Electrical and RF Safety Flashcards
7 cards from real Ham Radio General Class Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Electrical and RF Safety flashcards as text
What is the significance of the 'near field' region around an antenna for RF safety?
Answer: RF field strength in the near field can be very high and complex, making exposure harder to predict
In the near field, RF field patterns are complex and intensity can be extremely high, making it difficult to predict exposure using simple far-field calculations.
What action should be taken if a tower must be climbed while an antenna on the structure is still active?
Answer: The transmitter must be shut off and locked out before anyone climbs
The transmitter must be completely shut off and locked out/tagged out to prevent accidental transmission while someone is on the tower near the antenna.
Which factor does NOT reduce RF exposure to a bystander near your station?
Answer: Increasing the length of the coaxial feedline
Increasing feedline length does not meaningfully reduce RF exposure to a bystander; only power reduction, distance, and directional gain management do.
What is the purpose of a Ground Fault Circuit Interrupter (GFCI) in an amateur radio shack?
Answer: To protect against electric shock by tripping when current leaks to ground through a person
A GFCI detects even small current imbalances indicating current may be flowing through a person to ground, and trips the circuit before a lethal shock can occur.
Why is it important for amateurs to use only properly rated fuses and circuit breakers in their stations?
Answer: To limit available fault current and protect against fire and shock from overcurrent conditions
Properly rated overcurrent protection limits the amount of current in a fault, preventing wiring fires and reducing shock hazard from damaged equipment.
When evaluating RF exposure for an omnidirectional vertical antenna, what is typically used as the worst-case direction?
Answer: Directly to the side (azimuthal plane)
For an omnidirectional vertical, the maximum radiation is in the horizontal plane (broadside), so the worst-case exposure is evaluated at ground level in that direction.
What common household substance should always be kept away from RF power amplifiers and transmitters due to fire risk?
Answer: Flammable solvents, aerosols, and cleaning sprays
Flammable solvents and aerosols near high-power equipment can ignite from sparks, arcs, or hot surfaces, creating serious fire and burn hazards.