Ham Radio Technician Test Safety, Grounding & RF Exposure 2 — Questions and Answers
Question 1: Why is it dangerous to touch an antenna while transmitting?
- RF burns can occur because the antenna carries high-frequency voltage that can heat tissue (Correct answer)
- The antenna will become permanently detuned
- The transmitter will be damaged by reflected power
- The FCC prohibits touching antennas during transmission
Correct answer: RF burns can occur because the antenna carries high-frequency voltage that can heat tissue
Touching a transmitting antenna can cause RF burns because the high-frequency current on the antenna can heat body tissue rapidly at the contact point.
Question 2: What safety precaution should be taken before climbing a tower?
- Ensure the transmitter is off and tag the power switch to prevent accidental operation (Correct answer)
- File a climbing permit with the FCC
- Notify all stations on the local repeater
- Complete a full station log entry
Correct answer: Ensure the transmitter is off and tag the power switch to prevent accidental operation
Before climbing a tower, the transmitter must be turned off and the power switch tagged or locked out to prevent anyone from accidentally transmitting while you are near the antenna.
Question 3: What type of grounding is recommended to protect a station from lightning damage?
- A single-point ground with all equipment bonded together and connected to an earth ground rod (Correct answer)
- Multiple separate ground connections for each piece of equipment
- A ground connected only to the coax shield
- A plastic insulating mat under all equipment
Correct answer: A single-point ground with all equipment bonded together and connected to an earth ground rod
A single-point ground system bonds all equipment to a common bus and connects it to an earth ground rod, minimizing voltage differences during a lightning event.
Question 4: What is the minimum safe distance a power line should be from an amateur radio tower?
- Far enough that the tower and all attached hardware cannot fall onto the power line (Correct answer)
- At least 10 feet horizontally
- At least 50 feet vertically
- There is no specific requirement
Correct answer: Far enough that the tower and all attached hardware cannot fall onto the power line
The tower and everything attached to it must be positioned so that if it falls in any direction it cannot contact a power line, preventing deadly electrocution hazards.
Question 5: What is the purpose of a lightning arrestor on a coaxial feedline?
- To divert lightning-induced surges to ground before they reach the radio equipment (Correct answer)
- To improve the SWR of the antenna system
- To prevent RF leakage from the coax
- To boost received signal strength
Correct answer: To divert lightning-induced surges to ground before they reach the radio equipment
A coax lightning arrestor provides a low-impedance path to ground for lightning-induced voltage surges, protecting the radio equipment connected to the feedline.
Question 6: Which of the following is a symptom of RF in the shack (RF feedback)?
- Distorted transmitted audio, equipment acting erratically, or operator experiencing tingling sensations (Correct answer)
- Increased SWR on all bands
- Faster battery drain on handheld radios
- Reduced range on the 2-meter band only
Correct answer: Distorted transmitted audio, equipment acting erratically, or operator experiencing tingling sensations
RF feedback causes distorted audio, erratic equipment behavior, and can cause the operator to feel a tingling sensation from RF current flowing through the station.
Ham Radio Technician Test Safety, Grounding & RF Exposure 2
Why is it dangerous to touch an antenna while transmitting?