB. FMC. SSBD. AM


What is a dummy antenna?

A. One which is used as a reference for gain measurementsB. And antenna used for hand-held radio C. An non-directional transmitting antennaD. A non-radiating load for a transmitter used for testing


Best description of a collinear and broadside antenna radiation pattern.

A. BidirectionalB. Perfect circleC. UnidirectionalD. Omnidirectional


A satellite beam that covers almost 42.4% of earth’s surface.

A. Spot beamB. Global beamC. Zone beamD. Hemispheric beam


The modulation technique used by GSM cellular system

A. Phase shift keyingB. Frequency shift keyingC. Gaussian minimum shift keyingD. QAM


________ generates light beam at a specific visible frequency.

A. Glass fiberB. InfraredC. Light wavesD. Laser


The most common application of satellites

A. SurveillanceB. ReconnaissanceC. Defense systemsD. Communication


Referred to the dielectric constant of a transmission line material.

A. Inductance and capacitanceB. Velocity factorC. Characteristic impedanceD. Propagation velocity


Referred to as a ferrite device that can be used in lieu of a duplexer to isolate a microwave transmitter and receiver when both are connected to the same antenna.

A. Isolator B. CirculatorC. CouplerD. Diode.


_______ is more prevalent in analog signals that have steep slopes or whose amplitudes vary rapidly.

A. Peak limitingB. Quantization noiseC. Granular noiseD. Slope overload


Station located on an object which is beyond and is intended to go beyond the major portion of the earth’s atmosphere.

A. Terrestrial stationB. Space stationC. Satellite stationD. Mobile satellite station


A radio frequency in the ultra-high frequency band of the radio spectrum band.

A. 235.50 MHzB. 450.50 MHzC. 150.50 GHzD. 0.31250 GHz


Technical study which deals with production, transport and delivery of a quality signal from source to destination.

A. Transmission system engineering B. Communication system engineeringC. Telephony engineering D. Telegraphic engineering


It is used to connect computers in the same building or in same area

A. MANB. LANC. SWITCHD. WAN


Referred by radio regulation as the station in the mobile service not intended to be used while in motion.

A. Fixed stationB. Base stationC. Land stationD. Coast station


What is the mixing process?

A. Distortion caused by auroral propagationB. The combination of two signals to produce sum and difference frequencies.C. The elimination of noise in wideband receiver by phase differentiationD. The elimination of noise in a wideband receiver by phase comparison


Which of the following systems is not used in radio detection and ranging?

A. Frequency shiftB. Frequency modulationC. Pulse radarD. Amplitude modulation


Considered as the main source of an internal noise.

A. Device imperfectionB. Thermal agitationC. Temperature changeD. Flicker


In shipboard satellite dish antennas system, azimuth is referred as the _______.

A. 0 to 90 degreesB. Vertical aiming of the antennaC. North to EastD. Horizontal aiming of the antenna


What is the period of a wave?

A. The number of degrees in tone cycleB. The number of zero crossing in one cycleC. The amplitude of the waveD. The time required to complete one cycle


Is the total useful information processed or communicated over a specific amount of time

A. Baud rateB. Bit rateC. Information theoryD. Throughput


What is the approximate percentage of earth coverage of a geostationary satellite at zero degree elevation?

A. 33.3%B. 45.2%

C. 42.5%D. 30.5%


This refers to an area in the memory used for temporary storage of information on the basis of “Last in First out”.

A. CoreB. RegisterC. FlagD. Stack


What is a driven element of an antenna?

A. Always the rearmost elementB. Always the forwardmost elementC. The element fed by the transmission lineD. The element connected to the rotator


Which of the following term best described the overload distortion?

A. Peak limitingB. Quantization noiseC. Granular noiseD. Slope distortion


What do you mean by the outward flow of and energy from any source in the form of radio waves?

A. RadiationB. EmissionC. EncodingD. Tracking


Refer to the deviation of the operating frequency of a crystal oscillator from its nominal value due to temperature variations.

A. DriftB. Flash overC. Frequency deviationD. Deviation ratio


Find the product of the following binary number 100 to 101.

A. 11000B. 10100C. 10010D. 11100


Which of the following is and impedance matching ration of coax balun?

A. 2:8B. 1:2C. 4:1D. 2:1


Quantity that do not change when a beam of light enters one medium to another.

A. FrequencyB. WavelengthC. DirectionD. Speed


Which of the following described the very early standard that defines binary digits as space/mark line condition and voltage levels?

A. V.4

B. V.2C. V.1D. V.5


A form of single sideband emission where the degree of carrier suppression enable the carrier to be reconstituted and be used for demodulation.

A. Half carrier single sideband emissionB. Full carrier single sideband emissionC. Reduced carrier single sideband emissionD. Double sideband emission


An instrument for recording waveforms of audio frequency.

A. OscilloscopeB. PhonoscopeC. RadioscopeD. Audioscope


How much is the required minimum power output of an international AM BC stations?

A. 5 kWB. 30 kWC. 10 kWD. 50 kW


What is the equivalent of decimal 51 in binary?

A. 111011B. 110011C. 111001D. 100011


One of the first satellite system catering personal based communications services scheduled for operation.

A. Iridium systemB. Plutonium systemC. Indium systemD. Gallium system


What do you call a circuit that controls the magnetron output?

A. InverterB. ImpellerC. ModulatorD. Converter


Known as the satellite transmitted signal form a satellite transponder to earth’s station.

A. UplinkB. Down linkC. RHCPD. Vertically polarized


Which of the following colors of light rays has the shortest wavelength?

A. YellowB. VioletC. RedD. Blue


Antenna which is not properly terminated

A. IsotropicB. Non-resonant

C. Whip D. Resonant


Term in communication which is referred, “to send out in all direction”.

A. AnnounceB. BroadcastC. TransmitD. Media


At the ends of a half-wave antenna, what values of current and voltage exist compared to the remainder of the antenna?

A. Minimum voltage and minimum currentB. Equal voltage and currentC. Minimum voltage and maximum currentD. Maximum voltage and minimum current.


One of the following stands for SONET acronym in telecommunication

A. System optical networkB. Simple operation networkC. Synchronous optical networkD. System operating network


How can intermodulation interference between two transmitters in close proximity reduced or eliminated?

A. Through installing a band-pass filter in the antenna feed lineB. Through installing terminated circulator or ferrite isolator in the feed line of the

transmitter and duplexerC. By using a class C final amplifier with high driving powerD. By installing a low-pass filter in the antenna feed line


What propagation condition is usually indicated when a VHF signal is received from a station over 5000 miles away?

A. MoonbounceB. D-layer absorptionC. Tropospheric ductingD. Faraday rotation


In radio High frequency communications the higher the radio frequency the ______.

A. Higher it can reachB. Shorter it can reachC. Effect is nullD. Longer it can reach


The signal to noise ratio that is required for a satisfactory television reception.

A. 30 dBB. 40 dBC. 10 dBD. 20 dB


What is meant by referring to electromagnetic waves as horizontally polarized?

A. The electric field is parallel to the earth B. Both the electric and magnetic fields are verticalC. Both the electric and magnetic fields are horizontalD. The magnetic fields is parallel to the earth


What is emission F3F?

A. FacsimileB. Modulated CW

C. RTTYD. Television


How can receiver desensitizing be reduced?

A. Increase the receiver bandwidthB. Ensure good RF shielding between the transmitter and receiverC. Increase the transmitter audio gainD. Decrease the receiver squelch, gain.


Circuit used to amplify the optical signal in fiber optics communications links.

A. AttenuatorB. Optical repeaterC. Optical amplifierD. Generator


What do you call the single booster installed on the antenna dish of satellite receiver?

A. Low noise amplifierB. Single amplifierC. Noise amplifierD. Rectifier


Term for the transmission of printed pictures by radio?

A. FacsimileB. ACSSBC. XerographyD. Television


An interfering current in a telegraph or signaling channel due to telegraph or signaling current by another channel.

A. CrosstalkB. Noise currentC. CrossfireD. Intermodulation


Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150 MHz) marine-band receiver?

A. In the ionosphereB. In the receiver rear endC. In the receiver front endD. In the atmosphere


Known as the data transfer scheme that used handmaking principle.

A. Synchronous data transfer schemeB. DMA data transfer schemeC. Asynchronous data transfer schemeD. Uninterrupted data transfer scheme


Type of modulation used in TV broadcast visual transmitter.

A. Pulse modulationB. DSBFCC. Vestigial sidebandD. SSBFC


A transmitter supplies 8 kW to the antenna when it is unmodulated, determine the total radiated power when modulated at 90%.

A. 5 kWB. 20 kW

C. 15 kWD. 8.36 kW


Best describe as an amplifier used in radio telephony.

A. MagnifierB. Class BC. Class CD. Class A


The latest government regulation in the telecommunication which provides policy for the provision of local exchange carrier service.

A. E.O. 546B. E.O. 109C. Act 3948D. E.O. 59


Referred to as the stage in the radio receiver that contributes most of the noise.

A. IF amplifierB. Supply stageC. Speaker D. Mixer


The frequency tolerance of an AM radio broadcast station

A. 200 HzB. 2000 HzC. 20 HzD. 2 Hz


What are electromagnetic waves?

A. A wave consisting of two magnetic fields at right angles to each otherB. A wave consisting of an electric field and a magnetic field at right angles to each other.C. Alternating currents in the core of an electromagnetD. A wave consisting of two electric fields at right angles to each other


What is the frequency range of C-band?

A. 10.95 to 14.5 GHzB. 27.5 to 31 GHzC. 3.4 to 6.424 GHzD. 1.53 to 2.7 GHz


Determine from the following the basic mode of transmission system in the public data network in which data are transferred from the source to the network and from the network to the destination in the frame format.

A. Voice modeB. Asynchronous modeC. Synchronous modeD. Packet mode


Refers to a type of beam antenna which uses two or more straight elements arranged in line with each other.

A. Dipole antennaB. Yagi antennaC. Whip antennaD. Rhombic antenna


What is a frequency discriminator?

A. A circuit for filtering two closely adjacent signalsB. A circuit for detecting FM signals

C. An FM generatorD. An automatic bandswitching circuit.


These are used to connect non-ISDN equipment ot ISDN line.

A. DigipeatersB. Terminal adaptersC. Local repeatersD. Terminal repeaters


The executive branch of government in charge of policy making in the telecommunications.

A. National telecommunications commissionB. Telecommunications control bureauC. Department of transportation and communicationsD. Bureau of telecommunication



When adjusting an RF filter on a transmitter using a dummy load, how much watts dissipation should it stand to test a 150 watts transmitter?

A. 75 wattsB. 300 wattsC. 50 wattsD. 150 watts


When does broadcast station conduct and equipment test?

A. During day timeB. During night timeC. At any time

D. During experimental period


Channel 7 of the regular television channel belongs to which band?

A. Low VHF bandB. High VHF bandC. Low UHF bandD. High UHF band


Which of the following is one of the possible causes for a slow drift of frequency in a self-exited transmitter oscillator circuits resulting to a poor frequency stability?

A. Poor soldered connectionsB. Power supply voltage changesC. Loose connections in the oscillator, amplifier, or antenna circuitsD. DC and RF heating of resistors, causing then to change values.


A third symbol radio emission which represent telephone transmission including sound broadcasting.

A. WB. FC. CD. E


Which of the following is not a common microwave application?

A. RadarB. Data transmissionC. Space communicationsD. Mobile radio


Which of the following is referred to as a radio emission without sidebands

A. AnalogB. CarrierC. DataD. Voice


Ho w many times bigger does the bandwidth of a fiber optic multimode have over a cable?

A. 50 times biggerB. 100 times biggerC. 10 times biggerD. 5 times bigger


Type of antenna which is normally used for satellite tracking service.

A. OmniB. HelicalC. YagiD. Dipole


One of the following is referred to as a major component of an optical time domain reflectometer

A. Pulse generator and vertical plateB. Laser and horizontal plateC. Pulse generator laserD. Vertical and horizontal plate


One of the commonly used domain in the internet service.

A. YahooB. httpC. comD. www


What is meant by the term radiation resistance for an antenna?

A. The resistance in the trap coils to received signalB. An equivalent resistance that would dissipate the same amount of power as that radiated

from an antennaC. The specific impedance of the antennaD. Losses in the antenna elements and feed line


Referred to an oscillator signal “leak through” from a properly neutralized amplifier such as a master oscillator power amplifier.

A. CarrierB. Stray signalC. Back waveD. Loss wave


An advantage of optic fiber rejecting an induced noise signals from magnetic field or solar storms flux.

A. Electric hazardB. Cross talkC. Immunity to noiseD. Shielding


What kind of effect is referred to a varying light producing a varying voltage output of a detector?

A. Current effectB. Voltage effectC. Resistive effectD. Photovoltaic effect


______ is known to be the first satellite capable of receiving and transmitting simultaneously.

A. Syncom IB. Telstar IC. Score D. Aguila


The extremely high frequency (EHF) band is in the radio spectrum range of _______.

A. 30 to 300 kHzB. 30 to 300 GHzC. 3 to 30 MHzD. 3 to 30 GHz


One of the following is not among the advantages of series modulation

A. No transformerB. Suppressed white noiseC. SimpleD. Modulates any frequency


What do you call the service area of a standard AM broadcast where fading is allowed but not objectionable co-channel interference?

A. ExperimentalB. SecondaryC. TertiaryD. Primary


A third symbol emission which represent television.

A. CB. DC. FD. A


In telecommunications when we call data communications it means the transmission of________.

A. Voice and videoB. VoiceC. VideoD. Computer data


If frequency range of 401.000MHz to 401.050MHz has to be channelized at 12.5 kHz between channels, what is the center of its first channel from the lower limit?

A. 401.125MHzB. 401.00625MHzC. 401.025MHzD. 401.0125MHz


Determine the effective radiated power of 20 kW TV broadcast transmitter whose antenna has a field gain of 2.

A. 40 kWB. 80,000 wattsC. 40,000 wattsD. 8,000 watts


In indication signal for a handshake form the DCE to the DTE in response to an active condition for the request to send a signal.

A. Data transmissionB. Clear to sendC. Receive dataD. Data set ready


In amplitude modulation technique the unmodulated carrier is referred to as having ______.

A. 100% modulationB. 0% modulationC. 50% modulatedD. Over modulated


One of the following is not among the major components required on board ship under the global maritime distress and safety system.

A. On board radio facilitiesB. Radio operator telegraphy onboardC. Shore base facilitiesD. Radio personnel on board


In what form does the information of data communications is transmitted between two points?

A. Alphanumeric formB. Alphabetic formC. Numeric formD. Binary form


Width of frequency band just enough to ensure the transmission of information at a required rate and quality required, and under a specified condition and class of emission.

A. Occupied bandwidthB. Transmission bandwidthC. Necessary bandwidthD. Frequency bandwidth


Refers to one of the front end circuit of a VHF TV superheterodyne receiver which is usually a separate circuit coupled to the mixer.

A. Antenna feed

B. AGCC. RF amplifierD. Local oscillator


All bits in character are sent and received ______ in serial port.

A. In groups of 3 bitsB. One at a timeC. In groups of 2 bitsD. Simultaneously


One of the following is a possible cause of an abrupt frequency variation in a self exited transmitter oscillator circuits resulting to a poor frequency stability to hold a constant frequency oscillation.

A. Heating and expansion of oscillator coilB. DC and RF ac heating of resistors which cause change in valuesC. Heating of capacitor in the oscillatorD. Loose connections in the oscillator, amplifier, or antenna circuits.


Which of the following parts of the radio receiver represent the component that extracts the desire RF signal from the electromagnetic wave?

A. AF amplifierB. AntennaC. DetectorD. Crystal


It is an average power of a radio transmitter supplied to the antenna transmission line taken during a long sufficient interval of time and compared with the lowest frequency encountered in the modulation, taken under the normal operating conditions.

A. Carrier powerB. Rated powerC. Mean power

D. Peak envelop power


Determine from the following radio frequency that falls under the very high frequency band of the radio spectrum.



What is the typical number of bits in a static memory location?

A. 1B. 2C. 16D. 8


What controls the contrast of a television cathode ray picture?

A. AFC B. video stage gainC. Audio gain controlD. CRT bias


Determine the dB gain of a receiving antenna which delivers a microvolt signal to a transmission line over that of an antenna that delivers a 20 microvolt signal under identical circumstances.

A. 10 dBB. 6 dBC. 3 dBD. 8 dB


Refers to one of a commonly used internet service domain.

A. wwwB. httpC. govD. infoseek


A law that specifically requires the service of a duly registered electronics and communications engineer in the designing installation and construction, operation and maintenance of radio stations.

A. Act 3846B. LOl 1000C. R.A. 5734D. Dept. order 88


Which band does channel 14 of the television channel belong?

A. High VHF bandB. EHF bandC. UHF bandD. Low VHF band


How many ship’s area is designated in the implementation of the global maritime distress and safety system.

A. FourB. SixC. ThreeD. Two


What kind of receiver is used in conventional telephone handset?

A. CapacitorB. ElectromagneticC. CarbonD. Ceramic


Determine the lower half-power frequency of a class-C amplifier having upper half-power frequency of 10.025 MHz, a resonant frequency 5 MHz and a circuit Q of 10.

A. 1.0025 MHzB. 10.525 MHzC. 0.5 MHzD. 10 MHz


This is referred to a product of simultaneous frequency and amplitude modulation or a carrier frequency variation which produces unwanted distortion.

A. Absorption modulationB. Simultaneous modulationC. Dynamic instabilityD. Series modulation


Main basic components of a data communication are composed of the following.

A. Computer, modern and routerB. Computer, bridge and gatewayC. Transmitter, channel and receiverD. Transmitter, computer and modem


The international radio consultative committee is referred to in international radio communication as ______.

A. IRCCB. ITUC. IRRD. CCIR


Refers to a continuous tone generated in a local exchange terminal through a combination of two frequencies 350 Hz, and 440 Hz.

A. Busy toneB. Call waiting toneC. Dial toneD. Standard tone


One of the advantages of fiber optic which is referred to the volume of capacity of signals it can carry.

A. SecurityB. WeightC. BandwidthD. Physical size


Assume a frequency range of 401.000 MHz to 401.050 MHz, if you apply 25 kHz channeling plan, determine the center frequency of the first channel from the lower limit.


50. 50 ECE Board Exam April 1998

The stability of transmitted signal from a simple Hartley oscillator single transmitter which is coupled to and antenna wire affected by ______.

A. Chirping of oscillatorB. Closer coupling between the oscillator and the antenna.C. Location of antennaD. Material of antenna


Refers to the first symbol in an emission designation with an amplitude modulated main carrier represented by letter H.

A. Single sideband suppressed carrierB. Double sideband full carrierC. Independent sidebandD. Double sideband


Assume a frequency range of 405.0125 MHz to 405.0875 MHz and 25 kHz channeling plan, determine the center frequency of the second channel from the lower limit.



An entity, relying on the transmission, switching and local distribution facilities of local exchange and inter-exchange operators, and overseas carriers, offers enhanced services beyond those ordinarily provided by such carriers.

A. International carrierB. Value-added service providedC. Inter-exchange carrierD. Local exchange carrier


Which of the following refers to full duplex transmission?

A. One at a time transmissionB. Two transmission mediumC. Intermittent transmissionD. Two way simultaneous transmission


What is the first symbol of a radio signal transmission having an amplitude modulated signal carrier, double side band?

A. CB. BC. HD. A


Best choice of transmission line component to couple a coaxial line to a parallel-wire line

A. ShortingB. BalunC. Slotted lineD. Directional coupler


Which of the following refers to the video signal amplitude that determines the quality of the picture?

A. ChrominanceB. LuminanceC. BrightnessD. Contrast


________ is the method of encoding audio signals used in US standard 1544 kbit/s 24 channel PCM systems.

A. Shannon’s lawB. A-lawC. Newton’s lawD. Mu-law


In radio regulation, the first symbol in the designation of radio emission is ______.

A. Bandwidth B. Nature of signal(s) modulation the main carrierC. Type of modulation of the main carrierD. Type of information to be transmitted


Who is the principal administrator of republic act 7925?

A. BOCB. DOTCC. CongressD. NTC


What is the term for the ration of the radiation resistance of an antenna to the total resistance of the system?

A. Effective radiated powerB. BeamwidthC. Radiation conversion lossD. Antenna efficiency


Where does the AM broadcast band located in the spectrum band?

A. HF bandB. VHF bandC. LF bandD. MF band


What determines the velocity factor in transmission line?

A. The center conductor resistivityB. Dielectrics in the lineC. The termination impedanceD. The line length


Refers to an address that identifies a server on the network and a particular document on the server

A. HypertextB. HTMLC. Wide area networkD. Uniform resource locator


Type of emission produced by one of the early radio transmitter in trains of damped RF ac waves where its oscillator is coupled to a long wire antenna, normally used in radio telegraph and having sidebands on its carrier.

A. Digital emissionB. Key emissionC. Cycle emissionD. Spark emission


Is a kind of satellite which has a period of revolution equivalent to the period of rotation of the earth about its axis.

A. Passive satelliteB. Synchronous satelliteC. Active satelliteD. Geosynchronous satellite


Electromagnetic waves of frequencies arbitrarily lower than 3,000 GHz, propagated in space without artificial guide.

A. Space wavesB. Terrestrial wavesC. MobileD. Hertzian waves


Frequencies above ______ kHz, are referred to as the radio frequencies.

A. 20 B. 2C. 10

D. 200


Who is responsible in the correctness and accuracy of transmitted information content over a data communication?

A. The channelB. The transmitter and receiverC. The modemD. The bridge


What is meant by the term deviation ratio?

A. The ratio of the carrier center frequency to the audio modulating frequencyB. The ratio of the highest audio modulating frequency to the average audio modulating

frequencyC. The ratio of the maximum carrier frequency deviation to the highest audio modulation

frequencyD. The ratio of the audio modulating frequency to the center carrier frequency


A quarter wavelength devices made of crystalline calcite that changes polarization in the optic fiber communication.

A. IsolatorB. RetarderC. PolarizerD. Filters


Known as the maritime communications law which was enacted December 5, 1927

A. R.A. No. 109B. R.A. No. 3396C. R.A. No. 7925D. R.A. No. 3846


How do you transmit through multiplexing, a thousand of voice channel information over a single fiber optic using one wavelength?

A. Polar divisionB. Time divisionC. Fiber divisionD. Frequency division


In regulation of public telecommunications carrier such as in the evaluation of new entrant, the following consideration shall be given emphasis to _______.

A. Legal, technical and citizenshipB. Technical, citizenship and kind of serviceC. Citizenship, capacity and financialD. Technical, legal and financial


One of the following is a high powered RF ac basic transmitter that has two or more stages, the oscillator stage which determines the frequency operation and RF amplifier stage or stages that develop the high power output. The purpose of which is to develop a good frequency stability.

A. GoldsmithB. MOPAC. Alexanderson D. Hartley


What is the meaning of the term velocity factor of a transmission line?

A. The index of shielding for coaxial cable B. The velocity of the wave on the transmission line multiplied by the velocity of light in

vacuumC. The ratio of the characteristic impedance of the line to the terminating impedanceD. The velocity of the wave on the transmission line divided by the velocity of light in a

vacuum


Which of the following determines the characteristics of a transmission line?

A. InductanceB. Capacitance C. Physical dimensionD. Length


One of the following is among the types of fiber optics used in electronics communication.

A. Step-index multimodeB. Graded-index multimodeC. Semi-graded multimodeD. Single mode


Which of the following refers to the smallest beam of a satellite antenna’s radiation pattern

A. Global beamB. Spot beamC. Zone beamD. Hemispheric beam


One of the FM signal generator control which varies the phase of the modulating voltage applied to the oscillator of the sweep generator

A. Band controlB. Phase controlC. Marker amplitude controlD. Sweep output control


What consists the front-end circuit of a VHF TV superheterodyne receiver?

A. Mixer, RF amplifier and AFC?B. RF amplifier, Band pass filter and mixer

C. Local oscillator, mixer and RF amplifierD. Local oscillator, AGC and antenna


One of the following prevents a transmitter from emitting a signal that interferes with other stations on frequency during the test.

A. Use of low height antennaB. Use of grounded antennaC. Use of dummy antennaD. Use of shielded antenna radiator


A transmission line consisting of two conductors that have equal resistance per unit length.

A. Unbalanced lineB. Open-wire lineC. Balanced lineD. Coaxial line


How do you eliminate radio frequency variation of an oscillator transmitter caused by its supply voltage?

A. Use new power supply B. Lossen power supply shieldingC. Use of regulated power supplyD. Use of high capacitor in the supply circuit


Which of the following is not common transmission line impedance?

A. 50 ohmsB. 120 ohmsC. 75 ohmsD. 650 ohms


How do you reduce the loss that is produced when light strikes a flat polished end of a fiber optic?

A. By painting the surfaceB. By inclining the surfaceC. By coolingD. By application of antireflection coating


Best reason for pressurizing waveguides with dry air

A. To maintain propagationB. To maintain temperature of the waveguideC. To reduce the possibility of internal arcingD. To increase the speed of propagation


What is the device used in fiber optic communication which consist of a receiver transmitter use to clean up and amplify digital data moving in one direction and another in the opposite direction?

A. Optic compressorsB. Optic retardersC. Optic isolatorD. Optic regenerators


Which of the following refers to the first active satellite?

A. Telstar IB. Echo IC. Intelsat ID. Sputnik I


In modulation technique, which of the following is referred to audible pitch?

A. WidthB. FrequencyC. HarmonicD. Amplitude


What do you call the phenomenon in digital circuits that describe the duration of time a digital signal passes a circuit?

A. Transmission timeB. Elapsed timeC. Propagation delayD. Travel delay


What is the major cause of atmospheric or static noise?

A. SunspotsB. AirplanesC. Meteor showersD. Thunderstorm


Which of the following is not referred to as data terminal equipment?

A. Telephone setB. PrintersC. ModemD. Computer


_______ is referred as the difference between available power and power budget?

A. Fade marginB. Power marginC. Nominal gainD. Power dissipation


The conversion of digital signal into analog for purposes of transmitting into the telephone line is done through ______.

A. ISDNB. RadioC. RS232CD. Modem


Refers to the duration occupancy period of call during its use.

A. Occupancy periodB. Traffic timeC. Use timeD. Holding time


In data communication the transmission of binary signals will require _______.

A. Same bandwidth as analogB. More bandwidth than analogC. Less bandwidth than analogD. Bigger cable diameter


Assuming a UHF frequency range of 405.0125 MHz to 405.0875 MHz at 25 kHz channeling plan, how many channels can you produce?

A. 2.5 ch.B. 2 ch.C. 4 ch.D. 3 ch.


One of the following is a possible cause for a slow drift of frequency in a self-exited transmitter oscillator circuits resulting to a poor frequency stability.

A. Loose shieldingB. Heating of capacitor in the oscillatorC. Poor soldered connectionsD. Faulty capacitor, resistor, tubes or resistors


A modulation which does not follow the sine wave pattern, it produces undesirable harmonics such as spurious emission

A. 0% modulatedB. Over-modulatedC. UnmodulatedD. 100% modulated

ANSWER KEY

Test Yourself –Exam 01

1. A2. B3. B4. A5. C6. B7. B8. B9. B10. C11. C12. A13. D14. A15. B16. A17. C18. A19. D20. C21. C

22. B23. B24. C25. D26. B27. B28. B29. A30. B31. C32. C33. B34. A35. D36. C37. A38. C39. B40. A41. A42. C43. C44. C45. B46. D47. A48. C49. D50. A51. B52. C53. D54. D55. B56. D57. B58. C59. D60. D61. A62. D63. A

64. B65. B66. A67. C68. A69. A70. D71. B72. A73. B74. A75. C76. C77. C78. B79. C80. C81. C82. D83. D84. C85. A86. D87. D88. B89. D90. D91. D92. C93. C94. C95. B96. B97. A98. A99. C100. D


1. C2. B3. D4. D5. A6. C7. A8. C9. A10. B11. A12. A13. B14. A15. C16. C17. A18. C19. C20. D21. D22. A23. B24. A25. C26. B27. C28. C29. A30. B31. D32. C33. D34. A35. D36. B37. B38. D39. C40. C41. C42. D

43. B44. B45. A46. A47. D48. D49. B50. B51. C52. C53. D54. D55. D56. B57. B58. D59. B60. C61. B62. C63. D64. D65. C66. D67. D68. A69. A70. A71. B72. D73. B74. C75. C76. C77. B78. D79. B80. C81. B82. D83. D84. B

85. A86. C87. B88. C89. C90. C91. C92. D93. A94. B95. C96. C97. D98. B99. D100. D


1. A2. B3. B4. B5. D6. D7. A8. B9. B10. B11. C12. A13. D14. B15. D16. B17. D18. B19. C20. C

21. B22. A23. D24. B25. C26. D27. C28. C29. B30. B31. D32. A33. B34. C35. B36. C37. C38. D39. A40. B41. D42. A43. B44. C45. C46. A47. C48. A49. A50. A51. D52. B53. D54. D55. B56. A57. D58. C59. C60. D61. B62. A

63. C64. B65. B66. C67. B68. B69. D70. A71. C72. A73. D74. D75. A76. A77. C78. A79. C80. D81. A82. A83. B84. C85. C86. D87. B88. C89. C90. B91. D92. B93. D94. B95. D96. B97. B98. A99. A100. D


1. C2. C3. B4. D5. C6. B7. D8. B9. C10. C11. A12. C13. B14. A15. A16. D17. B18. B19. C20. C21. C22. D23. A24. A25. A26. D27. D28. C29. B30. C31. C32. C33. A34. A35. D36. B37. C38. C39. C40. B

41. D42. C43. D44. B45. C46. B47. C48. C49. A50. B51. C52. B53. A54. B55. D56. A57. A58. B59. A60. C61. D62. D63. A64. C65. C66. A67. C68. A69. D70. B71. D72. A73. A74. C75. D76. D77. B78. D79. B80. A81. D82. B

83. B84. B85. C86. B87. B88. B89. B90. D91. A92. A93. A94. D95. E96. C97. A98. C99. B100. A


1. C2. A3. C4. A5. C6. B7. A8. A9. B10. A11. D12. B13. B14. B15. A16. C17. A18. C

19. B20. C21. D22. C23. C24. A25. A26. C27. A28. B29. A30. A31. B32. B33. D34. A35. B36. C37. D38. D39. B40. B41. D42. B43. D44. A45. B46. C47. B48. D49. B50. D51. D52. D53. C54. D55. C56. A57. A58. A59. B60. C

61. A62. C63. C64. B65. D66. B67. A68. C69. B70. B71. D72. B73. D74. C75. A76. C77. D78. B79. A80. D81. D82. B83. A84. A85. C86. C87. A88. C89. D90. C91. B92. D93. C94. B95. C96. D97. B98. B99. B100. C


1. D2. D3. B4. D5. D6. D7. B8. B9. B10. C11. C12. B13. C14. C15. D16. B17. B18. B19. B20. C21. D22. B23. B24. B25. B26. B27. D28. C29. D30. B31. D32. B33. C34. C35. D36. B37. B38. C

39. D40. C41. A42. B43. A44. C45. C46. D47. B48. C49. B50. B51. B52. C53. B54. D55. D56. B57. D58. D59. C60. D61. D62. D63. B64. D65. D66. D67. D68. A69. B70. C71. B72. B73. B74. D75. B76. D77. C78. C79. B80. B

81. C82. C83. C84. C85. B86. D87. C88. D89. D90. B91. C92. D93. C94. B95. D96. D97. B98. D99. B100. B

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