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Stuff Every Ham Radio Operator Should Know

Learn the FCC Technician question pool (2026 to 2030) one card at a time.

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โฑ Timed practice exam

FCC Element 2 (Technician) exam: 35 questions, no time limit, pass with 26 right (74%). (official format)

No time limit on the real exam.

Take it like the real thing: the real number of questions, no hints until you finish, then your score by topic, every miss explained, and a readiness score from your last 3 exams.

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About the real test: FCC amateur radio Technician exam (Element 2)

Rules change: always check the official source before test day.

Try 3 cards

  1. Which agency makes and enforces the rules for amateur radio in the United States?
    Show the answer

    The FCC. The Federal Communications Commission writes and enforces the ham radio rules, found in Part 97. The ARRL is a big ham club, not a government regulator.

  2. Which of these is prohibited for amateur radio operators?
    Show the answer

    Willful or malicious interference. Hams may never deliberately interfere with other stations. Talking to other countries on VHF and passing third-party messages by digital modes are both allowed under the right conditions.

  3. Where can a Technician use voice (phone) on the 10-meter band?
    Show the answer

    28.300 to 28.500 MHz. Technicians get a small voice segment on 10 meters, from 28.300 to 28.500 MHz. The lower part of their 10 meter privileges is for CW and data.

All 341 practice questions

The first 50 are free, with the answer, why it's right and the official sources. The other 291 (๐Ÿ”’) are for AhaBulb members. Or play them as a game and track what you've learned.

Show all 341 questions
  1. Which agency makes and enforces the rules for amateur radio in the United States?
  2. Which of these is prohibited for amateur radio operators?
  3. Where can a Technician use voice (phone) on the 10-meter band?
  4. Which frequency is inside the 6-meter amateur band?
  5. Which amateur band includes the frequency 146.52 MHz?
  6. On which HF band does a Technician have voice (phone) privileges?
  7. What is the maximum PEP output for a Technician in their HF band segments?
  8. Except for special cases, what is the max PEP output for Technicians above 30 MHz?
  9. For which amateur license classes does the FCC currently issue new licenses?
  10. Who may pick a call sign they want under the FCC vanity call sign rules?
  11. How long before it expires can you ask to renew your amateur radio license?
  12. What is the normal term of an FCC amateur radio license?
  13. What is the grace period for renewing an amateur license after it expires?
  14. After passing your first ham exam, when may you start transmitting?
  15. Which kind of one-way transmission is prohibited for amateur stations?
  16. What are the rules about indecent or obscene language on amateur radio?
  17. When may an amateur station transmit without a control operator?
  18. What determines the frequencies a ham station may transmit on?
  19. When must you transmit your assigned call sign?
  20. What language must you use for station identification on voice (phone)?
  21. What is a common repeater offset on the 2-meter band?
  22. What is the national FM simplex calling frequency on 2 meters?
  23. How should you answer a station calling CQ?
  24. What do hams call transmitting and receiving on the same frequency?
  25. What does the reverse function on a VHF/UHF radio let you do?
  26. What is the sub-audible tone sent with your voice to open a repeater's squelch called?
  27. What type of repeater signaling uses two audio tones at the same time?
  28. Which Q signal means you are changing frequency?
  29. What is RACES?
  30. What is standard practice when you take part in a radio net?
  31. Can a control operator ever transmit outside their license privileges?
  32. Why can VHF signal strength change a lot when you move your antenna a few feet?
  33. What does the ham radio term picket fencing mean?
  34. Which region of the atmosphere can reflect HF radio waves?
  35. As a radio wave's frequency increases, what happens to its wavelength?
  36. What is the formula for approximate wavelength in meters?
  37. What frequency range is called VHF?
  38. What propagation often causes occasional strong signals on 10, 6 and 2 meters from beyond the horizon?
  39. What causes tropospheric ducting?
  40. Why is the VHF and UHF radio horizon farther than the visual horizon?
  41. Why use short, heavy-gauge wires for a radio's DC power connection?
  42. Where should a mobile radio's negative power lead connect in a vehicle?
  43. What happens when microphone gain is set too high on SSB?
  44. In a US three-wire 120 V AC cable, what does black wire insulation mean?
  45. What is the minimum safe distance from a power line when installing an antenna?
  46. What type of radiation are radio signals?
  47. Who must make sure no one is exposed to RF energy above FCC limits?
  48. What hazard comes from touching an antenna while it is transmitting?
  49. Electrical current is measured in which unit?
  50. A difference in what causes electrons to flow in a circuit?
  51. What is the unit of frequency? ๐Ÿ”’
  52. Why are metals generally good conductors of electricity? ๐Ÿ”’
  53. Which of these is a good electrical insulator? ๐Ÿ”’
  54. How many milliamperes is 1.5 amperes? ๐Ÿ”’
  55. Going from 5 watts to 10 watts is closest to how many decibels? ๐Ÿ”’
  56. Which decibel value represents a power increase from 20 watts to 200 watts? ๐Ÿ”’
  57. How much power is delivered by 13.8 volts DC at 10 amperes? ๐Ÿ”’
  58. What is the resistance of a circuit where 3 amperes flows from 90 volts? ๐Ÿ”’
  59. In which type of circuit is the current always the same through all components? ๐Ÿ”’
  60. What type of component is often used as an adjustable volume control? ๐Ÿ”’
  61. What electrical component stores energy in an electric field? ๐Ÿ”’
  62. Which battery chemistry is NOT rechargeable? ๐Ÿ”’
  63. What electronic component allows current to flow in only one direction? ๐Ÿ”’
  64. How is the cathode lead of a diode often marked on the package? ๐Ÿ”’
  65. What are the names of the electrodes of a bipolar junction transistor? ๐Ÿ”’
  66. What is an electrical diagram using standard component symbols called? ๐Ÿ”’
  67. Which device changes alternating current into a varying direct current signal? ๐Ÿ”’
  68. What is a relay? ๐Ÿ”’
  69. What term describes a receiver's ability to discriminate between multiple signals? ๐Ÿ”’
  70. What device converts the RF input and output of a transceiver to another band? ๐Ÿ”’
  71. What can you do if you are told your FM radio is over-deviating? ๐Ÿ”’
  72. What is the primary purpose of a dummy load? ๐Ÿ”’
  73. What SWR reading indicates a perfect impedance match between antenna and feed line? ๐Ÿ”’
  74. What happens to power lost in a feed line? ๐Ÿ”’
  75. Which of the following causes failure of coaxial cables? ๐Ÿ”’
  76. How is a voltmeter connected to a component to measure applied voltage? ๐Ÿ”’
  77. Which type of solder should NOT be used for radio and electronic work? ๐Ÿ”’
  78. What is the characteristic appearance of a cold tin-lead solder joint? ๐Ÿ”’
  79. Which voice mode is often used for long-distance, weak signal contacts on VHF and UHF? ๐Ÿ”’
  80. Which type of modulation is commonly used for VHF and UHF voice repeaters? ๐Ÿ”’
  81. Which of these signal types has the narrowest bandwidth? ๐Ÿ”’
  82. Which sideband is normally used for 10-meter HF, VHF, and UHF single-sideband communications? ๐Ÿ”’
  83. What is the approximate bandwidth of a typical single sideband voice signal? ๐Ÿ”’
  84. What is the approximate bandwidth of an FM voice signal on VHF repeaters? ๐Ÿ”’
  85. What is Doppler shift in satellite communications? ๐Ÿ”’
  86. What does LEO mean for communication satellites? ๐Ÿ”’
  87. What is FT8? ๐Ÿ”’
  88. Which is an application of APRS? ๐Ÿ”’
  89. Which of the following describes DMR? ๐Ÿ”’
  90. How is the polarization of an antenna described? ๐Ÿ”’
  91. Which of the following increases the resonant frequency of a dipole antenna? ๐Ÿ”’
  92. Why is a 19-inch-long vertical antenna often used on 2 meters? ๐Ÿ”’
  93. In which direction does a half-wave dipole radiate the strongest signal? ๐Ÿ”’
  94. What is the most common impedance of coaxial cables used in amateur radio? ๐Ÿ”’
  95. What happens to coaxial cable loss as signal frequency is increased? ๐Ÿ”’
  96. Which connector type is most suitable for RF frequencies above 400 MHz? ๐Ÿ”’
  97. Which type of feed line has the lowest loss? ๐Ÿ”’
  98. What is a common repeater offset on the 70-centimeter band? ๐Ÿ”’
  99. What type of electrical component stores energy in a magnetic field? ๐Ÿ”’
  100. What is one purpose of the Amateur Radio Service? ๐Ÿ”’
  101. What proves the FCC has issued your amateur license grant? ๐Ÿ”’
  102. How does Part 97 define an amateur space station? ๐Ÿ”’
  103. Who recommends channels for repeater and auxiliary stations? ๐Ÿ”’
  104. Who selects an amateur Frequency Coordinator? ๐Ÿ”’
  105. Who may contact the ISS on amateur VHF frequencies? ๐Ÿ”’
  106. Which bands let Technicians use digital modes such as FT8? ๐Ÿ”’
  107. What must U.S. amateurs do in a secondary band segment? ๐Ÿ”’
  108. Why should you leave room inside an amateur band edge? ๐Ÿ”’
  109. What international messages may FCC-licensed amateur stations exchange? ๐Ÿ”’
  110. When may you use your amateur license in international waters? ๐Ÿ”’
  111. Which countries may FCC-licensed amateurs not contact? ๐Ÿ”’
  112. When may a ham message be encoded to hide its meaning? ๐Ÿ”’
  113. When may an amateur phone transmission include music? ๐Ÿ”’
  114. When may hams announce radio equipment for sale on air? ๐Ÿ”’
  115. Which link is an example of an amateur auxiliary station? ๐Ÿ”’
  116. When may a control operator be paid for operating? ๐Ÿ”’
  117. When may hams support broadcasting or news gathering? ๐Ÿ”’
  118. What does broadcasting mean in amateur radio rules? ๐Ÿ”’
  119. When may an amateur station transmit without on-air identification? ๐Ÿ”’
  120. What is required during an on-air test transmission? ๐Ÿ”’
  121. Who may control a station using an amateur satellite? ๐Ÿ”’
  122. Who must designate an amateur station's control operator? ๐Ÿ”’
  123. What is an amateur station's control point? ๐Ÿ”’
  124. May a Technician control a station in an Extra-only segment? ๐Ÿ”’
  125. Which station operation is an example of automatic control? ๐Ÿ”’
  126. Which amateur stations may be remotely controlled? ๐Ÿ”’
  127. Which activity is remote control under Part 97? ๐Ÿ”’
  128. When must a licensee allow FCC inspection of a station? ๐Ÿ”’
  129. Which identification rule applies to a station transmitting phone signals? ๐Ÿ”’
  130. Which spoken call sign separators are acceptable on phone? ๐Ÿ”’
  131. What special rule applies when an unlicensed person speaks to a foreign ham? ๐Ÿ”’
  132. What are third-party communications in amateur radio? ๐Ÿ”’
  133. Which station retransmits another ham signal on a different channel? ๐Ÿ”’
  134. Who is accountable when a repeater unknowingly relays a rule violation? ๐Ÿ”’
  135. What is required for a club station license grant? ๐Ÿ”’
  136. How should you seek any phone contact without a repeater? ๐Ÿ”’
  137. What does the procedural signal CQ mean? ๐Ÿ”’
  138. How do you announce that you want a repeater contact? ๐Ÿ”’
  139. What is an amateur band plan beyond FCC privileges? ๐Ÿ”’
  140. What is a linked repeater network? ๐Ÿ”’
  141. Two stations on the same frequency interfere with each other. What should happen? ๐Ÿ”’
  142. What is the color code on a DMR repeater system? ๐Ÿ”’
  143. What does the squelch function on a receiver do? ๐Ÿ”’
  144. In DMR digital radio, what is a talkgroup? ๐Ÿ”’
  145. How do you make sure unusual words in a voice message are received correctly? ๐Ÿ”’
  146. In a radio net, what does traffic mean? ๐Ÿ”’
  147. Which system relays messages using email addresses based on ham call signs? ๐Ÿ”’
  148. What is in the preamble of a formal traffic message? ๐Ÿ”’
  149. What does check mean in a radiogram header? ๐Ÿ”’
  150. Which emergency radio group requires certification by a civil defense agency? ๐Ÿ”’
  151. How do trees and plants affect UHF and microwave signals? ๐Ÿ”’
  152. On a line-of-sight VHF or UHF path, what does cross-polarization of the antennas do? ๐Ÿ”’
  153. Buildings block your path to a distant repeater. How might a directional antenna still reach it? ๐Ÿ”’
  154. What weather condition might decrease range at microwave frequencies? ๐Ÿ”’
  155. What is a likely cause of irregular fading of signals that travel by the ionosphere? ๐Ÿ”’
  156. Ionospheric signals are elliptically polarized. What does that mean for your antenna choice? ๐Ÿ”’
  157. What effect does fog or rain have on 10-meter and 6-meter band signals? ๐Ÿ”’
  158. How are the electric and magnetic fields of a radio wave related? ๐Ÿ”’
  159. What are the two components of a radio wave? ๐Ÿ”’
  160. How fast does a radio wave travel through free space? ๐Ÿ”’
  161. Besides frequency, what is used to identify amateur radio bands? ๐Ÿ”’
  162. What is one characteristic of VHF signals received by auroral backscatter? ๐Ÿ”’
  163. What effect may let radio signals travel beyond obstructions between two stations? ๐Ÿ”’
  164. Which band is best suited for communicating by meteor scatter? ๐Ÿ”’
  165. When is 10 meters usually best for long-distance F region propagation? ๐Ÿ”’
  166. At the peak of the sunspot cycle, which bands may give long-distance contacts via the F region? ๐Ÿ”’
  167. What should you consider when choosing an accessory SWR meter? ๐Ÿ”’
  168. In an FT8 station, how are the transceiver's audio input and output connected? ๐Ÿ”’
  169. What signals are used in a computer-radio interface for digital mode operation? ๐Ÿ”’
  170. Which is a required connection between a computer and a transceiver for digital modes? ๐Ÿ”’
  171. Which conductor is preferred for bonding station equipment at RF? ๐Ÿ”’
  172. What function does a digital mode hotspot perform for nearby transceivers? ๐Ÿ”’
  173. What is an electronic keyer? ๐Ÿ”’
  174. Which of these can you use to enter a transceiver's operating frequency? ๐Ÿ”’
  175. How should squelch be set so you can hear a weak FM signal? ๐Ÿ”’
  176. What does an FM signal sound like when received slightly off frequency? ๐Ÿ”’
  177. What does the scanning function of an FM transceiver do? ๐Ÿ”’
  178. An SSB voice answering your CQ sounds too high or too low in pitch. Which control can fix it? ๐Ÿ”’
  179. What is a DMR code plug? ๐Ÿ”’
  180. Why is a choice of receiver filter bandwidths useful in a multimode transceiver? ๐Ÿ”’
  181. How is a specific group of stations selected on a DMR digital voice transceiver? ๐Ÿ”’
  182. What must be programmed into a D-STAR digital transceiver before transmitting? ๐Ÿ”’
  183. Electrical power is measured in which units? ๐Ÿ”’
  184. What is the term for the flow of electrons in an electric circuit? ๐Ÿ”’
  185. What term describes the number of times per second that an alternating current makes a complete cycle? ๐Ÿ”’
  186. Which describes alternating current? ๐Ÿ”’
  187. Which term describes the rate at which electrical energy is used? ๐Ÿ”’
  188. Which types of current flow are opposed by resistance? ๐Ÿ”’
  189. Which is equal to 1,500,000 hertz? ๐Ÿ”’
  190. Which is equal to one kilovolt? ๐Ÿ”’
  191. Which is equal to 500 milliwatts? ๐Ÿ”’
  192. Which is equal to 3000 milliamperes? ๐Ÿ”’
  193. Which is equal to 3.525 MHz? ๐Ÿ”’
  194. Which is equal to 1,000,000 picofarads? ๐Ÿ”’
  195. Which is equal to 28400 kHz? ๐Ÿ”’
  196. What describes the ability to store energy in an electric field? ๐Ÿ”’
  197. What is the unit of capacitance? ๐Ÿ”’
  198. What is the unit of inductance? ๐Ÿ”’
  199. What is the unit of impedance? ๐Ÿ”’
  200. What is the abbreviation for kilohertz? ๐Ÿ”’
  201. What is the abbreviation for megahertz? ๐Ÿ”’
  202. What formula is used to calculate electrical power (P) in a DC circuit? ๐Ÿ”’
  203. How much power is delivered by a voltage of 12 volts DC and a current of 2.5 amperes? ๐Ÿ”’
  204. How much current is required to deliver 120 watts at a voltage of 12 volts DC? ๐Ÿ”’
  205. What is impedance? ๐Ÿ”’
  206. What formula is used to calculate current in a circuit? ๐Ÿ”’
  207. What formula is used to calculate voltage in a circuit? ๐Ÿ”’
  208. What is the resistance of a circuit for which the applied voltage is 12 volts and the current flow is 1.5 amperes? ๐Ÿ”’
  209. What is the resistance of a circuit that draws 4 amperes from a 12-volt source? ๐Ÿ”’
  210. What is the current in a circuit with an applied voltage of 120 volts and a resistance of 80 ohms? ๐Ÿ”’
  211. What is the current through a 100-ohm resistor connected across 200 volts? ๐Ÿ”’
  212. What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through it? ๐Ÿ”’
  213. In which type of circuit is the voltage always the same across all components? ๐Ÿ”’
  214. What electrical component opposes the flow of current in a DC circuit? ๐Ÿ”’
  215. What electrical parameter is controlled by a potentiometer? ๐Ÿ”’
  216. What type of electrical component consists of conductive surfaces separated by an insulator? ๐Ÿ”’
  217. What electrical component is typically constructed as a coil of wire? ๐Ÿ”’
  218. What is the function of an SPDT switch? ๐Ÿ”’
  219. Which switch type simply opens or closes one single circuit? ๐Ÿ”’
  220. Which choice lists all three rechargeable battery chemistries? ๐Ÿ”’
  221. Which is true about forward voltage drop in a diode? ๐Ÿ”’
  222. Which component can be used as an electronic switch? ๐Ÿ”’
  223. Which component can consist of three semiconductor regions? ๐Ÿ”’
  224. What type of transistor has a gate, drain, and source? ๐Ÿ”’
  225. What does the abbreviation FET stand for? ๐Ÿ”’
  226. What are the names for the electrodes of a diode? ๐Ÿ”’
  227. Which component can provide power gain? ๐Ÿ”’
  228. What does gain mean in an amplifier? ๐Ÿ”’
  229. Which schematic symbol is a zigzag line? ๐Ÿ”’
  230. Which part's schematic symbol is a circle with three leads and an arrow on one lead? ๐Ÿ”’
  231. Which part's schematic symbol looks like a small rounded bulb with a loop inside? ๐Ÿ”’
  232. Which component uses alternating long and short parallel lines? ๐Ÿ”’
  233. Which component uses a symbol with two separated plates? ๐Ÿ”’
  234. Which component uses a diode symbol with arrows pointing outward? ๐Ÿ”’
  235. Which component uses a resistor symbol with an adjustable contact? ๐Ÿ”’
  236. Which component uses two coupled coils in its schematic symbol? ๐Ÿ”’
  237. Which component uses a coil symbol with an adjustable tap? ๐Ÿ”’
  238. Which part's schematic symbol is a line topped by an upside-down triangle? ๐Ÿ”’
  239. What is a reason to use shielded wire? ๐Ÿ”’
  240. Which part displays an electrical quantity as a number? ๐Ÿ”’
  241. What type of circuit controls the amount of voltage from a power supply? ๐Ÿ”’
  242. What component changes 120 V AC power to a lower AC voltage? ๐Ÿ”’
  243. Which of these is commonly used as a visual indicator? ๐Ÿ”’
  244. What device combines several semiconductors and other components into one package? ๐Ÿ”’
  245. Which of these is a resonant or tuned circuit? ๐Ÿ”’
  246. What term describes a receiver's ability to detect the presence of a signal? ๐Ÿ”’
  247. What is used to convert a signal from one frequency to another? ๐Ÿ”’
  248. What is the name of a circuit that generates a signal at a specific frequency? ๐Ÿ”’
  249. What does a transceiver's PTT input do when it is grounded? ๐Ÿ”’
  250. What is combining speech with an RF carrier signal called? ๐Ÿ”’
  251. What can be added to a transceiver's output to increase transmitted power? ๐Ÿ”’
  252. What does the VFO circuit in a transceiver do? ๐Ÿ”’
  253. What receiver problem can make broadcast radio pick up an out-of-band ham signal? ๐Ÿ”’
  254. Can fundamental overload, harmonics and spurious emissions all cause radio frequency interference? ๐Ÿ”’
  255. What might cause low RF power output from a solid-state transceiver? ๐Ÿ”’
  256. What might reduce out-of-band overload in a neighbor's over-the-air radio or TV? ๐Ÿ”’
  257. A neighbor says your transmissions interfere with their TV. What should you do? ๐Ÿ”’
  258. What can reduce interference to a 2-meter radio from a nearby commercial FM station? ๐Ÿ”’
  259. Something in a neighbor's home causes harmful interference to your station. What should you do? ๐Ÿ”’
  260. What is the first step for cable TV (not fiber optic) interference from your ham transmissions? ๐Ÿ”’
  261. Your audio through an FM repeater is reported distorted. Which could be the problem? ๐Ÿ”’
  262. What can eliminate distorted voice transmissions caused by RF feeding back into the transmitter? ๐Ÿ”’
  263. What is used to check if an antenna is resonant at the desired operating frequency? ๐Ÿ”’
  264. Why do most solid-state transmitters reduce output power as SWR rises? ๐Ÿ”’
  265. Which instrument can be used to determine SWR? ๐Ÿ”’
  266. Which instrument would you use to measure electric potential? ๐Ÿ”’
  267. When measuring current, how is a multimeter connected to a component? ๐Ÿ”’
  268. How does an ohmmeter measure the resistance of a circuit or component? ๐Ÿ”’
  269. Which of these can damage a multimeter? ๐Ÿ”’
  270. Which pair of measurements is made using a basic multimeter? ๐Ÿ”’
  271. What reading shows an ohmmeter is across a large, discharged capacitor? ๐Ÿ”’
  272. What precaution should you take when measuring in-circuit resistance with an ohmmeter? ๐Ÿ”’
  273. What type of modulation is commonly used for VHF packet radio? ๐Ÿ”’
  274. What is one characteristic of single sideband (SSB) compared to FM? ๐Ÿ”’
  275. Which is a disadvantage of FM compared with single sideband? ๐Ÿ”’
  276. What telemetry information is typically transmitted by satellite beacons? ๐Ÿ”’
  277. What is the impact of using too much effective radiated power on a satellite uplink? ๐Ÿ”’
  278. What does a satellite tracking program provide? ๐Ÿ”’
  279. Which modes do amateur radio satellites commonly use? ๐Ÿ”’
  280. What is a satellite beacon? ๐Ÿ”’
  281. What information do you enter into a satellite tracking program? ๐Ÿ”’
  282. What does it mean if a satellite is operating in U/V mode? ๐Ÿ”’
  283. What causes spin fading of satellite signals? ๐Ÿ”’
  284. Who is permitted to receive telemetry from an amateur radio satellite? ๐Ÿ”’
  285. How can you tell your uplink power into a linear transponder satellite is about right? ๐Ÿ”’
  286. Which method helps locate a source of radio noise or jamming? ๐Ÿ”’
  287. What item is useful during a hidden transmitter hunt? ๐Ÿ”’
  288. What activity means contacting as many stations as possible in a set time? ๐Ÿ”’
  289. What is good practice when contacting another station in a contest? ๐Ÿ”’
  290. What is a grid locator in amateur radio? ๐Ÿ”’
  291. What is Voice Over Internet Protocol, or VoIP? ๐Ÿ”’
  292. What does the Internet Radio Linking Project connect? ๐Ÿ”’
  293. Which protocol can initiate a repeater transmission without using a radio? ๐Ÿ”’
  294. What must you do before using EchoLink? ๐Ÿ”’
  295. What is a station called when it connects other amateur stations to the internet? ๐Ÿ”’
  296. Which list contains only digital communication modes? ๐Ÿ”’
  297. Which group of information can APRS transmit? ๐Ÿ”’
  298. What kind of transmission does NTSC indicate? ๐Ÿ”’
  299. What does the abbreviation PSK mean? ๐Ÿ”’
  300. Which set of features is included in packet radio transmissions? ๐Ÿ”’
  301. What does CW refer to in amateur radio operating? ๐Ÿ”’
  302. Which activities can WSJT-X digital software support? ๐Ÿ”’
  303. What role does ARQ play in a transmission system? ๐Ÿ”’
  304. What best describes an amateur radio mesh network? ๐Ÿ”’
  305. What is one disadvantage of a short handheld antenna? ๐Ÿ”’
  306. Which listed antenna type offers the greatest gain? ๐Ÿ”’
  307. Why can a handheld VHF radio work poorly inside a vehicle? ๐Ÿ”’
  308. What does antenna gain mean? ๐Ÿ”’
  309. Why is coaxial cable the most common amateur radio feed line? ๐Ÿ”’
  310. What is the main function of an antenna tuner? ๐Ÿ”’
  311. Where are PL-259 coax connectors commonly used? ๐Ÿ”’
  312. Which group lists three sources of coaxial feed-line loss? ๐Ÿ”’
  313. What can cause erratic changes in SWR? ๐Ÿ”’
  314. How does RG-213 differ electrically from RG-58 coax? ๐Ÿ”’
  315. What does standing wave ratio measure? ๐Ÿ”’
  316. What hazard can come from shorting an unprotected 12-volt battery? ๐Ÿ”’
  317. Which effects can electrical current have on the body? ๐Ÿ”’
  318. What is the purpose of a fuse in a circuit? ๐Ÿ”’
  319. Why must a 5-amp fuse not be replaced with a 20-amp fuse? ๐Ÿ”’
  320. Which set lists good ways to guard against electrical shock? ๐Ÿ”’
  321. What precaution matters when measuring high voltage with a voltmeter? ๐Ÿ”’
  322. How should tower ground-wire connections be installed for lightning protection? ๐Ÿ”’
  323. Which requirements belong together for safe tower climbing? ๐Ÿ”’
  324. When is it safe to climb a tower without a helper or observer? ๐Ÿ”’
  325. What must you look for before putting up an antenna tower? ๐Ÿ”’
  326. Why put a safety wire through a guy-line turnbuckle? ๐Ÿ”’
  327. When may a crank-up tower be climbed? ๐Ÿ”’
  328. What is a proper grounding method for a tower? ๐Ÿ”’
  329. How should bends be handled in lightning grounding conductors? ๐Ÿ”’
  330. What establishes grounding requirements for an amateur tower or antenna? ๐Ÿ”’
  331. Which listed amateur band has the lowest maximum permissible RF exposure? ๐Ÿ”’
  332. What happens to allowable RF power density when duty cycle drops from 100 to 50 percent? ๐Ÿ”’
  333. Which methods can determine compliance with FCC RF exposure rules? ๐Ÿ”’
  334. Why does duty cycle matter when determining safe RF exposure? ๐Ÿ”’
  335. What is duty cycle during the RF exposure averaging time? ๐Ÿ”’
  336. Which is equal to 2425 MHz? ๐Ÿ”’
  337. What describes the ability to store energy in a magnetic field? ๐Ÿ”’
  338. What formula is used to calculate resistance in a circuit? ๐Ÿ”’
  339. What is the current through a 24-ohm resistor connected across 240 volts? ๐Ÿ”’
  340. What is the voltage across a 10-ohm resistor if a current of 1 ampere flows through it? ๐Ÿ”’
  341. What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it? ๐Ÿ”’