2016-E0A: Safety: amateur radio safety practices; RF radiation hazards; hazardous materials; grounding
What is the primary function of an external earth connection or ground rod?
Reduce received noise
Reduce RF current flow between pieces of equipment
Reduce RFI to telephones and home entertainment systems
When evaluating RF exposure levels from your station at a neighbor's home, what must you do?
Make sure signals from your station are less than the uncontrolled MPE limits
Make sure signals from your station are less than the controlled MPE limits
You need only evaluate exposure levels on your own property
Advise your neighbors of the results of your tests
Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?
Use an antenna modeling program to calculate field strength at accessible locations
Use a calibrated antenna analyzer
Use a hand calculator plus Smith-chart equations to calculate the fields
All of the choices are correct
When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?
Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
Only the most powerful transmitter
Only commercial transmitters
Each transmitter operating with a duty-cycle greater than 50 percent
What is one of the potential hazards of using microwaves in the amateur radio bands?
The high gain antennas commonly used can result in high exposure levels
Microwaves are ionizing radiation
Microwaves often travel long distances by ionospheric reflection
The extremely high frequency energy can damage the joints of antenna structures
Why are there separate electric (E) and magnetic (H) field MPE limits?
All of these choices are correct
The body reacts to electromagnetic radiation from both the E and H fields
Ground reflections and scattering make the field impedance vary with location
E field and H field radiation intensity peaks can occur at different locations
How may dangerous levels of carbon monoxide from an emergency generator be detected?
Only with a carbon monoxide detector
By the odor
Any ordinary smoke detector can be used
By the yellowish appearance of the gas
What does SAR measure?
The rate at which RF energy is absorbed by the body
Synthetic Aperture Ratio of the human body
Signal Amplification Rating
The rate of RF energy reflected from stationary terrain
Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?
What toxic material may be present in some electronic components such as high voltage capacitors and transformers?
Which of the following injuries can result from using high-power UHF or microwave transmitters?
Localized heating of the body from RF exposure in excess of the MPE limits
Hearing loss caused by high voltage corona discharge
Blood clotting from the intense magnetic field
Ingestion of ozone gas from the cooling system
● = Unseen
● = Weak
● = Review
● = Learned
● = Incorrect answer