1. Amateur Radio Good Operating Practices

2. Class Schedule Topics Topics √ Radio Spectrum, Licensing and Methods (09/22) T1,T2,T7A/B √ Radio Phenomena (09/29) T3, √ Station Licensee and Control Op Duties (10/06) T4,T5 ► Good Operating Practices, Special Ops (10/13) T6,T9 u T8A – Basic Station Apparatus –Basic Electronics (10/20) T7 –Good Engineering Practices (10/27) T8 –Electrical, Antennas and RF Safety (11/03) T0 –Review/Practice (11/10) All Home Study Home Study –Reading Assignments – Section 7 basic Electronics –Home Work – Test Review –Morse Code Test Test –Nov 17 th

3. T6 -- Good Operating Practices [3 Exam Questions -- 3 Groups] T8 – Good Engineering Practices [6 Exam Questions – 6 Groups] –T6ACalling another station; Calling CQ; Typical amateur service radio contacts; Courtesy and respect for others; Popular Q-signals; Signal reception reports; Phonetic alphabet for voice operations. –T6BOccupied bandwidth for emission types; Mandated and voluntary band plans; CW operation. –T6CTVI and RFI reduction and elimination, Band/Low/High pass filter, Out of band harmonic Signals, Spurious Emissions, Telephone Interference, Shielding, Receiver Overload. –T8ABasic amateur station apparatus: Choice of apparatus for desired communications; Setting up a station: construction and modifying amateur station apparatus; Station layout for CW, SSB, FM and Packet and other popular modes.

4. Basic Voice (Phone) Communication Rules Be polite Be polite – Do not interrupt other – Do not hog the channel Listen before you talk Listen before you talk – If someone else is using the frequency, let them have it, move to somewhere else. Keep it simple Keep it simple – Speak Clearly – Do not rush it – Use Term people understand Use the ITU Phonetic Alphabet to spell thing out Use the ITU Phonetic Alphabet to spell thing out Use Common Abbreviations and TLA (Three Letter Acronyms) Use Common Abbreviations and TLA (Three Letter Acronyms) Use the right side and for voice SSB Use the right side and for voice SSB – >14MHz - Use Upper Side Band

5. ITU Phonetic Alphabet Agreed upon words to represent the letters of the “roman alphabet”. The boldfaced syllables are emphasized. The pronunciations shown in this table were designed for those who speak any of the international languages. The pronunciations given for “Oscar”, “Papa” and “Victor” may seem awkward to English-speaking people in the US.

6. Common Abbreviation You need to know CQ – Call Any Station CQ – Call Any Station RST – Readability, Signal Strength, Tone RST – Readability, Signal Strength, Tone QSO – A communication QSO – A communication QSL – Acknowledge Reception QSL – Acknowledge Reception DX – Distance, foreign country DX – Distance, foreign country 73 - Best Regards 73 - Best Regards DE – From, this is DE – From, this is PTT – Push To Talk PTT – Push To Talk VOX – Voice Activated Switch (x) VOX – Voice Activated Switch (x)

7. Starting a Conversation (QSO) Open Call – I will talk to anybody (CQ) Open Call – I will talk to anybody (CQ) –Listen –Check – Is this frequency in use? This is KD7PSV –Place the call u CQ CQ calling CQ. This is KD7PSV, Kilo Delta Seven Papa Sierra Victor, KD7PSV calling CQ and standing by. –To Answer u KD7PSV, this is N7SS, November 7 Sierra Sierra, N7SS over Direct Call – I know who I want to talk to Direct Call – I know who I want to talk to –Listen –Check – Is this frequency in use? This is KD7PSV –Place the call u KD7PSV calling N7SS, Kilo Delta Seven Papa Sierra Victor calling November Seven Sierra Sierra, KD7PSV calling N7SS –Answering a call u KD7PSV this is N7SS, over Ending the Conversation Ending the Conversation –This is KD7PSV clear –This is N7SS clear

8. Some HAMS collect QSL Cards

9. The RST System

10. Amateur Q Signals

11. Common required Bandwidth CW – 5-10Hz CW – 5-10Hz Phone/ Voice Phone/ Voice –SSB - 2-3KHz –AM – 4-6KHz –FM – 10-20KHz Digital Digital –PSK31 – 31 Hz –RTTY – 500 Hz Slow Scan TV – 3KHz Slow Scan TV – 3KHz Fast Scan TV – 6Mhz Fast Scan TV – 6Mhz

12. S - Meters The S - meter gives a relative signal strength reading of a received signal. (Scale 0-9) No manufacturer claims their S - meters are calibrated.

13. Low Pass, High Pass Filters High Pass Frequency Low Pass Frequency

14. Band Pass Filter Band Pass High Frequency Low Frequency

15. Figuring out which filter you may need Determine the two bands that are interfering, and draw a line between them Determine the two bands that are interfering, and draw a line between them Determine which band to keep, or equipment to attach Determine which band to keep, or equipment to attach –Left low, Right high HFTV

16. T6A01What is the advantage of using the International Telecommunication Union (ITU) phonetic alphabet when identifying your station? –A.The words are internationally recognized substitutes for letters –B.There is no advantage –C.The words have been chosen to represent Amateur Radio terms –D.It preserves traditions begun in the early days of Amateur Radio

17. T6A01What is the advantage of using the International Telecommunication Union (ITU) phonetic alphabet when identifying your station? A.The words are internationally recognized substitutes for letters A.The words are internationally recognized substitutes for letters –B.There is no advantage –C.The words have been chosen to represent Amateur Radio terms –D.It preserves traditions begun in the early days of Amateur Radio

18. T6A02What is one reason to avoid using "cute" phrases or word combinations to identify your station? –A.They are not easily understood by non- English-speaking amateurs –B.They might offend English-speaking amateurs –C.They do not meet FCC identification requirements –D.They might be interpreted as codes or ciphers intended to obscure the meaning of your identification

19. T6A02What is one reason to avoid using "cute" phrases or word combinations to identify your station? A.They are not easily understood by non- English-speaking amateurs A.They are not easily understood by non- English-speaking amateurs –B.They might offend English-speaking amateurs –C.They do not meet FCC identification requirements –D.They might be interpreted as codes or ciphers intended to obscure the meaning of your identification

20. T6A03What should you do before you transmit on any frequency? –A.Listen to make sure others are not using the frequency –B.Listen to make sure that someone will be able to hear you –C.Check your antenna for resonance at the selected frequency –D.Make sure the SWR on your antenna feed line is high enough

21. T6A03What should you do before you transmit on any frequency? A.Listen to make sure others are not using the frequency A.Listen to make sure others are not using the frequency –B.Listen to make sure that someone will be able to hear you –C.Check your antenna for resonance at the selected frequency –D.Make sure the SWR on your antenna feed line is high enough

22. T6A04How do you call another station on a repeater if you know the station's call sign? –A.Say "break, break 79," then say the station's call sign –B.Say the station's call sign, then identify your own station –C.Say "CQ" three times, then say the station's call sign –D.Wait for the station to call "CQ," then answer it

23. T6A04How do you call another station on a repeater if you know the station's call sign? –A.Say "break, break 79," then say the station's call sign B.Say the station's call sign, then identify your own station B.Say the station's call sign, then identify your own station –C.Say "CQ" three times, then say the station's call sign –D.Wait for the station to call "CQ," then answer it

24. T6A05What does RST mean in a signal report? –A.Recovery, signal strength, tempo –B.Recovery, signal speed, tone –C.Readability, signal speed, tempo –D.Readability, signal strength, tone

25. T6A05What does RST mean in a signal report? –A.Recovery, signal strength, tempo –B.Recovery, signal speed, tone –C.Readability, signal speed, tempo D.Readability, signal strength, tone D.Readability, signal strength, tone

26. T6A06What is the meaning of: "Your signal report is five nine plus 20 dB..."? –A.Your signal strength has increased by a factor of 100 –B.Repeat your transmission on a frequency 20 kHz higher –C.The bandwidth of your signal is 20 decibels above linearity –D.A relative signal-strength meter reading is 20 decibels greater than strength 9

27. T6A06What is the meaning of: "Your signal report is five nine plus 20 dB..."? –A.Your signal strength has increased by a factor of 100 –B.Repeat your transmission on a frequency 20 kHz higher –C.The bandwidth of your signal is 20 decibels above linearity D.A relative signal-strength meter reading is 20 decibels greater than strength 9 D.A relative signal-strength meter reading is 20 decibels greater than strength 9

28. T6A07What is the meaning of the procedural signal "CQ"? –A.Call on the quarter hour –B.New antenna is being tested (no station should answer) –C.Only the called station should transmit –D.Calling any station

29. T6A07What is the meaning of the procedural signal "CQ"? –A.Call on the quarter hour –B.New antenna is being tested (no station should answer) –C.Only the called station should transmit D.Calling any station D.Calling any station

30. T6A08What is a QSL card in the amateur service? –A.A letter or postcard from an amateur pen pal –B.A Notice of Violation from the FCC –C.A written acknowledgment of communications between two amateurs –D.A postcard reminding you when your license will expire

31. T6A08What is a QSL card in the amateur service? –A.A letter or postcard from an amateur pen pal –B.A Notice of Violation from the FCC C.A written acknowledgment of communications between two amateurs C.A written acknowledgment of communications between two amateurs –D.A postcard reminding you when your license will expire

32. T6A09What is the correct way to call CQ when using voice? –A.Say "CQ" once, followed by "this is," followed by your call sign spoken three times –B.Say "CQ" at least five times, followed by "this is," followed by your call sign spoken once –C.Say "CQ" three times, followed by "this is," followed by your call sign spoken three times –D.Say "CQ" at least ten times, followed by "this is," followed by your call sign spoken once

33. T6A09What is the correct way to call CQ when using voice? –A.Say "CQ" once, followed by "this is," followed by your call sign spoken three times –B.Say "CQ" at least five times, followed by "this is," followed by your call sign spoken once C.Say "CQ" three times, followed by "this is," followed by your call sign spoken three times C.Say "CQ" three times, followed by "this is," followed by your call sign spoken three times –D.Say "CQ" at least ten times, followed by "this is," followed by your call sign spoken once

34. T6A10How should you answer a voice CQ call? –A.Say the other station's call sign at least ten times, followed by "this is," then your call sign at least twice –B.Say the other station's call sign at least five times phonetically, followed by "this is," then your call sign at least once –C.Say the other station's call sign at least three times, followed by "this is," then your call sign at least five times phonetically –D.Say the other station's call sign once, followed by "this is," then your call sign given phonetically

35. T6A10How should you answer a voice CQ call? –A.Say the other station's call sign at least ten times, followed by "this is," then your call sign at least twice –B.Say the other station's call sign at least five times phonetically, followed by "this is," then your call sign at least once –C.Say the other station's call sign at least three times, followed by "this is," then your call sign at least five times phonetically D.Say the other station's call sign once, followed by "this is," then your call sign given phonetically D.Say the other station's call sign once, followed by "this is," then your call sign given phonetically

36. T6A11What is the meaning of: "Your signal is full quieting..."? –A.Your signal is strong enough to overcome all receiver noise –B.Your signal has no spurious sounds –C.Your signal is not strong enough to be received –D.Your signal is being received, but no audio is being heard

37. T6A11What is the meaning of: "Your signal is full quieting..."? A.Your signal is strong enough to overcome all receiver noise A.Your signal is strong enough to overcome all receiver noise –B.Your signal has no spurious sounds –C.Your signal is not strong enough to be received –D.Your signal is being received, but no audio is being heard

38. T6A12What is meant by the term "DX"? –A.Best regards –B.Distant station –C.Calling any station –D.Go ahead

39. T6A12What is meant by the term "DX"? –A.Best regards B.Distant station B.Distant station –C.Calling any station –D.Go ahead

40. T6A13What is the meaning of the term "73"? –A.Long distance –B.Best regards –C.Love and kisses –D.Go ahead

41. T6A13What is the meaning of the term "73"? –A.Long distance B.Best regards B.Best regards –C.Love and kisses –D.Go ahead

42. T6B01Which list of emission types is in order from the narrowest bandwidth to the widest bandwidth? –A.RTTY, CW, SSB voice, FM voice –B.CW, FM voice, RTTY, SSB voice –C.CW, RTTY, SSB voice, FM voice –D.CW, SSB voice, RTTY, FM voice

43. T6B01Which list of emission types is in order from the narrowest bandwidth to the widest bandwidth? –A.RTTY, CW, SSB voice, FM voice –B.CW, FM voice, RTTY, SSB voice C.CW, RTTY, SSB voice, FM voice C.CW, RTTY, SSB voice, FM voice –D.CW, SSB voice, RTTY, FM voice

44. T6B02What is the usual bandwidth of a single-sideband amateur signal? –A.1 kHz –B.2 kHz –C.Between 3 and 6 kHz –D.Between 2 and 3 kHz

45. T6B02What is the usual bandwidth of a single-sideband amateur signal? –A.1 kHz –B.2 kHz –C.Between 3 and 6 kHz D.Between 2 and 3 kHz D.Between 2 and 3 kHz

46. T6B03What is the usual bandwidth of a frequency-modulated amateur signal? –A.Less than 5 kHz –B.Between 5 and 10 kHz –C.Between 10 and 20 kHz –D.Greater than 20 kHz

47. T6B03What is the usual bandwidth of a frequency-modulated amateur signal? –A.Less than 5 kHz –B.Between 5 and 10 kHz C.Between 10 and 20 kHz C.Between 10 and 20 kHz –D.Greater than 20 kHz

48. Amateur Television Signal A 6 MHz ATV video channel with the video carrier 1.25 MHz up from the lower edge. The color subcarrier is at 3.58 MHz and the sound subcarrier at 4.5 MHz above the video carrier. The Luminance, Chrominance and Audio carriers are visible in the spectrum plot at left

49. T6B04What is the usual bandwidth of a UHF amateur fast-scan television signal? –A.More than 6 MHz –B.About 6 MHz –C.About 3 MHz –D.About 1 MHz

50. T6B04What is the usual bandwidth of a UHF amateur fast-scan television signal? –A.More than 6 MHz B.About 6 MHz B.About 6 MHz –C.About 3 MHz –D.About 1 MHz

51. T6B05What name is given to an amateur radio station that is used to connect other amateur stations with the Internet? –A.A gateway –B.A repeater –C.A digipeater –D.FCC regulations prohibit such a station

52. T6B05What name is given to an amateur radio station that is used to connect other amateur stations with the Internet? A.A gateway A.A gateway –B.A repeater –C.A digipeater –D.FCC regulations prohibit such a station

53. T6B06What is a band plan? –A.A voluntary guideline beyond the divisions established by the FCC for using different operating modes within an amateur band –B.A guideline from the FCC for making amateur frequency band allocations –C.A plan of operating schedules within an amateur band published by the FCC –D.A plan devised by a club to best use a frequency band during a contest

54. T6B06What is a band plan? A.A voluntary guideline beyond the divisions established by the FCC for using different operating modes within an amateur band A.A voluntary guideline beyond the divisions established by the FCC for using different operating modes within an amateur band –B.A guideline from the FCC for making amateur frequency band allocations –C.A plan of operating schedules within an amateur band published by the FCC –D.A plan devised by a club to best use a frequency band during a contest

55. T6B07At what speed should a Morse code CQ call be transmitted? –A.Only speeds below five WPM –B.The highest speed your keyer will operate –C.Any speed at which you can reliably receive –D.The highest speed at which you can control the keyer

56. T6B07At what speed should a Morse code CQ call be transmitted? –A.Only speeds below five WPM –B.The highest speed your keyer will operate C.Any speed at which you can reliably receive C.Any speed at which you can reliably receive –D.The highest speed at which you can control the keyer

57. T6B08What is the meaning of the procedural signal "DE"? –A."From" or "this is," as in "W0AIH DE KA9FOX" –B."Directional Emissions" from your antenna –C."Received all correctly" –D."Calling any station"

58. T6B08What is the meaning of the procedural signal "DE"? A."From" or "this is," as in "W0AIH DE KA9FOX" A."From" or "this is," as in "W0AIH DE KA9FOX" –B."Directional Emissions" from your antenna –C."Received all correctly" –D."Calling any station"

59. T6B09What is a good way to call CQ when using Morse code? –A.Send the letters "CQ" three times, followed by "DE," followed by your call sign sent once –B.Send the letters "CQ" three times, followed by "DE," followed by your call sign sent three times –C.Send the letters "CQ" ten times, followed by "DE," followed by your call sign sent twice –D.Send the letters "CQ" over and over until a station answers

60. T6B09What is a good way to call CQ when using Morse code? –A.Send the letters "CQ" three times, followed by "DE," followed by your call sign sent once B.Send the letters "CQ" three times, followed by "DE," followed by your call sign sent three times B.Send the letters "CQ" three times, followed by "DE," followed by your call sign sent three times –C.Send the letters "CQ" ten times, followed by "DE," followed by your call sign sent twice –D.Send the letters "CQ" over and over until a station answers

61. T6B10How should you answer a Morse code CQ call? –A.Send your call sign four times –B.Send the other station's call sign twice, followed by "DE," followed by your call sign twice –C.Send the other station's call sign once, followed by "DE," followed by your call sign four times –D.Send your call sign followed by your name, station location and a signal report

62. T6B10How should you answer a Morse code CQ call? –A.Send your call sign four times B.Send the other station's call sign twice, followed by "DE," followed by your call sign twice B.Send the other station's call sign twice, followed by "DE," followed by your call sign twice –C.Send the other station's call sign once, followed by "DE," followed by your call sign four times –D.Send your call sign followed by your name, station location and a signal report

63. T6B11What is the meaning of the procedural signal "K"? –A."Any station transmit" –B."All received correctly" –C."End of message" –D."Called station only transmit"

64. T6B11What is the meaning of the procedural signal "K"? A."Any station transmit" A."Any station transmit" –B."All received correctly" –C."End of message" –D."Called station only transmit"

65. T6B12What is one meaning of the Q signal "QRS"? –A."Interference from static" –B."Send more slowly" –C."Send RST report" –D."Radio station location is"

66. T6B12What is one meaning of the Q signal "QRS"? –A."Interference from static" B."Send more slowly" B."Send more slowly" –C."Send RST report" –D."Radio station location is"

67. T6C01What is meant by receiver overload? –A.Too much voltage from the power supply –B.Too much current from the power supply –C.Interference caused by strong signals from a nearby source –D.Interference caused by turning the volume up too high

68. T6C01What is meant by receiver overload? –A.Too much voltage from the power supply –B.Too much current from the power supply C.Interference caused by strong signals from a nearby source C.Interference caused by strong signals from a nearby source –D.Interference caused by turning the volume up too high

69. Low Pass Filter A low-pass filter goes between your transmitter and antenna. It removes harmonic radiation from your signals. It will pass the low frequency (HF) ham bands while blocking their harmonics (cutoff frequency 50 MHz). Your neighbors’ TV sets will thank you.

70. T6C02What type of filter might be connected to an amateur HF transmitter to cut down on harmonic radiation? –A.A key-click filter –B.A low-pass filter –C.A high-pass filter –D.A CW filter

71. T6C02What type of filter might be connected to an amateur HF transmitter to cut down on harmonic radiation? –A.A key-click filter B.A low-pass filter B.A low-pass filter –C.A high-pass filter –D.A CW filter

72. T6C03What type of filter should be connected to a TV receiver as the first step in trying to prevent RF overload from an amateur HF station transmission? –A.Low-pass –B.High-pass –C.Band pass –D.Notch

73. T6C03What type of filter should be connected to a TV receiver as the first step in trying to prevent RF overload from an amateur HF station transmission? –A.Low-pass B.High-pass B.High-pass –C.Band pass –D.Notch

74. T6C04What effect might a break in a cable television transmission line have on amateur communications? –A.Cable lines are shielded and a break cannot affect amateur communications –B.Harmonic radiation from the TV receiver may cause the amateur transmitter to transmit off- frequency –C.TV interference may result when the amateur station is transmitting, or interference may occur to the amateur receiver –D.The broken cable may pick up very high voltages when the amateur station is transmitting

75. T6C04What effect might a break in a cable television transmission line have on amateur communications? –A.Cable lines are shielded and a break cannot affect amateur communications –B.Harmonic radiation from the TV receiver may cause the amateur transmitter to transmit off- frequency C.TV interference may result when the amateur station is transmitting, or interference may occur to the amateur receiver C.TV interference may result when the amateur station is transmitting, or interference may occur to the amateur receiver –D.The broken cable may pick up very high voltages when the amateur station is transmitting

76. T6C05If you are told that your amateur station is causing television interference, what should you do? –A.First make sure that your station is operating properly, and that it does not cause interference to your own television –B.Immediately turn off your transmitter and contact the nearest FCC office for assistance –C.Connect a high-pass filter to the transmitter output and a low-pass filter to the antenna-input terminals of the television –D.Continue operating normally, because you have no reason to worry about the interference

77. T6C05If you are told that your amateur station is causing television interference, what should you do? A.First make sure that your station is operating properly, and that it does not cause interference to your own television A.First make sure that your station is operating properly, and that it does not cause interference to your own television –B.Immediately turn off your transmitter and contact the nearest FCC office for assistance –C.Connect a high-pass filter to the transmitter output and a low-pass filter to the antenna-input terminals of the television –D.Continue operating normally, because you have no reason to worry about the interference

78. T6C06If harmonic radiation from your transmitter is causing interference to television receivers in your neighborhood, who is responsible for taking care of the interference? –A.The owners of the television receivers are responsible –B.Both you and the owners of the television receivers share the responsibility –C.You alone are responsible, since your transmitter is causing the problem –D.The FCC must decide if you or the owners of the television receivers are responsible

79. T6C06If harmonic radiation from your transmitter is causing interference to television receivers in your neighborhood, who is responsible for taking care of the interference? –A.The owners of the television receivers are responsible –B.Both you and the owners of the television receivers share the responsibility C.You alone are responsible, since your transmitter is causing the problem C.You alone are responsible, since your transmitter is causing the problem –D.The FCC must decide if you or the owners of the television receivers are responsible

80. T6C07If signals from your transmitter are causing front-end overload in your neighbor's television receiver, who is responsible for taking care of the interference? –A.You alone are responsible, since your transmitter is causing the problem –B.Both you and the owner of the television receiver share the responsibility –C.The FCC must decide if you or the owner of the television receiver are responsible –D.The owner of the television receiver is responsible

81. T6C07If signals from your transmitter are causing front-end overload in your neighbor's television receiver, who is responsible for taking care of the interference? –A.You alone are responsible, since your transmitter is causing the problem –B.Both you and the owner of the television receiver share the responsibility –C.The FCC must decide if you or the owner of the television receiver are responsible D.The owner of the television receiver is responsible D.The owner of the television receiver is responsible

82. T6C08What circuit blocks RF energy above and below certain limits? –A.A band-pass filter –B.A high-pass filter –C.An input filter –D.A low-pass filter

83. T6C08What circuit blocks RF energy above and below certain limits? A.A band-pass filter A.A band-pass filter –B.A high-pass filter –C.An input filter –D.A low-pass filter

84. T6C09If someone tells you that signals from your hand-held transceiver are interfering with other signals on a frequency near yours, what may be the cause? –A.You may need a power amplifier for your hand-held –B.Your hand-held may have chirp from weak batteries –C.You may need to turn the volume up on your hand-held –D.Your hand-held may be transmitting spurious emissions

85. T6C09If someone tells you that signals from your hand-held transceiver are interfering with other signals on a frequency near yours, what may be the cause? –A.You may need a power amplifier for your hand-held –B.Your hand-held may have chirp from weak batteries –C.You may need to turn the volume up on your hand-held D.Your hand-held may be transmitting spurious emissions D.Your hand-held may be transmitting spurious emissions

86. T6C10What may happen if an SSB transmitter is operated with the microphone gain set too high? –A.It may cause digital interference to computer equipment –B.It may cause splatter interference to other stations operating near its frequency –C.It may cause atmospheric interference in the air around the antenna –D.It may cause interference to other stations operating on a higher frequency band

87. T6C10What may happen if an SSB transmitter is operated with the microphone gain set too high? –A.It may cause digital interference to computer equipment B.It may cause splatter interference to other stations operating near its frequency B.It may cause splatter interference to other stations operating near its frequency –C.It may cause atmospheric interference in the air around the antenna –D.It may cause interference to other stations operating on a higher frequency band

88. T6C11What may cause a buzzing or hum in the signal of an HF transmitter? –A.Using an antenna that is the wrong length –B.Energy from another transmitter –C.Bad design of the transmitter's RF power output circuit –D.A bad filter capacitor in the transmitter's power supply

89. T6C11What may cause a buzzing or hum in the signal of an HF transmitter? –A.Using an antenna that is the wrong length –B.Energy from another transmitter –C.Bad design of the transmitter's RF power output circuit D.A bad filter capacitor in the transmitter's power supply D.A bad filter capacitor in the transmitter's power supply

90. T6C12(Reference: FCC CIB Telephone Interference Bulletin) What is the major cause of telephone interference? –A.The telephone ringer is inadequate –B.Tropospheric ducting at UHF frequencies –C.The telephone was not equipped with interference protection when it was manufactured. –D.Improper location of the telephone in the home

91. T6C12(Reference: FCC CIB Telephone Interference Bulletin) What is the major cause of telephone interference? –A.The telephone ringer is inadequate –B.Tropospheric ducting at UHF frequencies C.The telephone was not equipped with interference protection when it was manufactured. C.The telephone was not equipped with interference protection when it was manufactured. –D.Improper location of the telephone in the home