Study › Technician › T0C › T0C08

T0C08

SAFETY · RF hazards: radiation exposure, proximity to antennas, recognized safe power levels, radiation types, duty cycle

T0C08T0C →

Which of the following actions can reduce exposure to RF radiation?

  1. ARelocate antennas
  2. BRelocate the transmitter
  3. CIncrease the duty cycle
  4. DAll these choices are correct
Why RF exposure comes from the antenna, not the equipment box, so moving the antenna farther from people or living spaces is the most effective fix. Power density falls off with the square of the distance, so doubling the separation cuts exposure to one quarter. Other valid steps are reducing power, reducing duty cycle, or limiting transmit time, but of the choices listed only antenna relocation helps.
Watch out Moving the transmitter does nothing, because the RF energy is radiated from the antenna at the far end of the feedline, and raising the duty cycle actually increases average exposure because the transmitter is on for a larger fraction of the time.
Exposure comes from the antenna, not the radio. More distance, less power, lower duty cycle.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
← T0C07 All of T0C T0C09 →

The rest of T0C

  1. T0C01 What type of radiation are radio signals?
  2. T0C02 Which of the following bands has the lowest maximum permissible exposure for RF safety?
  3. T0C03 How does the allowable power density for RF safety change if duty cycle changes from 100 percent to 50 percen…
  4. T0C04 What factors affect the RF exposure of people near an amateur station antenna?
  5. T0C05 Why do exposure limits vary with frequency?
  6. T0C06 Which of the following is an acceptable method to determine whether your station complies with FCC RF exposur…
  7. T0C07 What hazard is created by touching an antenna during a transmission?
  8. T0C08 Which of the following actions can reduce exposure to RF radiation?
  9. T0C09 How can you make sure your station stays in compliance with RF safety regulations?
  10. T0C10 Why is duty cycle one of the factors used to determine safe RF radiation exposure levels?
  11. T0C11 What is the definition of duty cycle during the averaging time for RF exposure?
  12. T0C12 How does RF radiation differ from ionizing radiation (radioactivity)?
  13. T0C13 Who is responsible for ensuring that no person is exposed to RF energy above the FCC exposure limits?
Powerwerx SS-30DV 30A DC Power SupplySponsored · View on Amazon →Baofeng BF-F8HP Pro Dual Band HandheldSponsored · View on Amazon →