Topic G0B Quick Review Audio


Which wire or wires in a four-conductor connection should be attached to fuses or circuit breakers in a device operated from a 240 VAC single phase source?

  1. Only the two wires carrying voltage
  2. Only the neutral wire
  3. Only the ground wire
  4. All wires


According the National Electrical Code, what is the minimum wire size that may be used safely for wiring with a 20 ampere circuit breaker?

  1. AWG number 20
  2. AWG number 16
  3. AWG number 12
  4. AWG number 8


Which size of fuse or circuit breaker would be appropriate to use with a circuit that uses AWG number 14 wiring?

  1. 100 amperes
  2. 60 amperes
  3. 30 amperes
  4. 15 amperes


Which of the following is a primary reason for not placing a gasoline-fueled generator inside an occupied area?

  1. Danger of carbon monoxide poisoning
  2. Danger of engine over torque
  3. Lack of oxygen for adequate combustion
  4. Lack of nitrogen for adequate combustion


Which of the following conditions will cause a Ground Fault Circuit Interrupter (GFCI) to disconnect the 120 or 240 Volt AC line power to a device?

  1. Current flowing from one or more of the voltage-carrying wires to the neutral wire
  2. Current flowing from one or more of the voltage-carrying wires directly to ground
  3. Overvoltage on the voltage-carrying wires
  4. All these choices are correct


Which of the following is covered by the National Electrical Code?

  1. Acceptable bandwidth limits
  2. Acceptable modulation limits
  3. Electrical safety inside the ham shack
  4. RF exposure limits of the human body


Which of these choices should be observed when climbing a tower using a safety belt or harness?

  1. Never lean back and rely on the belt alone to support your weight
  2. Confirm that the belt is rated for the weight of the climber and that it is within its allowable service life
  3. Ensure that all heavy tools are securely fastened to the belt D-ring
  4. All these choices are correct


What should be done by any person preparing to climb a tower that supports electrically powered devices?

  1. Notify the electric company that a person will be working on the tower
  2. Make sure all circuits that supply power to the tower are locked out and tagged
  3. Unground the base of the tower
  4. All these choices are correct


Which of the following is true of an emergency generator installation?

  1. The generator should be located in a well-ventilated area
  2. The generator must be insulated from ground
  3. Fuel should be stored near the generator for rapid refueling in case of an emergency
  4. All these choices are correct


Which of the following is a danger from lead-tin solder?

  1. Lead can contaminate food if hands are not washed carefully after handling the solder
  2. High voltages can cause lead-tin solder to disintegrate suddenly
  3. Tin in the solder can "cold flow," causing shorts in the circuit
  4. RF energy can convert the lead into a poisonous gas


Which of the following is good practice for lightning protection grounds?

  1. They must be bonded to all buried water and gas lines
  2. Bends in ground wires must be made as close as possible to a right angle
  3. Lightning grounds must be connected to all ungrounded wiring
  4. They must be bonded together with all other grounds


What is the purpose of a power supply interlock?

  1. To prevent unauthorized changes to the circuit that would void the manufacturer's warranty
  2. To shut down the unit if it becomes too hot
  3. To ensure that dangerous voltages are removed if the cabinet is opened
  4. To shut off the power supply if too much voltage is produced


What must you do when powering your house from an emergency generator?

  1. Disconnect the incoming utility power feed
  2. Insure that the generator is not grounded
  3. Insure that all lightning grounds are disconnected
  4. All these choices are correct


What precaution should you take whenever you adjust or repair an antenna?

  1. Ensure that you and the antenna structure are grounded
  2. Turn off the transmitter and disconnect the feed line
  3. Wear a radiation badge
  4. All these choices are correct