Q1-50

. Typical speech power A. 10 to 1000 W B. 100 to 1000 mW C. 10 to 1000 nW D. 100 to 1000 pW2. The maximum intelligibility for voice frequency is located between A. 250 and 500 Hz B. 1000 and 3000 Hz C. 500 and 1000 Hz D. 3000 and 5000 Hz3. The maximum voice energy is located between A. 250 and 500 Hz B. 1000 and 3000 Hz C. 500 and 1000 Hz D. 3000 and 5000 Hz4. A device used to measure speech volume. A. speech meter B. volume meter C. volume unit meter D. speedometer5. By definition, for a sine wave A. 0 dBm = 0 V.U. B. 0 dBW = 0 V.U. C. 0 dBa = 0 V.U. D. 0 dBf = 0 V.U.6. Presently, this is the standard frequency bandwidth for voice transmission. A. 0 to 4000 Hz B. 100 to 3400 Hz C. 300 to 3400 Hz D. 300 to 3000 Hz7. Which of the following is commonly used wire for subscriber loopdesign? A. AWG # 19 B. AWG # 18 C. AWG # 30 D. AWG # 338. The resistance limit for No. 2 Crossbar Exchange (US) is A. 1300 B. 2000 C. 1250 D. 1200 9. AWG # 26 has a typical loss of A. 0.21 dB/1000 ft. B. 0.32 dB/1000 ft. C. 0.41 dB/1000 ft. D. 0.51 dB/1000 ft.10. What is thestandard voice channel spacing? A. 44 MHz B. 40 kHz C. 4 kHz D. 40 MHz11. Which tester is used to measure SWR? A. Multimeter B. Oscilloscope C. Spectrum analyzer D. Reflectometer12. What is singing? A. The result of intermodulating two or more signals of different frequencies to produce a tone having a frequency equal to the sum of the frequencies of the signals intermodulated. B. The result of intermodulating two or more signals of different frequencies to produce a tone having a frequency higher than that of the signal having the highest frequency. C. An undesired self-sustained oscillation in a system, generally caused by excessive positive feedback. D. An art or form of entertainment that can make one rich.13. Which stage increases the selectivity of the circuit in an AM receiver? A. Detector B. IF stage C. Modulator D. Mixer14. The ________ of radio receiver amplify weak signal and produce a desirable intelligence at the output speaker. A. sensitivity B. selectivity C. reliability D. fidelity15. Full-duplex transmission means A. One-way transmission B. 24-hour transmission C. Broadcast transmission D. Two-way simultaneous transmission16. What is a multidrop line? A. A piece of wire with a thick insulating material that serves to protect the conductive materials from damage in the event the wire is dropped. B. A line designed to withstand high pressure. C. A line or circuit interconnecting several situations. D. A bus line17. A passive _________ is anelectronicdevice which reduces signal strength by a specified amount in dB. A. Splitter B. Filter C. Trimmer D. Attenuator18. The signal quality of the calls is constantly monitored by the base station, when the quality of the calls drops below a certain specified level. The base request the MTSO to try and find a better cell site. A. Hand-off B. Cell splitting C. Roaming D. Frequency reuse19. A digital identification associated with a cellular system. A. SAT B. SID C. ESN D. MIN20. How many seconds does facsimile transmit a stranded page? A. 5 B. 10 C. 20 D. 2521. A kind of recording used in facsimile. A. Electrolytic recording B. Electrothermal recording C. Electropercussive recording D. Electrostatic recording22. A type of distortion a facsimile produce when it becomes out of synchronization? A. Pincushion B. Barrel C. Skewing D. Fattening23. What is an acoustic coupler? A. A device that radiates audible signals via a transmitting antenna B. A device thatconvertselectric signals intoaudiosignals, enabling data to be transmitted over thepublictelephone network via a conventional telephone handset C. A device that receives audible signals and retransmits them at VHF frequencies D. A transducer24. Cause a herringbone pattern in facsimile A. Single-frequency interference B. Crosstalk C. Phase jitter D. Noise25. The _______ in an FM receiver causes a stronger signal to dominate over a weaker signal on the same frequency. A. Capture effect B. Flywheel effect C. Hall effect D. Skin effect26. A device thatconvertsa 2-wire circuit to a 4-wire circuit. A. RS-232 interface B. Hybrid circuit C. Balun D. Stub27. ______ theory is deciding between a set of hypothesis when given a collection of imperfect measurements. A. Estimation B. Traffic C. Decision D. Nyquist28. ______ of a data reduction says that when reducing a set of data into the form of an underlying mode, one should be maximally non-committal with respect to missing data. A. Jaynes maximum entropy principle B. Kullback principle of minimum discrimination C. Minimum discrimination\ D. Maximum entropy29. _______ is selecting the best value of a parameter from a continuum of possible values when gives a collection if imperfect measurements A. Estimation B. Traffic C. Decision D. Nyquist30. Combination of madulator, channel, and detector. A. Transceiver B. Transponder C. T/R channel D. Discrete channel31. What is the frequency band of DECT? A. 1.88 1.90 GHz B. 1.68 1.70 GHz C. 1.48 1.50 GHz D. 1.28 1.30 GHz32. How many simultaneous calls does each DECT system can support? A. 96 B. 12 C. 24 D. 4933. How many simultaneous calls does a DECT radio transceiver can assess at any given time? A. 120 B. 240 C. 480 D. 96034. The AGC voltage of a radio receiver is always _______. A. Present before adjustments can be made B. DC, but may have either polarity positive DC C. Positive DC D. Negative35. What is a concentrator? A. A system that improves the signal-to-noise ratio by compressing the volume range of a signal. B. A device that varies the characteristics of a carrier signal in accordance with the waveform of a modulating signal which contains useful information C. A switching system that lets a large number of telephone or data processing subscribers use a lesser number of transmission lines or a narrow bandwidth D. Equipment in the central office.36. If you find that an SAW filter output is 6 dB down from the input of a receiver during test, ______ A. This is normal. B. The device if faulty C. The receiver is improperly terminated D. The filter is not resonating37. A triple conversion superheterodyne receiver, diode mixer stages are A. Operated in the linear region B. Operated in the nonlinear region C. Operated as Class-A amplifiers D. Operated as Class-B amplifiers38. What is a leased line? A. A piece of wire used in a local area network in one building B. A piece of wire connecting a telephone set to a PABX C. A temporary connection of one computer to a mainframe via a modern and a telephone line D. A permanent circuit for a private use within a communication network39. If two FM signals of different strengths are received on the same frequency A. One steady heterodyne will appear in the AM output B. Both will appear in the AF output C. Only the stronger will appear in the AF output D. Neither signal will be intelligence unless the weaker signal is at least 10 times40. Cellular mobile system was first operated in A. 1979 B. 1981 C. 1983 D. 198541. TACS is a cellular system with ______ channels. A. 666 B. 1000 C. 832 D. 20042. Supervisory Audio Tone (SAT) has _______ frequency. A. 5960 Hz B. 6000 Hz C. 6040 Hz D. 1004 z43. What is the number of channels of a cellular system with an allocated spectrum of 25 MHz and with a channel of 30 kHz bandwidth? A. 833 B. 240 C. 1000 D. 66644. GSSM uses what digital modulation technique? A. QAM B. GFSK C. BPSK D. GMSK45. What is the power output of Personal Communication System (PCS)? A. 10 mW B. 75 mW C. 150 mW D. 10 W46. RG-B8 cable has a loss of about ______ dB at cellular frequencies up to 15 ft. length. A. 2 B. 1 C. 4 D. 347. The signals designed to keep the receivers and transmitters aligned. A. Carrier frequencies B. Pilot carrier signals C. Synchronizing signals D. Reference signals48. If the spacing of a two-wire open air transmission line is 12 inches and the conductor diameter is 0.25 inch, the characteristic impedance is A. 547 B. 357 C. 273 D. 300 49. The impedance of the quarterwave transformer used to match a 600 line to a 300 load is A. 382 B. 424 C. 565 D. 712 50. When a line and a load are match the reflection coefficient is A. Unity B. Zero C. Positive infinity D. Negative infinity

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Answers10 to 1000 W2. 1000 and 3000 Hz3. 250 and 500 Hz4. volume unit meter5. 0 dBm = 0 V.U.6. 300 to 3400 Hz7. AWG # 198. 1300 9. 0.51 dB/1000 ft.10. 4 kHz11. Reflectometer12. An undesired self-sustained oscillation in a system, generally caused by excessive positive feedback.13. IF stage14. sensitivity15. Two-way simultaneous transmission16. A line or circuit interconnecting several situations.17. Attenuator18. Roaming19. MIN20. 2521. Electrolytic recording22. Skewing23. A device that converts electric signals into audio signals, enabling data to be transmitted over the public telephone network via a conventional telephone handset24. Crosstalk25. Capture effect26. Hybrid circuit27. Decision28. Jaynes maximum entropy principle29. Estimation30. Discrete channel31. 1.88 1.90 GHz32. 1233. 12034. DC, but may have either polarity positive DC35. A switching system that lets a large number of telephone or dataprocessingsubscribers use a lesser number of transmission lines or a narrow bandwidth36. This is normal.37. Operated in the nonlinear region38. A permanent circuit for a private use within a communication network39. Only the stronger will appear in the AF output40. 198341. 100042. 6000 Hz43. 83344. GFSK45. 10 mW46. 347. Pilot carrier signals48. 547 49. 424 50. Zero

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Q51-100hen line is terminated in an open circuit load, the reflection coefficient is A. Unity B. Zero C. Positive infinity D. Negative infinity52. A 300 ohms line is terminated in a resistance load of 200 ohms, the VSWR is A. 0.65 B. 1.5 C. Unity D. Zero53. If the reflection coefficient is 0.5, the standing wave ratio is A. 0.33 B. Unity C. 3 D. Zero54. To least the fault of the given line, a signal is fed to the line, 30 s later the signal returned. What is the distance of the fault? A. 9000 m B. 300 m C. 100 m D. 4500 m55. The telephone set is powered by the central office on the ring side at A. 42 to 52 Vdc B. 42 to -52 Vdc C. 24 to 64 Vdc D. 24 to 64 Vdc56. The telephone voice band frequency is from A. 300 to 4 kHz B. 400 to 3400 Hz C. 300 to 3400 Hz D. 400 to 4 kHz57. Which of the following wire is used to transmit the signal? A. Black B. Yellow C. Red D. Green58. The corresponding frequency for digit 7 in the touch tone telephone is A. 770 & 1477 Hz B. 852 & 1209 Hz C. 852 & 1336 Hz D. 770 & 1336 Hz59. The physical connection between the telephone set and the switching equipment is called the A. Trunk line B. Link C. Subscriber loop D. Leased line60. What is the local loop of a telephone system? A. It is a two-wire or four-wire communication circuit between the customers premise and the central office B. It is a group of wires connecting a telephone set to a modern C. It is a four-wire circuit connecting a facsimile machine to a computer D. It is asinglepiece of wire connecting the subscribers telephone set to another set in an adjacent room.61. Which of the ff. equipment is used in long loop design? A. Dial long lines B. Voice repeater C. Loop range extender D. All of the above62. What is a two-wire circuit? A. A circuit usually in the subscriber loop, between the telephone set and the local central office. B. A circuit having only two terminals, both terminals having the same instantaneous voltage. C. A circuit with one input terminal, one output terminal, and a common ground. D. A circuit consisting of two transmission lines.63. 1 mW is equal to A. 90 dBm B. 0 dBm C. -30 dBm D. 120 dBm64. Which of the following responds to the request of a subscriber by sending a dial tone? A. Line finder B. First selector C. Connector D. Line equipment65. The other name of Class 2 office in the North American Switching Plan. A. Primary center B. Section C. Regional center D. Toll points66. A cell in the cellular telephone system means A. A power source B. Small area C. Large area D. Service area67. What is the linking point between cell phone and regular telephone? A. Base station B. Control office C. C.O. D. MTSO68. What is the typical power output of a cellular phone? A. 5 W B. 10 W C. 1 W D. 3 W69. When asinglecell is divided into smaller cells that process is called A. Cell splitting B. Cell division C. Reuse D. Cell sharing70. The first cell shape is a square A. Square B. Circle C. Rectangle D. Triangle71. In order to provide 100% coverage without overlap, cellular telephone system can use A. Hexagon cell shape B. Triangle C. Rectangular D. All of the above72. What is the beamwidth of the reflector of the receiving antenna in the base station A. 20 degrees B. 30 degrees C. 50 degrees D. 60 degrees73. A cellular phone operates on A. Half duplex B. Full duplex C. Echoplex D. Lincomplex74. Cellular phones transmit in the band from A. 825 to 845 MHz B. 835 to 855 MHz C. 825 to 855 MHz D. 825 to 865 MHz75. Cell phone receives in the band from A. 860 to 880 MHz B. 870 to 890 MHz C. 870 to 880 MHz D. 860 to 890 MHz76. What is the frequency separation between the transmit and the receive channels? A. 30 MHz B. 45 MHz C. 55 MHz D. 40 MHz77. Forchannel 1, transmit/receive frequency is A. 825.030/870.030 MHz B. 835.03/880.03 MHz C. 825.015/870.015 MHz D. 825.15/870.15 MHz78. The number of transmit/receive channels in the cellular system is A. 625 B. 645 C. 655 D. 66679. The transmission range of cellular telephony is generally about A. 80 km B. 65 km C. 160 km D. 16 km80. One of the following is not an advantage of a cellular telephone system A. Privacy B. Large service area C. No interference D. Mobility81. When the message is transferred from one cell site transmitter to another cell site transmitter as the caller crosses a boundary __________ process takes place. A. Shifting B. Hand off C. Give off D. Turn over82. What is the sensitivity of a cellular receiver? A. 20 dB B. 40 dB C. 50 dB D. 60 dB83. What is the frequency deviation of the cellular telephone system? A. 15 kHz B. 30 kHz C. 12 kHz D. 75 kHz84. Hailing channel is otherwise known as A. Conversation channel B. Calling channel C. Signaling channel D. Remote channel85. What is an Erlang? A. It is a unit of magnetic field intensity measured around a conductor B. It is the number of erroneous bits received per unit of time C. It a unit of electrical energy radiated in space. D. It is equal to the number of simultaneous calls originated during a specific hourly period.86. All of the cell base stations are linked together by _______ which serves as the central office and management node for the group. A. MTS B. IMTS C. MSTO D. MTSO87. Provides interface between the mobile telephone switching office and the mobile units. A. Database B. Cell site C. Terrestrial link D. Radio transmitter88. A phone call over the cellular network actually requires A. Simplex channels B. Half duplex channels C. Full duplex channels D. Full/full duplex89. Amethodof expressing the amplitudes of complex non-periodic signals such as speech. A. Volume B. Pitch C. Frequency D. Wavelength90. _______ is signal returned to the talker after one or more round trips between the talker and the listener. A. Singing B. Echo C. Jitter D. Crosstalk91. ______ is a voice operated device that inserts a high loss in the opposite direction of transmission of the talking party. A. Hybrid B. 2-wire circuit C. Echo suppressor D. VNL92. _____ is picking up of the same station at two nearby points on the receiver dial. A. Double spotting B. Hot shot C. Image frequency D. Bail shot93. When one channel picks up the signal carried by another channel. A. Echo B. Crosstalk C. Party line D. Crosslink94. What type of connector arrangement wherein a customer may move to another location and still retain the sametelephone number. A. TPL B. Bridge C. TPS D. Party line95. It is an advantage of sidetone. A. Transmission efficiency is increased B. Speaker increase his voice resulting in a strengthened signal C. No dissipation of energy in the balancing network D. Assures the customer that the telephone is working96. Radio communications between points using asingleshare frequency. A. Simplex B. Full duplex C. Half-duplex D. Full/full duplex97. The transmission of information from multiple sources occurring on the same facility but not as the same time. A. FDM B. TDM C. WDM D. CDM98. When human voice and music are transmitted, the type of communication employed is known as A. Raditechnology B. Audio frequency C. Wired audio D. Radiotelephony99. Printed documents to be transmitted by fax are converted into baseband electric signal by the process of A. Copying B. Scanning C. Modulation D. Light variation100. What is the most commonly used light sensor in a modern fax machine? A. Phototube B. Phototransistor C. Liquid-crystal display D. Charge couple device

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Answers:51. Unity52. 1.553. C. 354. 4500 m55. 42 to -52 Vdc56. 300 to 3400 Hz57. Green58. 852 & 1209 Hz59. Subscriber loop60. It is a two-wire or four-wire communication circuit between the customers premise and the central office61. All of the above62. A circuit usually in the subscriber loop, between the telephone set and the local central office.63. 90 dBm64. First selector65. Section66. Small area67. MTSO68. 3 W69. Cell splitting70. Circle71. All of the above72. 60 degrees73. Full duplex74. 825 to 845 MHz75. 870 to 890 MHz76. 45 MHz77. 825.015/870.015 MHz78. 66679. 80 km80. Large service area81. Hand off82. 50 dB83. 12 kHz84. Calling channel85. It is equal to the number of simultaneous calls originated during a specific hourly period.86. MTSO87. Cell site88. Full duplex channels89. Volume90. Echo91. Echo suppressor92. Double spotting93. Crosstalk94. TPS95. Assures the customer that the telephone is working96. Half-duplex97. TDM98. Radiotelephony99. Scanning100. Charge couple device

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