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Stuff Every General Class Ham Should Know

Study the FCC General class question pool one card at a time.

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  1. On which HF bands do General licensees have some off-limits portions?
    Show the answer

    80, 40, 20, and 15 meters. Higher license classes keep some slices of 80, 40, 20 and 15 meters for themselves. Generals can use the rest of those bands, plus every other HF band in full.

  2. On which of these bands is voice (phone) operation prohibited?
    Show the answer

    30 meters. The 30 meter band (around 10.1 MHz) allows only CW, RTTY and data modes. Voice and image are not allowed there, for any license class.

  3. What must hams do when the amateur service is a secondary user on a band?
    Show the answer

    Avoid interfering with primary users and accept their interference. Secondary means the other service has first claim. Hams may use the band, but must not cause harmful interference to primary users and must tolerate interference from them.

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  1. On which HF bands do General licensees have some off-limits portions?
  2. On which of these bands is voice (phone) operation prohibited?
  3. What must hams do when the amateur service is a secondary user on a band?
  4. Which part of the 10 meter band is available for repeaters?
  5. How tall can an antenna structure be, away from an airport, before the FAA and FCC must be notified?
  6. How may state and local governments regulate amateur antenna structures?
  7. What is the maximum power for an amateur beacon station?
  8. What is the power limit on 10.140 MHz (30 meters)?
  9. What is the maximum bandwidth for a USB signal on 60 meters?
  10. How does the FCC measure the maximum power an amateur station may use?
  11. How long is a CSCE valid for exam element credit?
  12. What is the minimum age to be an accredited Volunteer Examiner?
  13. When must a Technician waiting on a General upgrade add AG after the call sign?
  14. Which ITU region's frequency allocations apply to hams in North and South America?
  15. Why should you normally avoid transmitting on 14.100, 18.110, 21.150, 24.930 and 28.200 MHz?
  16. Which sideband is most common for voice on 14 MHz and higher?
  17. Why do most hams use lower sideband on 160, 75 and 40 meters?
  18. What is the recommended way to break into a phone contact?
  19. Who has priority access to a frequency, outside of emergencies?
  20. What minimum spacing should CW stations use to avoid interfering with neighbors?
  21. How can you check that a clear-sounding frequency is not in use before calling CQ?
  22. How often may RACES drills be routinely conducted without special authorization?
  23. What speed should you use when answering a CQ in Morse code?
  24. In CW operation, what does "zero beat" mean?
  25. Which prosign marks the end of a formal message in CW?
  26. How do you aim a beam antenna for a long-path contact?
  27. What does QRP operation mean?
  28. What is the most common frequency shift for RTTY on the amateur HF bands?
  29. Which of these is required to operate FT8?
  30. What is good practice when answering an FT8 station calling CQ?
  31. How long does it take solar flare radiation to start affecting radio propagation on Earth?
  32. What is the solar flux index?
  33. What causes HF conditions to vary in a 26 to 28 day cycle?
  34. What does the K-index measure?
  35. What does MUF stand for?
  36. How far can one hop via the F2 region normally travel?
  37. Which ionospheric region is closest to the Earth's surface?
  38. Why is long-distance work on 160, 80, 60 and 40 meters harder in the daytime?
  39. What is NVIS propagation?
  40. What does the notch filter on many HF transceivers do?
  41. Why is automatic level control (ALC) used with an RF power amplifier?
  42. Why do voltmeters have high input impedance?
  43. What might reduce RF interference to audio circuits?
  44. Why shouldn't soldered joints be used in lightning protection ground connections?
  45. What helps reduce RF interference caused by common-mode current on an audio cable?
  46. A signal reads 20 dB over S9. How does its power compare with an S9 signal?
  47. How much signal strength change does one S unit typically represent?
  48. What is the purpose of a corona ball on an HF mobile antenna?
  49. How does a higher sunspot number affect HF propagation?
  50. In a series LC circuit, what happens to impedance when inductive and capacitive reactance are equal?
  51. How does an inductor's reactance change as the frequency of the applied AC goes up?
  52. What is the term for the inverse of impedance?
  53. About how many dB represents a factor of two increase or decrease in power?
  54. How many watts does an 800-ohm load consume when it is supplied with 400 volts DC?
  55. What is the PEP produced by 200 volts peak-to-peak across a 50-ohm dummy load?
  56. Which AC value heats a resistor the same as a DC voltage of equal value?
  57. A sine wave has an RMS voltage of 120 volts. What is its peak-to-peak voltage?
  58. What percentage of power is lost when a circuit has a 1 dB loss?
  59. What is the total resistance of 10-, 20-, and 50-ohm resistors connected in parallel?
  60. A transformer has a 500-turn primary and a 1500-turn secondary. What is the output with 120 VAC applied?
  61. What is the capacitance of three 100-microfarad capacitors connected in series?
  62. For maximum life of a standard 12-volt lead-acid battery, what is the lowest recommended discharge voltage?
  63. About how much forward voltage does a silicon junction diode need before it conducts?
  64. Why should wire-wound resistors be avoided in RF circuits?
  65. What two operating points does a bipolar transistor use when it works as a switch?
  66. About what is the typical upper frequency limit for low-SWR use of a 50-ohm BNC connector?
  67. Which statement describes a type N RF connector?
  68. How does a ferrite bead reduce common-mode RF current on the shield of a coax cable?
  69. What does a power supply bleeder resistor do?
  70. Which rectifier circuit uses two diodes and a center-tapped transformer?
  71. Compared with a linear supply, which is a characteristic of a switchmode power supply?
  72. Which of these amplifier classes has the highest efficiency?
  73. How many different states can a 3-bit binary counter have?
  74. In software-defined radio, what is the phase difference between the I and Q signals?
  75. What is the frequency above which a low-pass filter's output power is less than half the input power?
  76. What type of modulation does the FT8 digital mode use?
  77. Which of these phone emissions uses the narrowest bandwidth?
  78. What is an effect of overmodulation?
  79. What is the total bandwidth of an FM phone signal with 5 kHz deviation and a 3 kHz modulating frequency?
  80. What combination of a mixer's local oscillator and RF input frequencies is found in the output?
  81. Which digital mode is used as a low-power beacon to assess HF propagation?
  82. What are the two frequencies of a frequency shift keyed signal called?
  83. Which type of code is used for sending characters in a PSK31 signal?
  84. What is the nominal characteristic impedance of window line transmission line?
  85. How does the attenuation of coaxial cable change as the frequency increases?
  86. In what units is RF feed line loss usually expressed?
  87. What SWR results from connecting a 50-ohm feed line to a 200-ohm resistive load?
  88. What best describes the radiation pattern of a quarter-wave ground-plane vertical antenna?
  89. About how long is a half-wave dipole antenna cut for 14.250 MHz?
  90. In a three-element Yagi, how do the reflector and director lengths compare with the driven element?
  91. For the same antenna, how does gain in dBi compare with gain in dBd?
  92. What is the primary use of a Beverage antenna?
  93. What is one way that RF energy can affect human body tissue?
  94. Which stations are subject to the FCC rules on RF exposure?
  95. If your station's RF energy exceeds permissible human exposure limits, what must you do?
  96. What size fuse or circuit breaker is appropriate for a circuit wired with AWG number 14?
  97. What condition makes a ground fault circuit interrupter (GFCI) disconnect AC power?
  98. What should you do before climbing a tower that supports electrically powered devices?
  99. What is the purpose of a power supply interlock?
  100. How far can one hop via the E region normally travel?